Arnoud Everhardt, Vasileios Konstantinidis, Paul Kapteijn, Marcel Hoekman, Soultana Konstantinidou, Marta D'Amora, Alessandro De Carli, Francesco Fuso, Francesco Tantussi, Michele Lai, Vittoria Raffa, Sadoon Al-Obaidi, Noor Schilder, René Heideman, Douwe Geuzebroek, Frederik Schreuder
Genome editing comprises the most promising work in 21st century genetics, with molecular surgery as its practical horizon. For a successful clinical application of molecular surgery, e.g. to treat cancer, safe and efficient editing is crucial. Light-induced molecular surgery is the perfect tool for its excellent control over wavelength, power, and exposure time. Light is also an excellent tool for the detection of (living) cells. These modalities are ideal for opto-fluidics: combining integrated photonics and microfluidics in a chip. In this work, we used the TriPleX® waveguide platform, comprised of silicon nitride and silicon oxide, to control high power (>1W) visible light. Living cells are inserted into a 100 micrometer wide microfluidic channel after which they are focused into a 25 micrometer wide section in its center using side-, backand lift sheath flows. The cells can be readily recovered at the microfluidic channel’s output with >90% survival rate. Chemically deactivated CRISPR/Cas9 molecules are activated by the laser light for safe molecular surgery. In parallel, it is possible to detect living cells flowing in the microfluidic channel. Measuring light absorption by the analyte makes it possible to detect each individual cell passing by the laser light, and to microscopically verify that >97% of the cells are correctly centered in the microfluidic channel. This device represents a first step to a fully integrated on-chip flow cytometer. Early results demonstrate its efficacy in cell detection and controllable exposure, paving the way to safe molecular surgery.
Single photon counting detectors are extremely important in the evolution of quantum technologies. The existing devices for the low-flux measurements are bulky and their implementation cannot be made with small footprints. Integrated photonics aims to allow the miniaturization of these setups. We present simulation results for the design of a single 1x10 multimode interference coupler (MMI) in terms of the power imbalance between the output waveguides, optical losses, and tolerance on the operating wavelength. This component acts as the fundamental building block of a photonic integrated circuit (PIC) in the TriPleX platform, acting as an optical divider that is able to bring down the power to ratio levels of 1:10-5. The central operating wavelength is 850 nm. This PIC is based on five cascaded 1x10 multimode interference couples (MMIs) in a novel function for bringing the power to an exceptionally low, and consistent level with repeatable and reproducible results. The fabricated photonic chips have been characterized in lab settings. The two best-performed PICs have been packaged and incorporated in a laboratory setup with embedded reference standards for optical power measurement in a technique referred to as "self-calibration". They were tested in system settings, where they successfully demonstrated that we have achieved a linear splitting ratio of 1:10-9 by cascading nine splitters.
A laser engine is demonstrated based on a silicon-nitride PIC. It uses a flip-chip assembly process for hybrid integration of the red, green and blue laser diodes, into etched recesses in the silicon nitride PIC and is based on passive alignment, meaning the laser is not tuned on during assembly. The TriPleX® waveguide technology optimizes the ellipticity of the modes at the laser side from 1:3 to circular (1:1) at the output side. Output powers of >1mW are measured and depend on the laser diodes used. The described assembly approach facilitates wafer level laser diode integration and wafer level hermetic packaging for scalable volume manufacturing.
We demonstrate a silicon-nitride Photonic Integrated Circuit based RGB light engine. The engine uses a flip chip laser diode assembly process for hybrid integration of the Red, Green and Blue laser diodes, as well as power monitoring detectors. The lasers are flip chip soldered in etched recesses in the silicon nitride PIC for optimal coupling. Small formfactor 5x10x1 mm3 (width x length x thickness) devices have been realized. Output powers of ~1mW are measured and depend on the laser diodes used. Typical coupling losses are 1.5 dB for the actively aligned implementations. The described assembly approach facilitates wafer level laser diode integration and wafer level hermetic packaging for scalable volume manufacturing.
We present a novel hybrid 800 nm laser with a wide tuning range, high optical power and ultra-narrow linewidth with ⪆kHz tuning speeds and a small footprint. Tunable, narrow linewidth hybrid lasers around 800nm serve as an attractive choice for e.g. OCT, LIDAR and atomic transition locking in e.g. atomic clocks. The laser has a microring resonator based optical cavity. The laser has a tuning range of 45 nm and a maximum output power of 5 dBm. The intrinsic linewidth of the laser is measured at 22 kHz.
We present ultra-low power stress optic actuators for high-speed switching in photonic integrated circuits using the standard silicon nitride TriPleX™ platform. The stress-optic actuator is created by a piezoelectric layer (lead zirconate titanate, PZT) on top of a Si3N4-based TriPleX™ waveguide in our standard Asymmetric Double Stripe (ADS) cross section. The top cladding thickness in between the actuator and the waveguide is chosen to achieve minimal optical loss (≤0.01dB/cm). The electrodes are placed on the top of- and directly below the PZT layer allowing the generation of a vertical electric field across the layer. This electrical field deforms the PZT layer by means of the piezoelectric effect. As a consequence of the PZT deformation stress is induced in the underlying waveguide. In this way, the refractive index of the waveguide is controlled by the stress-optic effect brought about by actuating the PZT layer. To demonstrate the stress-optic based phase actuation experimentally, a Mach-Zehnder Interferometer (MZI) is employed. The MZI is designed for operation at a wavelength of 1550 nm. We measure a half-wave voltage-length product (Vπ·cm) of 16 V·cm, while the half-wave-voltage length loss product (Vπ ·L·α) is 1.6 V·dB only. The 2π phase shift would be at 42 V. The measured response time is 4.25 μs. The quasi-DC power dissipation is able to go down to 1 μW. Compared with conventional thermo-optic actuators these characteristics show a dramatic improvement, being a factor of 50 faster in terms of switching speed and a factor of 100 000 lower in terms of quasi-DC power dissipation. This makes stress-optic actuators an attractive choice for the next generation integrated photonic circuits where ultra-low quasi-DC power dissipation and/or fast switching time and operation in the MHz range are required.
This paper presents a summary review of some of the available foundry services offering Silicon Photonics, comparing the key technologies available to European technology innovators that drive the technology sector. The foundries providing these unique technologies include AMF, CEA Leti, CORNERSTONE, Global Foundries, ihp, imec, and LioniX International. The review will also show examples of Silicon Photonics in emerging application domains from selected foundries.
Hybrid integration of semiconductor optical amplifiers with frequency-selective feedback circuits, implemented using low-loss Si3N4 waveguides, enables robust chip-sized lasers with outstanding properties. Deploying ring resonators as a tunable feedback filter provides single-mode operation over a wide wavelength range. Moreover, these rings resonantly enhance the cavity length, which results in ultra-narrow intrinsic linewidth, as low as 40 Hz.
Here, we present an overview on state-of-the-art developments regarding these lasers. We compare linewidth and tuning results for different feedback circuit configurations. Finally, we report on the first demonstration of a hybrid-integrated semiconductor laser that operates in the visible wavelength range.
Four years ago, the EU project PIX4life set out to mature an open access pilot line for silicon nitride integrated photonics, focused on life science applications. The synergies of industrial and academic project partners enabled the creation and validation of a unique pilot line using carefully selected demonstrator projects. Simultaneously, the software infrastructure (process design kits, design tools and building blocks) needed to enable early access of the pilot line through multi-project wafer (MPW) fabrication runs was created. After ten MPW fabrication runs in last three years at two foundries, and successful realization of dozens of designs from the project partners and the external customers, the pilot line is fully operational and ready for open access. In this presentation, we intend to share the experiences we have gained in setting up the pilot line, and to discuss the opportunities and challenges we can expect in future.
Visible diode lasers with wide wavelength tunability and narrow spectral linewidth are of high importance in bio-photonics and metrology. Hybrid integrated diode lasers, using waveguide circuits for spectrally selective feedback, provide wide tunability and sub-100-Hz intrinsic linewidths in a robust chip format. So far, these lasers have only been realized at infrared wavelengths. Here we present the first operation of a hybrid integrated diode laser in the visible. The laser, formed by a diode amplifier which is hybrid integrated with a Si3N4 ring-resonator based feedback circuit, is tunable over 11 nm around 685 nm and delivers 5 mW output power.
Ultra-narrow linewidth tunable hybrid integrated lasers are built from a combination of indium phosphide (InP) and silicon nitride-based TriPleX™. By combining the active functionality of InP with the ultra-low loss properties of the TriPleX™ platform narrow linewidth lasers in the C-band are realized. The InP platform is used for light generation and the TriPleX™ platform is used to define a long cavity with a wavelength-selective tunable filter. The TriPleX™ platform has the ability to adapt mode profiles over the chip and is extremely suitable for mode matching to the other platforms for hybrid integration. The tunable filter is based on a Vernier of micro-ring resonators to allow for single-mode operation, tunable by thermo-optic or stress-induced tuning. This work will show the operational principle and benefits of the hybrid lasers and the state of the art developments in the realization of these lasers. High optical powers ( <100 mW) are combined with narrow linewidth (< 1 kHz) spectral responses with tunability over a large (>100 nm) wavelength range and a low relative intensity (< -160 dB/Hz).
Evanescent field based integrated optics have great potential as a chip-based platform for label-free detection of molecular interactions. Implementation of the waveguides in an optical interferometric scheme allows for a very sensitive label-free sensor array platform as in this case small changes of the refractive index caused by the molecule capturing are easily detected. The unsurpassed sensitivity of especially the aMZI (asymmetric-Mach-Zehnder interferometer) sensor, in combination with the extreme uniformity of these sensing arrays allows for screening of proteins as well as small molecule drug candidates. However, to become interesting for the market, much more has to be in place: optimized surface functionalization chemistry, combination with microfluidics, and preferably hybrid integration of lightsource(s) and detector(s). In this proceedings the specific aMZI sensor chip design, surface modification, readout mechanisms and first results with multiplexing two specific cancer biomarker protein (POSTN and TGFBI) will be discussed. Initial experiments show a limit of detection of 1 ng/ml (~10 pM) of POSTN in buffer solution.
Photonic Integrated Circuit (PIC) technology is becoming more and more mature and the three main platforms that offer Multi Project Wafer runs (Indium Phosphide (InP), Silicon on Insulator (SOI) and the silicon nitride based TriPleX platform) each have their own unique selling points. New disruptive PIC based modules are enabled by combinations of the different platforms complementing each other in performance. In particular the InP-TriPleX combination are two very complementary technologies. Combining them together yields for instance tunable ultra-narrow linewidth lasers extremely suitable for telecom and sensing applications. Also microwave photonics modules for Optical Beam Forming Networks and 5G communication can, and have been realized with this combination. Important part of this combination is the integration of the different platforms in modules via cost effective assembly techniques. This talk will present the combination of both technologies, the interconnection issues faced in the assembly process and latest measurement results on these hybrid integrated devices.
We are reporting on a Multi-Color Laser Engine (MLE) multiplexing four wavelengths (405 nm, 488 nm, 561 nm, 640 nm) by means of a Photonic Integrated Circuit (PIC) with Silicon Nitride (SiN) waveguides. Multiple building blocks are tested that allow manipulating the light in the waveguides to achieve fiber switching and variable optical attenuation. To slow down facet degradation and extend chip lifetime at near Ultra-Violet (UV) wavelengths (405 nm), a lateral endcap is implemented on chip and tested for reliability. Reasonable coupling and on-chip losses have been achieved in view of a practical use of the technology.
Integrated-optical biosensors such as, for example, the microring resonator (MRR) and Mach-Zehnder interferometer, are more and more commercialized, mainly because of their high intrinsic sensitivity in combination with the possibilities they offer for integration in optofluidic devices. Previously, we have described the development and basic characteristics of MRR sensor chips that were fabricated in the TriPleX based silicon-nitride platform1 . In the present work, results are shown for the quantitative and sensitive detection of thrombin with aptamer-modified sensor chips. First, the modified MRR biosensor chips were tested for the binding and detection of thrombin using a repetitive number of binding/regeneration cycles on buffer sample containing 100 nM of thrombin. Then the binding curve was determined using different concentrations of thrombin, which revealed a limit of detection of 1 nM and a dynamic range up to roughly 0.5 μM of thrombin. Results from the thrombin binding experiment showed a stable performance during the course of multiple binding and regeneration cycles.
Silicon-Nitride based Photonic Integrated Circuits (PICs) broaden the application scope of PICs outside of telecommunications where it originated from, since the wavelength range over which a waveguide can be designed matches for instance biophotonic applications usually working in the VIS (400-700nm) and NIR (700-1000nm) range. In this paper we show the latest results our silicon-nitride based sensor platform, that consist of an array of several types of interferometric sensors (Microring resonators, Mach-Zehnder interferometers), that are either used as refractive index, absorption or fluorescence sensors. We show the trade-offs between the different sensor types and show why an asymmetric MZI improves the sensitivity of the sensor platform over the MRR with over a factor of 10 down to the 10-8 RIU level. Furthermore we show that using flip-chipped VCSELs as integrated light source a low cost, disposable device is made. For desktop purposes we show how light sources are fiber coupled to the sensing platform creating a high end measurement system. The complete readout system allows for measuring multiple sensors on the chip, enabling multi-analyte measurements as well as improve the total stability of the measurement platform by using on-chip references. Finally we show an overview of measurement results where the sensor platform is functionalized using different interaction layers both local as well as wafer- scale. The results that the sensor platform can be used in for example liquid (blood and saliva) analysis as well as bacteria detection. The platform can be extended with a microfluidic interface for interaction of the optical layer and fluidics. An added integrated on-chip spectrometer allow additional functionality to the presented sensing platform.
Photonics has become critical to life sciences. However, the field is far from benefiting fully from photonics' capabilities. Today, bulky and expensive optical systems dominate biomedical photonics, even though robust optical functionality can be realized cost-effectively on single photonic integrated circuits (PICs). Such chips are commercially available mostly for telecom applications, and at infrared wavelengths. Although proof-of-concept demonstrations for PICs in life sciences, using visible wavelengths are abundant, the gating factor for wider adoption is limited in resource capacity. Two European pilot lines, PIX4life and PIXAPP, were established to facilitate European R and D in biophotonics, by helping European companies and universities bridge the gap between research and industrial development. Through creation of an open-access model, PIX4life aims to lower barriers to entry for prototyping and validating biophotonics concepts for larger scale production. In addition, PIXAPP enables the assembly and packaging of photonic integrated circuits.
Photonic Integrated Circuits (PIC) will change the fundamental paradigms for the design of multi-color laser engines for life sciences. Exemplified with flow cytometry (FCM), integrated optical technology for visible wavelengths will be shown to open a new spectrum of possibilities to control flow cell illumination patterns, such as the number of output spots, the spot size, and even complex patterns generated by interferometry. Integration of additional optical functions such as variable optical attenuation, wavelength division multiplexing or fast shutters adds value to the PIC. TOPTICA is demonstrating integration of PICs in present Multi-color Laser Engine (MLE) architectures. Multiple wavelengths (405nm, 488nm, 561nm, 640nm) are coupled free space into the chip, leveraging its beam steering COOLAC (Constant Optical Output Level Auto Calibration) technology for automatic realignment, thus overcoming the need of fiber input delivery. Once in the waveguide, the light can be redirected and shaped to a desired output pattern and pitch, reducing the need of discrete optical components. In this work, we will discuss the implementation of various building blocks in PIC technology for MLEs and analyze the advantages over current macroscopic counterparts.
Photonic technology is increasingly used in applications in medicine, life and environmental science. Whereas currently many of these applications are implemented using some form of discrete (free-space) optics, much can be gained from a transition to Photonics Integrated Circuits. This follows the trends in the electronics industry where highly integrated electronic circuits have allowed the combination of many different functions in a small form factor. Just as it has done for the electronics industry, integrated optics will lead to smaller, cheaper, more reliable and more user friendly devices.
In this article a selection of highlights of the TriPleX™ technology of LioniX is given. The basic waveguide technology is explained with recent benchmark measurements done by University California Santa Barbara (UCSB) and University Twente (UT-TE). In order to show the low loss transparency over a wide wavelength range three examples of applications in different wavelength regimes are described in more detail. These are the Integrated Laser Beam Combiner (ILBC) of XiO Photonics in the visible light, a ringresonator sensing platform of LioniX around 850 nm and a phased array antenna with an Optical Beam Forming Network in the 1550 nm band. Furthermore it is shown that the technology is easily accessible via Multi Project Wafer Runs for which the infrastructure and design libraries are also set up.
We present a new class of low-loss integrated optical waveguide structures as CMOS-compatible industrial standard for photonic integration on silicon or glass. A TriPleXTM waveguide is basically formed by a -preferably rectangular- silicon nitride (Si3N4) shell filled with and encapsulated by silicon dioxide (SiO2). The constituent materials are low-cost stoichiometric LPVCD end products which are very stable in time. Modal characteristics, birefringence, footprint size and insertion loss are controlled by design of the geometry. Several examples of new applications will be presented to demonstrate its high potential for large-scale integrated optical circuits for telecommunications, sensing and visible light applications.
A new class of integrated optical waveguide structures ("TriPleX") is presented, based on low cost CMOS-compatible
LPCVD processing of alternating Si3N4 and SiO2 layers. The technology allows for medium and high index-contrast
waveguides that exhibit low channel attenuation. In addition, TriPleX waveguides are suitable for operation at
wavelengths from visible (< 500 nm) through the infra-red range (2 μm and beyond). The geometry is basically formed
by a rectangular cross-section of silicon nitride (Si3N4) filled with and encapsulated by silicon dioxide (SiO2). The
birefringence and minimal bend radius of the waveguide are completely controlled by the geometry of the waveguide
layer structures. Experiments on typical geometries show excellent characteristics for telecom wavelengths at ~1300 nm-1600 nm (channel attenuation ≤ 0.06 dB/cm, Insertion Loss (IL) ≤ 0.15 dB, Polarization Dependent Loss (PDL) ≤ 0.1 dB, Group Birefringence (Bg) << 1×10-4, bend radius ≤ 50-100 μm).
In the last years much effort has been taken to arrive at optical integrated circuits with high complexity and advanced functionality. For this aim high index contrast structures are employed that allow for a large number of functional elements within a given chip area: VLSI photonics. It is shown that optical microresonators can be considered as promising basic building blocks for filtering, amplification, modulation, switching and sensing. Active functions can be obtained by monolithic integration or a hybrid approach using materials with thermo-, electro- and opto-optic properties and materials with optical gain. Examples are mainly taken from work at MESA+.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.