发明授权
- 专利标题: Method of forming an inverted lens in a semiconductor structure
- 专利标题(中): 在半导体结构中形成倒置透镜的方法
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申请号: US12056736申请日: 2008-03-27
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公开(公告)号: US08003428B2公开(公告)日: 2011-08-23
- 发明人: Terence Barrett , Jeffrey P. Gambino , Robert K. Leidy
- 申请人: Terence Barrett , Jeffrey P. Gambino , Robert K. Leidy
- 申请人地址: US NY Armonk
- 专利权人: International Business Machines Corporation
- 当前专利权人: International Business Machines Corporation
- 当前专利权人地址: US NY Armonk
- 代理机构: Scully, Scott, Murphy & Presser, P.C.
- 代理商 Anthony J. Canale
- 主分类号: H01L21/00
- IPC分类号: H01L21/00
摘要:
A flat-top convex-bottom lower lens is formed by first applying a positive tone photoresist over a silicon oxide layer and an optional metallic barrier layer thereupon in a back-end-of-line (BEOL) metallization structure. The positive tone photoresist is exposed under defocused illumination conditions and/or employing a half-tone mask so that a cross-sectional profile of the positive tone photoresist after exposure contains a continuous and smooth concave profile, which is transferred into the underlying silicon oxide layer to form a concave cavity therein. After removing the photoresist, the cavity is filled with a high refractive index material such as silicon nitride, and planarized to form a flat-top convex-bottom lower lens. Various aluminum metal structures, a color filter, and a convex-top flat-bottom upper lens are thereafter formed so that the upper lens and the lower lens constitute a composite lens system.