Method and apparatus for making shallow trench structure
US11901217B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2021 |
| Grant date | Feb 13, 2024 |
| Priority date | — |
| Expiry date | May 6, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76232
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present disclosure provides a method for making a shallow trench structure, which at least includes the following: preparing a substrate; forming a first material layer on one side of the substrate; forming a second material layer on the first material layer; forming a shallow trench in the second material layer, the first material layer and the substrate; performing a first lateral etching on the second material layer from the shallow trench to both sides by using wet etching; performing a second lateral etching on the first material layer from the shallow trench to both sides by using dry etching. The present disclosure solves the problem of the damage to the silicon in the shallow trench caused by the traditional lateral etching technology.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.