Transparent refraction structure for an image sensor and methods of forming the same
US11749700B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 2021 |
| Grant date | Sep 5, 2023 |
| Priority date | — |
| Expiry date | Aug 28, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/8067
Abstract
A plurality of photovoltaic junctions for a subpixel may be formed in a semiconductor substrate. After thinning the backside of the semiconductor substrate, at least one transparent refraction structure may be formed on the backside surface of the thinned semiconductor substrate. Each transparent refraction structure has a variable thickness that decreases with a lateral distance from a vertical axis passing through a geometrical center of the second-conductivity-type pillar structures for the subpixel. A subpixel optics assembly including an optical lens may be formed over the at least one transparent refraction structure. Each transparent refraction structure may reduce the tilt angle of light that propagate downward into the photodetectors, and increases total internal reflection of light and increase the efficiency of the photodetectors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.