Method for semiconductor selective etching and BSI image sensor
US9362332B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 2014 |
| Grant date | Jun 7, 2016 |
| Priority date | — |
| Expiry date | Nov 14, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/8063
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of selectively etching a semiconductor device and manufacturing a BSI image sensor device includes etching a doped silicon substrate with an HNA solution for a predetermined time duration to obtain an etching solution having a concentration C1 of nitrite ions, etching the semiconductor device using the obtained etching solution. Etching the semiconductor device requires an initial concentration C0 of nitride ions that is lower than C1. The HNA solution comprises a hydrofluoric acid (HF), a nitric acid (HNO3), and a acetic acid (CH3COOH). The BSI image sensor device will have a uniform thickness when etched using the thus obtained etching solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.