In EUV (Extreme Ultraviolet) lithography processes for next-generation semiconductor device fabrication, insufficient EUV exposure light source power results in high costs due to low productivity. To increase the productivity of EUV lithography, Tokyo Electron Kyushu Ltd. successfully developed a module to increase resist sensitivity while maintaining resolution and line roughness by using Photosensitized Chemically Amplified ResistTM (PSCARTM) materials and processes. By utilizing the "Resist Sensitization Module”, productivity of EUV lithography is expected to improve, which lowers manufacturing costs of semiconductor devices.
Development of Resist Sensitization Module
JST (President, Michinari Hamaguchi) certified the successful development of a "Module for improvement of resist performance for lithography” (hereinafter referred to as "Resist Sensitization Module") as a topic of "Newly extended Technology Transfer Program (NexTEP)”.
Based on the research results of Prof. Seiichi Tagawa et al. of The Institute of Scientific and Industrial Research, Osaka University, JST had entrusted the development of the module to Tokyo Electron Kyushu Ltd. (President and Representative Director, Shinichi Hayashi) from March 2014 to March 2018.
EUV lithography (Note 1), with a wavelength of 13.5 nm, is ready to be introduced for mass production as a key technology for next-generation lithography to manufacture advanced semiconductor devices. However, in EUV lithography, insufficient exposure light source intensity results in low productivity and high cost. In order to compensate for low EUV light source intensity, resist material (Note 2) having high sensitivity is desired.
The concept of the Photosensitized Chemically Amplified ResistTM (PSCARTM) (Note 3), proposed by Osaka University, improves resist sensitivity while maintaining resolution and line roughness. Through this research in NexTEP, the "Resist Sensitization Module" for PSCAR was developed to improve the sensitivity of resist for EUV lithography. Basic performance of the module was verified with focus on mass production of semiconductor devices by using PSCAR.
Further improvement activities of materials and processes toward mass production of semiconductor devices will be done with related companies / consortia.
- Note 1) EUV lithography
- Technique for forming a resist pattern using a wavelength of 13.5 nm. The shorter the exposure wavelength, the finer resist pattern can be formed.
- Note 2) Resist material
- A film used for patterning a semiconductor device. A pattern shape is formed by exposure and development. After forming the resist pattern, etching process is performed to obtain patterns necessary for device formation. After the etching treatment, the resist is removed.
- Note 3) Photosensitized Chemically Amplified ResistTM (PSCARTM)
- PSCAR is a special chemically amplified resist (Note 4) to be sensitized by UV flood exposure with assist of photosensitization reactions. By forming a photosensitizer with the generation of acid at the pattern exposed area in a resist, the resist area with photosensitizer can be sensitized by photosensitization reactions at the subsequent UV flood exposure. This resist sensitization causes higher sensitivity than conventional chemically amplified resist.
* PSCARTM and Photosensitized Chemically Amplified ResistTM are trademarks of Tokyo Electron Ltd. and Osaka University.
- Note 4) Chemically amplified resist
- High sensitivity resist which chemically amplifies the reaction by catalytic chain reaction caused by acid generated in the pattern exposed area in a resist.
Research Theme “Module for improvement of resist performance for lithography”
Tokyo Electron Kyushu Ltd.
Department of Industry-Academic Collaboration, JST