High aspect ratio shallow trench using silicon implanted oxide
US6576558B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2002 |
| Grant date | Jun 10, 2003 |
| Priority date | — |
| Expiry date | Oct 2, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76235
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A trench is etched through the layers of pad oxide and silicon nitride that have been deposited on a substrate, the patterned layer of photoresist is left in place. A tilt angle nitrogen implant is performed into the surface of the substrate, a deep shallow STI trench is etched into the surface of the substrate. An oxygen implant of moderate intensity is performed in the created STI trench, the photoresist is removed. An anneal is performed on the implanted oxygen. A liner oxide is grown within the opening, High Density Plasma (HDP) oxide is deposited inside the opening and the top surface of the remaining silicon oxide. CMP is performed to the surface of the HDP oxide down to the surface of the pad oxide that completes the formation of the STI region under the first embodiment of the invention. The invention can be further extended by creating a LOCOS layer at the bottom of the STI opening or by further etching the bottom of the STI opening. Both extensions are to be implemented prior to growing the oxide liner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.