Shallow trench isolation structures and a method for forming shallow trench isolation structures
US7906407B2 · kind B2 · utility
4Cited by
6References
57Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 29, 2007 |
| Grant date | Mar 15, 2011 |
| Priority date | — |
| Expiry date | Jan 12, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76232
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A shallow trench isolation structure having a negative taper angle and a method for forming same. A silicon nitride layer formed over a semiconductor substrate is etched according to a plasma etch process to form a first opening therein having sidewalls that present a negative taper angle. The substrate is etched to form a trench therein underlying the first opening. Silicon dioxide fills both the opening and the trench to form the shallow trench isolation structure, with the silicon dioxide in the opening exhibiting a negative taper angle to avoid formation of conductive stringers during subsequent process steps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.