Low-stress stencil masks using SOI substrates for EPL and LEEPL

Autor: Hiroshi Sugimura, Akira Tamura, Kojiro Itoh, Takashi Yoshii, Toshiaki Kurosu, Hideyuki Eguchi
Rok vydání: 2003
Předmět:
Zdroj: SPIE Proceedings.
ISSN: 0277-786X
DOI: 10.1117/12.504234
Popis: We focus on stencil mask technologies for the next generation lithography (NGL) options such as electron projection lithography (EPL) and low energy electron-beam proximity projection lithography (LEEPL). For the production of high-quality stencil masks, we selected silicon-on-insulator (SOI) substrate as desirable stencil mask material because of its availability and quality. We showed how the membrane stress varies with dopant concentration and our proposed theoretical prediction on stress dependency on dopant concentration is consistent with experimental data. From the experimental data and prediction, doping method using SOI substrates proved to be able to produce membranes with stress of less than 10 MPa. We also presented how the out-of-plane distortions (OPD) within a subfield depend on the doping profile and cantilever beams with a length of 200 um remained flat. And then we measured the image placement (IP) errors within a subfield on a 200-mm EPL mask, which was less than 20 nm. Finally we employed the doping method to LEEPL mask and presented stress data. Therefore, we confirmed the doping method using SOI substrate is proper approach to fabricate low-stress stencil masks for EPL and LEEPL.
Databáze: OpenAIRE