A new laser scribing scheme for poly-Si based thin film solar cell is proposed. This technology consists of 1)
simultaneous removal of underlying TCO and poly-Si film, 2) electrical isolation by resin coating using inkjet and
3)selective top electrode removal by laser ablation of photoresist mask layer followed by chemical etching. Process
defects such as crack and parasitic melting can be eliminated by proposed patterning technology. This process can be
highly cost-effective because less laser patterning steps are required and less area for series interconnection is needed.
Poly-Si thin film solar cell was successfully fabricated and showed 7.4% of conversion efficiency.
Conventional patterning processes for series connection of silicon thin film solar cells are composed of laser scribing
processes, such as pattering of front electrode (P1), patterning of silicon thin films (P2) and patterning of silicon thin
films and back electrode (P3). However, we have proposed a new series connection scheme of silicon thin film solar
cells using direct inkjet patterning technology. The combination of laser scribing and inkjet printing technologies can
realize the series connected cell structure. After the deposition of silicon thin films without P1 process, both front
electrode and silicon thin films are patterned first by ultra violet (UV) laser scribing with the wavelength of 352 nm.
Then, to prevent the shunting between front and back electrodes, spacers were formed on the sidewalls of laser scribed
lines by inkjet printing. The series connected cells were fabricated by the following deposition of back electrode and P3
laser scribing process. In this research, we have developed the spacer formation process using the resin based dielectric
ink. Also, we have fabricated and characterized the amorphous silicon (a-Si) thin film solar modules with proposed
structure.
The cleaning of embedded-attenuated phase shift masks (EAPSMs) is one of the most important enabling capabilities in the production of high-quality masks. Particles are commonly generated during Cr and MoSiON etching using inductively coupled plasma (ICP) tools. The cleaning process of EAPSMs requires not only the removal of particles on the phase shifting layer (MoSiON) and glass, but also the ability to leave the phase and transmission properties intact.
Megasonic cleaning is a technique commonly used for removing particles on the surfaces of photomasks. However, megasonic processes employing SC-1 chemistry (specifically ammonium hydroxide) cannot be applied to a MoSiON PSM. Chemical erosion of the alkali-soluble phase shifting layer will drive phase and transmission performance outside of customer specifications. Therefore, EAPSM cleaning must balance simultaneously the complete removal of particles with the prevention physical damage. For these reasons, the cleaning process requires a high degree of control.
In this paper, a new cleaning method was applied to MoSiON-based masks utilizing megasonic cleaning because it had a little change on phase and transmission. Traditional SC-1 chemistry was not used at all. Results obtained through this method showed a little change on phase and transmission. The particles on glass also can be sufficiently removed using megasonic process with the dilute SC-1 chemistry. The cleaning technique for the fabrication of EAPSMs with no variation in phase and transmission after the cleaning process will be presented.
Reticle cleaning is one of the most important processes in photomask making, because the smallest particles on reticle are supposed to be printable on wafer. Moreover, the requirement for reticle cleaning is stricter, because reticle should be zero-defect and there is no killer factor on it. It is facing difficult challenges as it enters new era of 100 nm pattern, introducing DUV lithography and phase shift materials. As defect sizes are decreasing to be controlled in cleaning process, the cleaning performance depends on not only conventional chemical treatment and megasonics but also a new IPA drying method such as direct- displacement IPA vapor dry. So we investigated the cleaning performance with different IPA drying methods by using quartz, chrome, MoSiON mask blanks and several test plates with 70 percent and 30 percent quartz area in main pattern field , such as conventional IPA dry and direct-displace IPA vapor dry , catgorized particle sizes and analyzed residual elements composition after cleaning of two systems. Effectiveness of cleaning with different drying methods on HT PSMs has been also investigated by controlling phase and transmittance of KrF half-tone phase shift mask(HT PSM), within +/- 3 degrees and +/- 0.3 percent respectively. Finally, direct-displacement IPA vapor dry method with traditional chemical treatment presents better removal rate of particles than conventional IPA dry when it comes to remove the smallest particles on quartz and chrome. It is found that direct-displacement IPA vapor dry for reticle cleaning would be considered to be the alternative dry method to control the smallest particles for the high-grade photomasks.
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.