Paper
30 December 2003 Comparison of micro chrome patterns in gray-scale lithography
Kei Hanai, Yoshinori Matsumoto
Author Affiliations +
Abstract
Gray scale lithography is an attracting technology to fabricate 3D structures such as a microlens, prism etc. In this study, a gray scale chrome mask was fabricated by using image-processing software and E-beam lithography system that can use bitmap as drawing data. Random dither pattern and half-tone pattern by circles were generated as a fundamental micro pattern. UV exposure was performed on 10μm thick positive resist (AZ-p4620). The mask was distanced 80μm from the resist surface to defocus the micro pattern. As a result, half-tone pattern provides smooth surface while the surface condition of dither pattern had a horizontally large roughness. The resist depth was changed in the range of 20%-80% gray-scale value for the dither pattern, and in the little wider range of 20%-90% for the half-tone pattern. Then, Fresnel lens profile was formed by using half-tone pattern, which profile was calculated by C-code program and polar-coordinates conversion by image-processing software.
© (2003) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Kei Hanai and Yoshinori Matsumoto "Comparison of micro chrome patterns in gray-scale lithography", Proc. SPIE 5342, Micromachining and Microfabrication Process Technology IX, (30 December 2003); https://doi.org/10.1117/12.525019
Lens.org Logo
CITATIONS
Cited by 8 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Photomasks

Lithography

Fresnel lenses

Photography

Electron beam lithography

Raster graphics

Focus stacking software

Back to Top