Method of forming shallow trench isolation structures
US6150235A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 2000 |
| Grant date | Nov 21, 2000 |
| Priority date | — |
| Expiry date | Jan 24, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/038
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming shallow trench isolation (STI) structures on a semiconductor substrate is disclosed. First a semiconductor substrate with a first area and a second area adjacent to the first area is provided. A mask layer is formed on the substrate, and is etched to expose portions of the substrate. A first photoresist is formed to cover the second area for exposing the first area. A first implanting procedure is performed with a titled angle to form first doping areas on the substrate encroaching into portions of the substrate covered by the first photoresist. The first photoresist is removed. A second photoresist is formed on the substrate to cover the first area for exposing the second area. And a second implanting procedure is done with a titled angle to form second doping areas on the substrate encroaching into portions of the substrate covered by the second photoresist. The second photoresist is removed. The substrate is etched to remove the first doping areas and the second doping areas for forming trench structures therein. It is noted that portions of the first doping areas and the second doping areas are residual in upper portions of sidewalls of the trench structure…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.