Method of forming shallow trench isolation
US6207535A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 2000 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Mar 20, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/05
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of fabricating shallow trench isolations (STI) which forms a substrate with a patterned first oxide layer and a patterned silicon nitride layer thereon, so that active regions are defined with openings formed between the active regions. The openings are then over etched to form trenches for fabricating the STI, followed by forming a second oxide layer that conforms to a profile of the trenches. A third oxide layer is globally formed over the second oxide layer, sidewalls of the first oxide layer, and the silicon nitride layer. A thermal process is performed to densify a portion of the third oxide layer, so that a top portion of the third oxide layer is harder than a lower portion of the third oxide layer. The excessive portion of the third oxide layer above the silicon nitride layer is removed by performing chemical mechanical polishing, which planarizes a top surface of the third oxide layer in order to complete the manufacture of the STI.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.