This PDF file contains the front matter associated with SPIE Proceedings Volume 10520, including the Title Page, Copyright information, Table of Contents, and Conference Committee listing.

SiC is highly anticipated as the material to be used in the next generation of power devices. However, due to its high rigidity, it is difficult to process, has a low throughput in the wafer production process, and has a high cost. In order to solve these issues, we have developed the KABRA process – a new wafer-production process which uses laser processing technology – and have devised fully-automatic equipment called “KABRA!zen,” which enables the mass production of SiC wafers. KABRA!zen achieves approximately twice the throughput and one-third the material loss of the conventional processes.

Stealth Dicing(SD) method is superior to blade dicing as well as other laser dicing methods such as laser ablation in terms of debris free and fully dry process. Therefore, SD is used to solve various problems in the dicing process, contributing to development of advanced devices and cost reduction. In this paper, we introduced a improved SD engine(SDE) that solves the problem that thick wafers, which have been pointed out as weak points of SD, require many laser scanning. The laser with the wavelength in the short wavelength infrared(SWIR) region was used and the spherical aberration that occurred when internal focusing of silicon was corrected by using LCoS-SLM. As a result, the crack propagation from the SD layer was significantly enhanced, achieving 3.5 times the throughput of the conventional SDE in a silicon wafer with 300 μm thickness.

Laser ablation has emerged as a novel method to synthesize various nanomaterials.1-3 Currently, most works merely focus on the material synthesis using laser ablation technique with little attention to the relationship between the ablated substrates and the synthesized materials. This work is aimed at filling this gap and giving new insights based on laser ablation of single crystal diamond-cubic (dc) (400) Si in air. Polycrystallization is a ubiquitous phenomenon occurring during laser ablation of Si. The polycrystallization rate of the ablated areas increases with increasing the laser powers, which well explains the polycrystalline instinct of the synthesized nanomaterials. Faster cooling rates of the laser-generated molten Si layers over their nucleation rates result in the surface amorphoization. The molten layers together with the newly formed polycrystalline Si materials will be pushed upward in air by shockwaves to solidify into the amorphous SiOx encapsulated polycrystalline Si composites. Reference: 1. Zhang, D.; Gökce, B.; Barcikowski, S. Laser Synthesis and Processing of Colloids: Fundamentals and Applications. Chem. Rev. 2017, 117, 3990. 2. Zhang, D.; Liu, J.; Li, P.; Tian, z.; Liang, C. Recent Advances in Surfactant-Free, Surface Charged and Defect-Rich Catalysts Developed by Laser Ablation and Processing in Liquids. ChemNanoMat 2017, DOI:10.1002/cnma.201700079. 3. Zhang, D.; Liu, J.; Liang, C. Perspective on how laser-ablated particles grow in liquids. Sci. China Phys. Mech. Astron. 2017, 60, 074201.

Cu-based fine patterns were directly fabricated using femtosecond laser reduction of Cu₂O nanospheres (NSs) via nonlinear optical absorption. Cu₂O NS solution films, containing Cu₂O NSs, polyvinylpyrrolidone (PVP), and 2-propanol, were prepared by spin-coating of the Cu₂O NS solution on glass substrates or Cu-coated glass substrates. Finer line patterns were formed by scanning the focused femtosecond laser pulses. The absorption of the Cu₂O NS solution film at wavelength of the femtosecond laser pulses, 780 nm, was low, whereas the intense absorption at wavelength of 390 nm was observed. Finer patterns were obtained on the Cu-coated glass substrates than on the glass substrates. The minimum line width of 0.6 μm was obtained on the Cu-sputtered film, which was smaller than the focal spot diameter of 1.3 μm. The heat accumulation is lower on the Cu-sputtered films due to their high thermal conductivity, resulting that the line width with the sub diffraction limit was achieved. The electrical conductivity of the patterns on the glass substrates was evaluated to be 4.1×10⁶ S/m at scanning speed of 200 μm/s and pulse energy of 0.312 nJ, which is close to that of bulk copper.

Three-dimensional (3D) microfluidic structures provide new opportunities for developing novel functional lab-on-a-chip devices. In the past decade, the femtosecond laser direct writing has been developed to become a unique and powerful technology for straightforward fabrication of 3D microfluidic structures in glass. Herein we overview our efforts on femtosecond laser fabrication of three-dimensional microfluidic structures in glass and their lab-on-a-chip applications such as the creation of high-complexity of microfluidic devices and functionalization of microchannels.

Aerospace and working tool industries are in a high demand of high resistant functional parts which can provide safety and sustainability at reasonable cost. Laser technology delivers hereby a well-defined portfolio of instruments which are already delivered and certified in these markets. High throughput can be achieved by high power long pulse radiation, whereby hybrid processing is of further advantage to raise the total yield of the process. By contrast, high quality products can be achieved by application of UV and/or short pulsed laser radiation. However, the latter occurs at the price of relatively low throughput. Structuring of industrial parts with high material removal rates with low material impact is, therefore, not that evident. The Laser MicroJet®, being the proprietary technology of Synova S.A., is already applied in the numerous applications serving markets such as diamond, working tools, aerospace, energy, watches, medical and semiconductor industries. The technology is centred on the coupling of laser light into a hair-thin laminar flow water jet, typically in the order of 25 to 120 microns in diameter. During cutting or grooving applications, the laser is used to ablate and melt the workpiece whilst the water-jet serves the purposes of cleaning, cooling and guiding. Low heat affected zone, absence of the heat accumulation and high throughput are characteristic features of the process. Until now, material removal rates (MRR) up to 13 mm3/min in Inconel and 2 mm3/min in PCBN have been reported. These materials are of high interest for aerospace and working tools manufacturing, respectively. Application of a new 400 W green laser together with the Laser MicroJet® has provided a tool to improve the MRR while retaining the low impact on the material. Inconel structuring has been progressed by increasing the MRR up to 30 mm3/min. In the paper we report both the new system and application results providing a turnkey instrument package for the addressed industries.

We report on an experimental study of the incubation effect during irradiation of stainless steel targets with bursts of femtosecond laser pulses at 1030 nm wavelength and 100 kHz repetition rate. The bursts were generated by splitting the pristine 650-fs laser pulses using an array of birefringent crystals which provided time separations between sub-pulses in the range from 1.5 ps to 24 ps. We measured the threshold fluence in Burst Mode, finding that it strongly depends on the bursts features. The comparison with Normal Pulse Mode revealed that the existing models introduced to explain the incubation effect during irradiation with trains of undivided pulses has to be adapted to describe incubation during Burst Mode processing. In fact, those models assume that the threshold fluence has a unique value for each number of impinging pulses in NPM, while in case of BM we observed different values of threshold fluence for fixed amount of sub-pulses but different pulse splitting. Therefore, the incubation factor coefficient depends on the burst features. It was found that incubation effect is higher in BM than NPM and that it increases with the number of sub-pulses and for shorter time delays within the burst. Two-Temperature-Model simulations in case of single pulses and bursts of up to 4 sub-pulses were performed to understand the experimental results.

The fabrication of a retinal implant capable to restoring vision to the blind requires access to the right materials and processes. In the past few years, carbon materials, in particular diamond and graphene, have proved to be of exceptional value in the creation of devices which can stimulate and record from neural tissue, including the retina. However, the properties that make these materials so attractive, such as chemcial stability, also make them hard to process. Laser processing offers the ideal solution to this problem. In this talk I will outline how we use lasers to create mutlielectrode diamond feedthrough arrays, and how lasers can be used to create a hermetic seal which encapsulates the electronics and protects the device from degradation due to exposure to the body for the lifetime of the patient. I will summarize by explaining how all these processes and materials are combined in a new generation of retinal implant: the diamond eye

Superimposed multiple shots of low-fluence femtosecond (fs) laser pulses form a periodic nanostructure on various kinds of solid surfaces through ablation. It has been proposed that the periodicity of the nanostructures is attributed to the excitation of surface plasmon polaritons (SPPs). However, the excitation of SPPs on non-metallic material surfaces was never been directly observed. We have observed anomalies appearing in the reflection of intense fs laser pulses at a Si grating surface with a grating structure. The results have exhibited an abrupt decrease to create a sharp dip at a specific incident angle, where the Si grating surface was deeply ablated along the edge of the grooves periodically. The experimental results and model calculation provide directly evidence that SPPs can resonantly be excited at the interface between air and the non-metallic material surface and that enhanced near fields can form periodic structures on the surface.

Stealth Dicing (SD) technology is an innovative laser dicing method, developed by Hamamatsu Photonics K. K., for semiconductor silicon wafers. In the advanced dicing process, a pulsed laser beam in the near-infrared region focused in a transparent wafer generates local modification regions, which become origins of cracks for separation. Owing to the non-contact and internal process, SD process has many advantages such as a completely dry process, high throughput, high quality, less kerf losses, and low running costs. The phenomenon of advanced dicing technology has not been sufficiently elucidated, and therefore many SD parameters have not been optimized although there are affect to dicing results. In this study, the laser modification phenomenon of SD in a Si wafer was investigated to focus on the actual phenomena. Firstly, the cleaved cross-section observation and nondestructive observation before cleaving has been conducted. Secondly, the subsurface time-resolved measurement have been proposed to observe SD mechanisms. Finally, in-situ observation of SD laser processing inside a Si wafer has been conducted to discuss the laser energy absorption phenomena. In addition, a few distinctive phenomena, including fine void structure with dislocation mapping, dynamics of transient absorption phenomenon inside the Si wafer after laser irradiation, and nanosecond-scale spreading of the laser shutoff phenomenon at SD laser focusing point, are confirmed.

We present a way to utilize 3D polymeric microstructures, fabricated by direct laser writing in pre-polymers, for smart materials’ applications. The structures undergo swelling or shrinkage induced by interaction with liquids which can be converted into different types of deformations (elongation, bending, etc.) by careful choice of the 3D geometry. Several architectural designs of the polymeric structures are proposed for sensing and actuation applications. A non-uniform sensitivity of an object to the surrounding medium is achieved by tweaking the geometry of the structures. Also, a novel design of the chemical sensor based on 3D periodic lattice produced Moiré pattern imaging is presented.

Femtosecond laser direct writing (FsLDW) is an emerging technology enabling arbitrary patterning via non-contact and maskless fabrication processes. The femtosecond pulse irradiation converts the graphene oxide (GO) into reduced graphene oxide (rGO) by removing the oxygen-containing groups of the GO, which is called photoreduction process. Because of its high printing resolution, sub-micron 2D optical structures can be printed based on GO and rGO as the base material. This study describes the fabrication of ultrathin GO/rGO optical components, which can be coated on arbitrary substrates. In the photoreduction using FsLDW, the resultant rGO’s optical properties such as refractive index, absorption coefficient, and surface reflectivity are varied on the input laser parameters, such as light wavelength, intensity, pulse repetition rate, and scan speed. To investigate the effects in detail, we performed parametric studies with different average intensity, pulse energy, and repetition rates at two wavelengths (343 nm and 515 nm). By adjusting the parameters, we could control the optical performances of the printed 2D optical structures. In addition, we studied the morphology changes of the rGO surfaces dependent on the laser parameters. The morphology plays an important role in transferring the rGO layer into the flexible polymer substrate. We will show the critical parameters for the morphology and propose the best conditions for the effective transfer of printed rGO patterns into the various flexible substrate.

We report on the dynamics of the excitation process of dielectrics using a spatial Bessel beam intensity distribution with pulse durations below 10 ps. The generated free-electron plasma is analyzed by time-resolved transversal pump-probe shadowgraphy on a timescale up to 20 ps after initial excitation. Our measurements reveal the ultrafast generation of the free-electron plasma, which reaches a maximum after approximately 10 ps. The subsequent relaxation is comparable slow with a time constant in the range of 100 ps. We perform measurements with different pump pulse durations in the range from 0.1 ps up to 9 ps and observe that the spatial distribution of the generated free-electron plasma strongly depends on the pulse duration and pulse energy. Our results show that the spatial distribution of the free-electron plasma can be controlled by a coarse adjustment of the pulse parameters. The understanding of the correlation of the spatial energy deposition and pulse parameters is useful for a high precision and fast glass cutting process.

The mass production of micro-elements in scientific research and industry, such as micro-electronic devices, bio-compatible micro-devices and micro-optical elements, has necessitated the development of high-efficiency laser processing techniques. High-throughput laser material processing demands precise control of the laser beam position to achieve optimal efficiency, but existing methods can be both time-consuming and cost-prohibitive. In the paper, we demonstrate a new high-throughput material processing technique based on rapidly scanning the laser focal point along the optical axis using an acoustically-driven variable focal length lens. Our results show that this scanning method enables higher processing rates over a range of defocus distances in various materials including metals, semiconductors, polymers and glass. In a specific example of silicon, we achieve a nearly threefold increase in the machining rate while maintaining sharp side walls and a small spot size. This method holds great potential for improving material processing efficiency in traditional systems, and also opens the door to applying laser processing to pieces with uneven topography that have traditionally been difficult to process.

Functionalization of surfaces equips products and components with new features like hydrophilic behavior, adjustable gloss level, light management properties, etc. Small feature sizes demand diffraction-limited spots and adapted fluence for different materials. Through the availability of high power fast repeating ultrashort pulsed lasers and efficient optical processing heads delivering diffraction-limited small spot size of around 10μm it is feasible to achieve fluences higher than an adequate patterning requires. Hence, parallel processing is becoming of interest to increase the throughput and allow mass production of micro machined surfaces.

The first step on the roadmap of parallel processing for cylinder embossing dies was realized with an eight- spot processing head based on ns-fiber laser with passive optical beam splitting, individual spot switching by acousto optical modulation and an advanced imaging. Patterning of cylindrical embossing dies shows a high efficiency of nearby 80%, diffraction-limited and equally spaced spots with pitches down to 25μm achieved by a compression using cascaded prism arrays. Due to the nanoseconds laser pulses the ablation shows the typical surrounding material deposition of a hot process.

In the next step the processing head was adapted to a picosecond-laser source and the 500W fiber laser was replaced by an ultrashort pulsed laser with 300W, 12ps and a repetition frequency of up to 6MHz. This paper presents details about the processing head design and the analysis of ablation rates and patterns on steel, copper and brass dies. Furthermore, it gives an outlook on scaling the parallel processing head from eight to 16 individually switched beamlets to increase processing throughput and optimized utilization of the available ultrashort pulsed laser energy.

Roll-to-roll UV nanoimprint lithography (R2R-UV-NIL) gains increasing industrial interest for large-area nano- and microstructuring of flexible substrates. It combines the possibility of multi length scale and 2.5D patterning of a functional resist with a square meter per minute productivity. The fabrication of micro- and nanooptic elements and systems nowadays can be named a classical application of batch NIL. However, large-area application fields like display, photovoltaics or solar cell markets ask for upscaling possibilities with respect to active area and throughput. The combination of direct laser lithography, step+repeat imprinting for shim fabrication and R2R reproduction even offers a much higher diversity of application fields. Free form lenses and mirrors, waveguiding units or complex light manipulating systems add new possibilities for customized photonic systems, security features or large area high-end decoration. Within this talk we will present the possibilities of combining greyscale laser lithography and roller-based imprinting with functionalized high-k imprint resins and see how to produce meters-per-minute 2.5D optical features on flexible substrates.

Direct Laser Interference Structuring (DLIP) is a manufacturing technology capable to functionalize large areas with high-precision periodic patterns. However, for industrial use of this emerging technology, solutions must be developed for specific requirements. With the objective of optimizing Direct Laser Interference Patterning in terms of process speed, an advanced optical module was developed that permits to superimpose two laser beams obtaining the interference pattern within an elongated area (linear spot) to meet the requirements of high-speed processing. After that, the influence of the process parameters on the quality of the surface patterns produced with the developed optical assembly was determined. It could be shown that the pulse overlap, in contrast to the applied average fluence, has a significant influence on the resulting structure heights of the produced patterns. Furthermore, it became apparent that during the course of the process, the underlying physical process dynamics seem to change, which was indicated by the resulting structure heights variations over the process. The gained findings will make a contribution to improving the quality of surface patterns produced with DLIP and to enabling reliable manufacturing qualities in the future.

We present a systematic study on the generation of 2D surface structures on stainless steel, using double, crosspolarized femtosecond pulses with variable interpulse delay. We demonstrate the combined effect of the interpulse delay and key process parameters in order to obtain periodic structures. The sets of double pulses were produced utilizing a modified Michelson interferometer with interpulse delay varying from -100 ps to +2 ns. The study was carried out with an industrial laser having pulse duration of 350 fs, emitting in the near infrared (λ = 1030 nm), operating at 100 kHz coupled with a Galvo scanner. We evaluate the obtained surface morphology and structure period using SEM characterization and Fourier analysis.

We show the effects of double pulse processing with a pico-second laser for internal modification of transparent materials. In recent years, the need for laser processing of transparent materials has been growing. Many applications for such laser processing exist, such as the formation of through-silicon via, scribing glass and creating optical wave guides. Creation of photonic devices and circuits are also expected. A large amount of applied research on the processing of transparent materials has been conducted, but many of the processing mechanisms remain unexplained. In general, fluence thresholds are related to free-electron density caused by multi-photon ionization and avalanche ionization. Additionally, the internal fluence threshold of transparent materials is lower than surface fluence thresholds. We applied the double pulse method to the internal modification of transparent materials, and investigated how the second pulse affects the generation of microcracks. We used a pico-second laser with a 532-nm wavelength for the first pulse and a 1064-nm wavelength for the second pulse. The target was fused silica glass. In this paper, we show our experimental results and discuss the processing mechanism of the double pulse method. We call it the double pulse explosion drilling method. Moreover, we discover a processing method that can be applied to the high-rate drilling and scribing of transparent materials.

Ultrafast laser direct writing is a fascinating technology which emerged more than two decades from fundamental studies of material resistance to high-intensity optical fields. Its development saw the discovery of many puzzling phenomena and demonstration of useful applications. Today, ultrafast laser writing is seen as a technology with great potential and is rapidly entering the industrial environment. Whereas, less than 10 years ago, ultrafast lasers were still confined within the research labs. This talk will overview some of the unique features of ultrafast lasers and give examples of its applications in optical data storage, polarization control and optical fibers.

Laser Direct Write techniques for printing applications of living material is currently a hot topic in different biomedical and engineering fields like tissue engineering, drug delivery, biosensing, etc. specialized groups in the field have been done to find and control the ideal conditions of printability, in order to maintaining unchanged the properties of the biological transferred material. In this work we present a comprehensive study of the printability map of two of the most used biocompatible hydrogels, Sodium Alginate and Methylcellulose. We discuss the effect of hydrogel density, laser parameters influence, etc. using a blister assisted laser writing technique. In our approach we use a thick polyamide layer for blister generation, this presents huge advantages to limit the direct laser irradiation of the living material to be transferred. In addition the physics of blister dynamics and droplet-jet formation is discussed by means of a combined study using numerical modeling of the process fluid dynamics and high speed imaging of the transfer. Finally a particular example of advantages of the approach from the biological point of view is discussed presenting a cell viability study of Jurkat cell printing in the conditions discussed in the study

Micropatterns consisting of reduced graphene oxide (rGO) and graphene oxide (GO) were fabricated via laser direct writing where an insulating GO was converted to a conductive rGO by laser-induced reduction. The rGO/GO microinterdigitated electrode showed humidity sensing behaviors. The influence of the shape and size of the rGO/GO microinterdigitated electrode was studied to discuss the sensing mechanism and to improve the sensitivity. Three kinds of rGO(w)/GO(g) micropatterns were prepared by laser direct writing on a GO-coated PET (polyethylene terephthalate) substrate using a CW 405 nm semiconductor laser, where w and g are the rGO electrode width and the GO gap width between rGO electrodes in micrometer unit, respectively. The humidity sensing properties of rGO(400)/GO(100), rGO(160)/GO(40), and rGO(80)/GO(20) were studied by monitoring the output voltage waveform from an electronic circuit consisting an rGO/GO interdigitated electrode and resistors in AC mode operation. The sensitivity enhancement induced by charging property of an rGO/GO interdigitated electrodes was observed accompanying transient decay of the output voltage. The shape and size of an rGO/GO interdigitated electrode remarkably influenced the humidity sensing behaviors depending on the contribution ratio of C and R parameters.

This paper discusses latest results obtained in high-pulse repetition frequency micro hole percussion drilling of metal foils ranging between 25 μm and 100 μm thickness. In the investigations a high-repetition frequency, high average power ultrashort pulse laser source was applied, providing a near-infrared laser beam of 1.03 μm wavelength, 87.5 W maximum average laser power (at the processing plane), 51.48 MHz maximum pulse repetition frequency, 650 fs pulse duration, and 30 μm focal spot size. In the experiments, the process parameters pulse energy, pulse repetition frequency, and the pulse number were varied thus in order to evaluate their influence on both micro hole geometry (hole diameter, roundness), and drilling quality (thermal modification, melting residues). The minimum pulse number required to drill through the metal foils was detected by an in-house developed pulse counter. A significant lower pulse number to drill through the material was observed when irradiating ultrashort pulses of megahertz pulse repetition rates. On the one hand, this effect might be induced by thermal accumulation thus increasing the substrate temperature which, in turn, enhances the laser beam absorption or rather lowers the energy consumption needed for evaporation. On the other hand, pulse interactions with the still existing plasma at these very short pulse intervals cannot be neglected, so a higher amount of material might be ejected assisted by the higher plasma pressure. As another detrimental effect for megahertz pulses, a significantly lower processing quality was obtained that was due to intensive melting affected by heat accumulation, as the melt re-solidified within and/or surrounding the drilling holes. Surprisingly, by irradiating pulses at 20 MHz and above, the melt was completely ejected out from the drilling holes as the drilling efficiency was even the highest. Finally, based on the findings of this study, optimum parameter settings are presented with regard to highest machining quality and drilling throughput.

This study presents the comparison of laser drilling of nickel based superalloy in air and vacuum environment. A 300W Nd:YAG laser was used to carry out the experimental study, pulse width and pulse peak power were studied of their influence on the hole quality and appearance, the experiments were respectively conducted in air and vacuum. It was found that the holes drilled in vacuum were much different to those drilled in air. Laser of shorter pulse width may drill the better holes in the air, but in the vacuum it was the pulse width around 1ms that produced holes of the best quality.

Shape memory alloys (SMAs) are a unique class of smart materials and they were employed in various applications in engineering, biomedical, and aerospace technologies. Here, we report an advanced, efficient, and low-cost direct imprinting method with low environmental impact to create thermally controllable surface patterns. Patterned microindents were generated on Ni₅₀Ti₅₀ (at. %) SMAs using an Nd:YAG laser with 1064 nm wavelength at 10 Hz. Laser pulses at selected fluences were focused on the NiTi surface and generated pressure pulses of up to a few GPa. Optical microscope images showed that surface patterns with tailorable sizes can be obtained. The depth of the patterns increases with laser power and irradiation time. Upon heating, the depth profile of SMA surfaces changed where the maximum depth recovery ratio of 30 % was observed. Recovery ratio decreased and saturated at about 15 % when the amount of time and thus the indent depth was increased. Laser-induced shock wave propagation inside the material was simulated and showed a good agreement with the experimental results. The stress wave closely followed the rise time of the laser pulse to its peak value and initial decay. Rapid attenuation and dispersion of the stress wave were observed.

Coronary stents are manufactured through a sequence of processes and each step demands the process control to assure surface quality. This study is focused on the influence of laser cutting parameters and electropolishing on average surface roughness and back wall dross percentage for fiber laser cutting of AISI 316L coronary struts. A preliminary test and a design of experiments (DOE) were implemented to determine the limiting cutting conditions and the effect of these parameters on quality indicators. Preliminary results identify four cutting zones from a non-cut zone to a burned zone, in a frequency range between 1000 and 1500 Hz and a peak power between 160 to 180 W for clean cuts. From the DOE results, several interactions between factors were observed; however, a laser frequency of 1000 to 1500 Hz and a cutting speed of 250 mm/min minimize the backwall dross percentage and the surface roughness to values less than 2% and 0.9 μm, respectively. After the laser conditions selection, coronary stents were manufactured and electropolished to reduce the surface roughness on the strut edge. Electropolishing results indicate a surface roughness reduction from 0.9 μm to 0.3 μm after 300 s of electropolishing time.

Femtosecond lasers have been proved to be an effective fabrication tool to process with high machining quality and negligible thermal effects a wide variety of materials. However, the system technology enabling fast and precise scanning on the workpiece, currently limits the average power of these laser sources to less than 10 Watts of average power in most industrial application. To overcome this limitation, a proportional up-scaling of both, the laser repetition rate and scan speed is needed, demanding for faster scanning technologies. Recently, rugged, femtosecond lasers delivering pulses with repetition rates of several MHz and pulse energy up to some hundreds of μJ have been introduced to the market. In parallel, the development and commercialization of novel galvanometric scanner heads, enabling scan speeds well above 10 m/s is ongoing. Here we explored the capabilities of a novel set-up consisting of an industrial femtosecond laser delivering 100 W with a repetition rate up to 13 MHz coupled with an innovative galvanometric scanner head enabling scan speeds up to 30 m·s^-1. On stainless steel, we carried out engraving tests with both single line grooving and multiple surface raster scanning. By systematic variation of repetition rate and pules overlap we investigate how the machining quality and the ablation rate depend on the average laser power at different fluence levels. Heat accumulation effects are evaluated via Scanning Electron Microscope. Finally, we show how to scale-up the cutting of a 500 μm thick stainless-steel part varying the scan speed from 1 m·s^-1 to 20 m·s^-1.

A photonic nanojet is a highly concentrated laser beam observed in the vicinity of dielectric micro-objects such as glass micro-spheres. Thanks to the concentration of the beam beyond the diffraction limit, giving a spot with a width smaller than a half-wavelength, the incident power density can be multiplied by a factor larger than 200. Photonic jet obtained with microspheres has been applied successfully to material ablation. It has been demonstrated that the ablation on metal or glass can have a half-wavelength width using a common infrared nanosecond pulse laser. However, the spheres in contact with the sample are difficult to move to achieve an industrial process and are disturbed by the removed material at the beginning of the process. Recently we have shown that photonic nanojet obtained in the vicinity of shaped optical fiber tip is an alternative to overcome these limitations. Sub-micron etchings have been obtained on metals, semiconductors and ITO using multimode optical fibers with a numerically designed shaped tip. The possibility to perform not only ablation, but also to generate self-organized micro-peaks, has also been experimentally demonstrated. Besides the small size of the processed area, our talk will focus on the low energy required for material removal. Due to the high energy concentration, the required energy to ablate is already 20 times smaller than in a classical process. Finally, we will show how the energy coupling in the fiber is a parameter as important as the tip shape to decrease the energy required to reach ablation.

Novel glazing with embedded micro-mirrors can significantly reduce the energy consumption due to cooling and lighting in buildings. Especially promising are large arrays of periodic micro compound-parabolic-concentrators (CPCs) with angular-selected transmittance. For the production of micro CPCs, curved sidewall grooves with a controlled optical surface and an aspect ratio of about 2.3 are fabricated on polycarbonate substrates by scanning nanosecond 248-nm excimer laser ablation. The likewise obtained microstructures can be used as master mold for replication. The cross-sections of the micro grooves are characterized by confocal microscopy, and the extracted morphologies are used for the ray-tracing simulation of the optical devices. Prior to the scanning ablation using a suitable mask in the optical path, the depth profiles under static ablation are investigated to identify ablation rate, imaging resolution and produced surface. Interestingly for the width of the mask opening being less than 6 μm, the ablation rate is increased due to optical interference and /or less shielding by debris. Concerning the scanning ablation, the depth of the curved sidewall grooves ranges from 48 μm to 114 μm, corresponding to the width of the groove opening being in the range from 20 μm to 50 μm. The observed final shapes in cross-sections are in good agreement with the design of the mask. For both theoretical and fabricated groove shapes, the angular-selected transmittance profiles predicted from ray-tracing simulations are highly similar. Scanning nanosecond excimer laser ablation is therefore a promising approach for the realization of high-quality micro CPCs.

Ablation by ultrafast lasers results from a series of complex nonlinear phenomena of absorption and transfer of energy that take place in the surfaces of materials upon irradiation. Provided that a good window of processing parameters is chosen, the resulting thermal effects are in general negligible, making ultrafast lasers excellent micromachining tools applicable to most types of materials. It is thus beneficial to understand how ablation is affected by the laser processing parameters and the material properties, in order to optimize the micromachining processes.

We propose an engineering model to estimate the dimensions of ablation, taking into account on the one hand the material properties such as the ablation threshold, penetration depth and the refractive index and, on the other hand, the processing parameters namely the pulse energy and beam diameter, scanning speed, repetition rate and angle of incidence. The model considers as well the effects of incubation, changes of topography during multi-pulse irradiation, surface reflectivity and Gaussian beam diameter variation with the distance to the focal plane.

The model is able to simulate the profiles of ablation surfaces produced by normal or tilted laser beam, either for spot, line and area processing. The results obtained are validated by comparison to the ones obtained experimentally. Both the model and the experiments focus on stainless steel. The predictions of the model also allow for the optimization of the micromachining process, both energy and time wise.

2D and 3D metal microstructures are directly written using femtosecond laser reductive sintering of metal oxide nanoparticles. CuO nanoparticle solutions including CuO nanoparticles, a reductant agent, and a dispersant, were coated on glass substrates. Then, focused femtosecond laser pulses were irradiated onto the solution film to write the microstructures in air. Finally, non-irradiated CuO nanoparticles were removed. Cu-rich and Cu₂O-rich microstructures were selectively fabricated by controlling the laser irradiation conditions. We demonstrated direct-writing of 2D and 3D Cu-based microstructures using femtosecond laser-induced reduction of CuO NPs. Using respective appropriate femtosecond laser conditions, 3D Cu-rich microstructures were obtained by a combined process of the dispensing coating and laser irradiation. The Cu-rich hot-film flow sensor which had microbridge structure, were successfully produced. This direct-writing technique is useful for fabricating various sensors on arbitral shaped substrates in air.

Bioresorbable electronic devices are currently fabricated by complex and expensive vacuum-based Integrated Circuits (IC) processes. In this paper, we report a low-cost manufacturing approach for bioresorbable conductors on bioresorbable polymer substrates by evaporation-condensation-mediated laser printing and sintering of Zn nanoparticle. Laser sintering of Zn nanoparticles has been technically difficult due to the readily formation of surface oxide. We report a novel way to print and sinter Zn nanoparticle on low temperature substrate facilitated by evaporation-condensation in confined domain. This new approach circumvents the surface oxide, which notoriously hinders the nanoscale sintering process. The entire metallization process can be realized in non-vacuum environment allowing easy integration on a roll-to-roll production platform for economical manufacturing of bioresorbable electronics.

The main goal is to develop an optimized three-dimensional (3D) cell design with improved electrochemical properties, which can be correlated to a characteristic lithium distribution along 3D micro-structures at different State-of-Health (SoH). 3D elemental mapping was applied for characterizing the whole electrode as function of SoH. It was demonstrated that fs-laser generated 3D architectures improves the battery performance regarding battery power and lifetime. It was quantitatively shown by laser-induced breakdown spectroscopy that 3D architectures act as attractor for lithium-ions. Furthermore, lateral intrinsic porosity variations were identified to be possible starting points for lithium plating and subsequent cell degradation. Results achieved from post-mortem studies of cells with laser structured electrodes (intrinsic and artificial porosity variation), and unstructured lithium-nickel-manganese-cobalt-oxide electrodes will be presented.

Laser Micro-Spot Welding (LMSW) of metal sheets is a process widely used in medical, automotive and aerospace industries. This paper shows a process parameter selection for LMSW with AISI 302 stainless sheets, 254 μm in thickness. Experimental tests considered laser power, exposure time and focal distance parameters. The experimental setup produces the laser focal point over the part surface with a focal distance of 13.00 mm. The best results were obtained with an unfocused beam at a focal distance of 16.00 mm. Under the experimental conditions of this research, successful joining of AISI 302 thin sheets through LMSW is achieved with a combination of 175 W of average laser power and 0.25 s of exposure time (or a combination of 125 W and 1.00 s.). The width of the heat-affected zone (HAZ) was found to be 8% larger than the spot weld width, in average.

The high intensity laser power beaming (HILPB) system is one of the most promising systems in the long-rang wireless power transfer field. The vertical multi-junction photovoltaic (VMJ PV) array converts the HILPB into electricity to power the load or charges a battery. The output power of a VMJ PV array depends mainly on irradiance values of each VMJ PV cells. For simulating an entire VMJ PV array, the irradiance profile of the Gaussian HILPB and the irradiance level of the VMJ PV cell are mathematically modeled first. The VMJ PV array is modeled as a network with dimension m*n, where m represents the number of VMJ PV cells in a column, and n represents the number of VMJ PV cells in a row. In order to validate the results obtained in modeling and simulation, a laboratory setup was developed using 55 VMJ PV array. By using the output power model of VMJ PV array, we can establish an optimal power transmission path by the receiver based on the received signal strength. When the laser beam from multiple transmitters aimed at a VMJ PV array at the same time, the received power is the sum of all energy at a VMJ PV array. The transmitter sends its power characteristics as optically coded laser pulses and powers as HILPB. Using the attenuated power model and output power model of VMJ PV array, the receiver can estimate the maximum receivable powers from the transmitters and select optimal transmitters.

Glass waveguides are fabricated using laser processing techniques that have low optical loss with >90% optical throughput. Advanced light pipes are demonstrated, including angled facets for turning mirrors used for lens-to-light pipe coupling, tapers that increase the concentration, and couplers for combining the outputs from multiple lens array elements. Because they are fabricated from glass, these light pipes can support large optical concentrations and propagate broadband solar over long distances with minimal loss and degradation compared to polymer waveguides. Applications include waveguiding solar concentrators using multi-junction PV cells, solar thermal applications and remoting solar energy, such as for daylighting. Ray trace simulations are used to estimate the surface smoothness required to achieve low loss. Optical measurements for fabricated light pipes are reported for use in waveguiding solar concentrator architectures.

R2R (Roll-to-roll) production is a powerful process for patterning owing to its cost effectiveness and high productivity. Nanopatterned cylindrical molds for continuous fabrication of nanopatterned polymer film have been generally fabricated by various methods such as e-beam lithography, anodic oxidation, photolithography, or wrapping of nanopatterned sheets. However, these fabrication processes exhibit problems such as high economic and time costs, and creation of seam and stitch. In this paper, to overcome these problems, we suggest the cost-effective laser interference lithography (LIL) for fabrication of a nanopatterned cylindrical molds. LIL is a suitable process for fabricating high-resolution periodic nanometer patterns in large areas without the creation of seams or stitches. Periodic line patterns with hundred-nanometer periodicity were fabricated by LIL and pattern distortions were observed. Period and width of the line patterns on the cylindrical mold were measured along the circumference to experimentally confirm the distortion as related to the projection of light. Further, it was observed that the degree of distortion was dependent on the diameter of the cylindrical mold and the position along the circumference. However, it was theoretically expected that this distortion can be minimized below 0.2% by using a cylindrical mold with a sufficiently large diameter and control of the exposure area.

In recent years, numerous applications emerged on the market with seemingly contradicting demands. On one side, the structure size decreased while on the other side, the overall sample size and speed of operation increased. Although the principle usage of piezoelectric positioning solutions has become a standard in the field of micro- and nanopositioning, surface inspection and manipulation, piezosystem jena now enhanced the performance beyond simple control loop tuning and actuator design.

In automated manufacturing machines, a given signal has to be tracked fast and precise. However, control systems naturally decrease the ability to follow this signal in real time. piezosystem jena developed a new signal feed forward system bypassing the PID control. This way, we could reduce signal tracking errors by a factor of three compared to a conventionally optimized PID control.

Of course, PID-values still have to be adjusted to specific conditions, e.g. changing additional mass, to optimize the performance. This can now be done with a new automatic tuning tool designed to analyze the current setup, find the best fitting configuration, and also gather and display theoretical as well as experimental performance data. Thus, the control quality of a mechanical setup can be improved within a few minutes without the need of external calibration equipment. Furthermore, new mechanical optimization techniques that focus not only on the positioning device, but also take the whole setup into account, prevent parasitic motion down to a few nanometers.

With fast development of interdisciplinary fields relying on various micro- and nano-structures (for instance, microfluidics, micromechanics or biomedicine) the pressure is on for the fabrication technologies to meet the ever increasing demands for the manufacturing throughput and applicable materials. Glass is one of the key substances used through the ages for creation of various objects, yet till this day the possibilities to process it in micro-scale in 3D fashion is limited. Here, we provide examples of structures that can be created out of glass by applying fs laser assisted selective etching. These include molds for micromechanical part creation, high-quality microchannels and microneedle arrays. The possibilities, limitations and perspectives of this microfabrication technology are discussed, comparisons with additive manufacturing are provided.

Luminescence measurements of upconverting nanocrystals (UCNCs) dispersed in SZ2080 hybrid prepolymer being processed under different laser polymerization regimes are presented. Er³⁺ ions doped β-NaYbF4 UCNCs were prepared by a one-step thermal decomposition method. The ratio of the 2H_11/2 → 4I_15/2 and 4S_3/2→ 4I_15/2 emission intensities under λ= 980 nm excitation in the range from 24 to 70°C confirmed to follow Boltzmann type distribution and enabled a self-referenced optical readout of the sample temperature changes. Variation of thermally-coupled spectral bands intensity ratio was observed under typical laser writing conditions (1030 nm, 300 fs, 200 kHz, NA = 0.8) and E(pulse) varying from below threshold to the optical breakdown. Average fitted temperature changes around polymerized voxel calculated to be ΔT1<3 K within polymerization window and increases up to ΔT2 ≈ 170 K in overexposing regime.

We have successfully observed self-assembled periodic nanostructures inside Si single crystal and GaP crystal, by the femtosecond double-pulse irradiation. These results experimentally indicate that the self-assembly of the periodic nanostructures inside semiconductors triggered by ultrashort pulses irradiation are possibly associated with a direct or an indirect band gap. More recently we have also empirically classified the photoinduced bulk nanogratings into the following three types: (1) structural deficiency, (2) compressed structure, (3) partial crystallization. We have still a big question about what material properties are involved in the bulk nanograting structure formation. In this study, to expand the selectivity of the material for bulk nanograting formation, we have employed β-Ga₂O₃ crystals (indirect bandgap Eg ~ 4.8 eV) as a sample for femtosecond laser irradiation. The nanograting structure inside β-Ga₂O₃ crystal was aligned perpendicular to the laser polarization direction. Such phenomenon is similar to the nanograting in SiO₂ glass (Eg ~ 9 eV). Moreover, to clarify the band structure, we have also investigate the photoinduced structure in Sn doped β-Ga₂O₃ crystals, which exhibit direct bandgap according to the first principle calculation.

Large area, high speed, nanopatterning of surfaces by laser ablation is challenging due to the required high accuracy of the optical and mechanical systems fulfilling the precision of nanopatterning process. Utilization of self-organization approaches can provide an alternative decoupling spot precision and field of machining. The laser-induced front side etching (LIFE) and laser-induced back side dry etching (LIBDE) of fused silica were studied using single and double flash nanosecond laser pulses with a wavelength of 532 nm where the time delay ∆τ of the double flash laser pulses was adjusted from ∼50 ns to ∼10 μs. The fused silica can be etched at both processes assisted by a 10 nm chromium layer where the etching depth ∆z at single flash laser pulses is linear to the laser fluence and independent on the number of laser pulses, from 2 to 12 J/cm², it is ∆z = δ_LIFE/LIBDE ⋅ Φ with δ_LIFE ∼ 16 nm/(J/cm²) and δ_LIBDE ∼ 5.2 nm/(J/cm²) ∼ 3 ⋅ δ_LIFE. At double flash laser pulses, the ∆z is dependent on the time delay ∆τ of the laser pulses and the ∆z slightly increased at decreasing ∆τ. Furthermore, the surface nanostructuring of fused silica using IPSM-LIFE (LIFE using in-situ pre-structured metal layer) method with a single double flash laser pulse was tested. The first pulse of the double flash results in a melting of the metal layer. The surface tension of the liquid metal layer tends in a droplet formation process and dewetting process, respectively. If the liquid phase life time ∆t_LF is smaller than the droplet formation time the metal can be "frozen" in an intermediated state like metal bare structures. The second laser treatment results in a evaporation of the metal and in a partial evaporation and melting of the fused silica surface, where the resultant structures in the fused silica surface are dependent on the lateral geometry of the pre-structured metal layer. A successful IPSM-LIFE structuring could be achieved assisted by a 20 nm molybdenum layer at ∆τ ≥ 174 ns. That path the way for the high speed ultra-fast nanostructuring of dielectric surfaces by self-organizing processes. The different surface structures were analyzed by scanning electron microscopy (SEM) and white light interferometry (WLI).

Superhydrophobic surface has been widely studied on its theories and applications. Oil/water separation as one of its various applications shows great potential and attracts attention of researchers. In this paper, a round copper piece was used to fabricate an oil/water separation mesh by pulsed laser ablation and one-step simple chemical treatment. Based on the mechanism of hydrophobicity/lipophilicity, the fabricated copper mesh shows tunable excellent oil/water separation ability. Field emission scanning electron microscope (FESEM) was taken to study the surface morphology. Energy dispersive X-ray detector (EDX) shows the changes in surface chemical elements. Furthermore, by immersing in aqueous solutions with different PH values and the mechanical abrasion testing, the mesh still exhibits good superhydrophobicity, showing excellent stability in both harsh chemical environments and physical conditions. The fabrication approach can be flexibly scaled up to large-scale production, which has great potential applications in solving the problems of oil pollution.

This study was performed using picosecond pulses to obtain the three-dimensional micro-nano-hierarchical porous structures on the surface of titanium via the combination of the ablation and the deposition of ablated particles. For the repetition rate of 100 kHz and the scanning speed of 10 mm/s, there were secondary nano-tree-like micro-nano structures via the deposition of the ablated material formed on the primary microstructures. However, when the scan speed decreased, the primary microstructures were invisible owing to too much material deposition. When the repetition rate increased to 500 kHz, the ablated particles were irradiated by the posterior pulse before deposition onto the surface of material, and agglomerated into spidernet-like nanostructures. Then, the upper layer of the secondary micro-nano structure was molten and came into micro-nano porous fractal structures. Both the secondary micro-nano porous structures showed the hierarchy in the vertical and horizontal direction of the surface of titanium. Contact angle measurement after 3 months indicated that the nano-tree-like micro-nano structures showed super-hydrophilcity, and the spidernet-like nano and micro-nano porous fractal structures showed super-hydrophobicity.

Recently, there is an increasing interest to create micro-channels on metal thin films for diverse applications, such as biomedical, micro channel heat exchangers, chemical separation processes and microwave antenna. Nanosecond (ns) Nd³⁺:YAG laser has been studied for generating micro-channels on Cu thin film (35 μm) deposited on polyimide substrate (50 μm). A pulsed Nd³⁺:YAG laser (532 nm / 355 nm) based scribing was performed in air and water ambiancePlasma shielding phenomenon is observed to influence the depth of microchannel at higher energies. A novel pump-probe experiment has been conducted for verifying the plasma shielding effect in air. In underwater scribing the recast layer was reduced significantly as compared to that in air. Laser scribing of Cu thin film followed by chemical etching using FeCl₃ was studied. However, the approach of chemical etching resulted in undercut and thinning of Cu film. Alternatively, laser material processing in NaCl solution was studied. Cl⁻ ions present in the solution reacts with Cu which is removed from the sample via laser ablation and forms CuCl₂. Formation of CuCl2 in turn improved the surface morphology of the channel through localized etching. The surface roughness parameter Ra was less than 400 nm for NaCl solution based scribing which is smaller compared to air and underwater based methods which are typically around 800 nm or above. Preliminary studies using femtosecond (fs) laser based Cu scribing in air with the fluence of 0.5 J/cm² resulted in a crated depth of 3 μm without any recast layer.

Forces acting on thermally generated microbubbles are studied by deriving a general force model. Microbubbles can be steered by moving the laser beam. In previous work, it has been shown that the attractive thermo-capillary force on the microbubble is much larger than the repulsive optical force. Thus the microbubble is attracted toward the laser beam, which has been also observed experimentally. In this work, dynamics of a microbubble is studied by steering microbubbles with a known constant velocity. Thermocapillary force on the microbubble is calculated using a developed model which is based on the experimental velocity values and compared with the thermo-capillary force values obtained from the theory. The effect of the viscous and friction forces are also considered. Microbubbles are generated in a thin container as in our previous work and the container is placed on a motorized translation stage. After the bubble is generated and trapped by the focused laser beam the translational stage is moved with a known velocity until the microbubble is separated from the beam. Then the two thermo-capillary forces are compared as a function of the microbubble (translation stage) velocity.

Current fused silica surface processing, aimed at reducing known absorbing precursor concentration, has brought laboratory-tested ultraviolet laser-induced damage rates to nearly nil at fluences up to 10 J/cm² . Yet this damage rate reduction has not been fully realized in large facility operation. A recently discovered source of damage in the facility is from particles ejected from damage of a neighboring optic under laser exposure and deposited onto the substrate surface. This state was observed to provide a means to couple energy from a subsequent laser pulse into the contaminated substrate and cause damage characterized by fracture. In this work, we explore the rate at which particles are removed from the surface and the rate at which particles lead to damage as a function of laser fluence and particle characteristics. This analysis allows for a derivation of an optimal pre-exposure fluence of a contaminated optic which maximizes particle removal probability while minimizing surface damage probability. For fluences up to 9.5 J/cm² (351 nm, 5 ns square pulse), both particle removal and damage probabilities generally increased with particle size and laser fluence, with damage threshold around 6.5 J/cm^{2 .} Two possible mechanisms that facilitate particle-induced damage on the substrate surface from laser-generated and deposited ejecta will be discussed, namely i) enhanced thermal contact from molten or partially molten ejecta and ii) fracture generated upon impact of solid ejecta with high kinetic energy.

This paper presents results of poly(L-lactide) and poly(L-lactide)/hydroxyapatite composite cutting optimization using 2^nd harmonic of femtosecond fiber laser. There are several limitations regarding the use of femtosecond lasers for processing of heat-sensitive medical grade polymers such as poly(L-lactide) (PLLA). Improper use of ultrashort pulse laser may lead to heat load into surrounding material causing its melting and crack formation when excessive energy is deposited and pulse repetition frequency is too high. The optimization of laser parameters is necessary not only because of heat but also due to reflection and scattering of incident light in high aspect ratio V-shaped groove resulting in decrease of ablation rate with an increasing number of repetitions. This problem is especially important in case of polymer foils thicker than 200 μm and the beam spot size which is typically around 15 - 30 μm in commercial systems. In this work we present threshold fluence and ablation rates for three types of material: amorphous PLLA, crystalline PLLA and PLLA/hydroxyapatite composite. For those materials in form of thick foils (∼400 μm) we performed cutting optimization. A significant improvement of cutting efficiency in case of thick foils was made by applying a method of multiple, overlapped cuts.

In this paper, for the first time, we present an analysis of changes of physicochemical properties of poly(L-lactide) induced by the femtosecond laser. Introduced changes were characterized using Differential Scanning Calorimetry, Gel Permeation Chromatography, X-ray Photoelectron Spectroscopy and Fourier Transform Infrared spectroscopy. We have noted that even for these process parameters for which no thermal ablation effects occurred, we observed some changes in material properties. In GPC image we recorded an increase in polydispersity index and some reduction of the molecular weight. The FTIR spectra show a reduction in the number of both C=O and C−O−C bonds in the polymer as well as the appearance of new bands. By using the XPS it was determined that processing with femtosecond laser cause a small oxidation of the surface layer. Decay of the spectra indicates the possibility of carboxyl (−COOH) and hydroxyl (−OH) groups present in the modified polymer. Although the observed changes are relatively small compared to long pulse duration lasers or UV lasers, they cannot be neglected in biopolymer applications for tissue engineering.

The effect of the laser and the optomechanical parameters in the micromachining process of the complex geometry is the challenging part in the manufacturing industry due to wide range of materials. There are limited ways to find the best process parameters for machining and texturing with specific depth, thickness and roughness. The COMSOL software was used to model all the laser parameters like laser power, sampling rate, and optomechanical parameters like pulse overlap. Presented simulation demonstrates the roughness, depth and thickness of machined path. In addition, from the simulation point of view, the laser and optomechanical parameters can be optimized for the specific depth and thickness. To validate the numerical model, experiments are conducted for different process parameters by changing the laser power, varying the sampling rate of the laser and data acquisition card, changing the pulse overlap and the results are tabulated. Also the same input parameters are given to numerical simulation and the results are in good agreement with experimental outcomes. In conclusion, the simulated model can be used to estimate the effect of the process parameters before the machining. So that the presented model has the control over the machined surface quality and the process can be optimized by giving different material properties in the simulation.

Laser micro machining is one of the micro manufacturing processes. Since it has wide range of applications in Microelectronics, medical device, aerospace etc., the accuracy of the process is the most significant factor. In this study, the challenges and corresponding possible solutions that are encountered in machining complex geometries are addressed. Furthermore, the effect of process parameters on the overall quality of the manufacturing are discussed. The paper proposes mathematical function based and image processing based algorithms to find the machining coordinates. The former calculates the first and second derivatives of the functions to find the essential coordinates and the latter converts pixels of the image into coordinates. Achieving required overlap is one of the difficulty in the curved shapes, which can be solved by using both the algorithms. However, the function-based approach is more efficient as the image processing approach depends on the image resolution. Lower resolution results in reduction in smoothness of the extracted coordinates and higher resolution leads to increased computational cost. By changing the different laser parameters such as laser power and mechanical parameters like sampling rate of data acquisition card; different roughness, depth and overlaps can be attained. The study demonstrates precision micromachining and it establishes optimal relation between the process parameters and quality of the machined surface.