Method of monolithic integration of hyperspectral image sensor

US10157956B2 · kind B2 · utility

Assignee

• INSTITUTE OF MICROELECTRONICS OF THE CHINESE ACADEMY OF SCIENCES · CN

Inventors

• Hushan Cui · 安丰镇, CN
• Jinjuan Xiang · Beijing, CN
• Xiaobin He · Los Angeles, US
• Tao Yang · Zhejiang, CN
• Junfeng Li · Nanhu, CN
• Chao Zhao · Thuwal, SA

Key dates

• Filing date: Apr 3, 2017
• Grant date: Dec 18, 2018
• Expiry date: Apr 3, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F77/413

Abstract

A method for monolithic integration of a hyperspectral image sensor is provided, which includes: forming a bottom reflecting layer on a surface of the photosensitive region of a CMOS image sensor wafer; forming a transparent cavity layer composed of N step structures on the bottom reflecting layer through area selective atomic layer deposition processes, where N=2m, m≥1 and m is a positive integer; and forming a top reflecting layer on the transparent cavity layer. With the method, non-uniformity accumulation due to etching processes in conventional technology is minimized, and the cavity layer can be made of materials which cannot be etched. Mosaic cavity layers having such repeated structures with different heights can be formed by extending one-dimensional ASALD, such as extending in another dimension and forming repeated regions, which can be applied to snapshot hyperspectral image sensors, for example, pixels, and greatly improving performance thereof.