Method for forming a shallow trench isolation structure
US6344415B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 15, 1999 |
| Grant date | Feb 5, 2002 |
| Priority date | — |
| Expiry date | Sep 15, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76224
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming a STI structure. A pad oxide layer is formed over a substrate. An amorphous silicon layer is formed over the pad oxide layer. A mask layer is formed over the amorphous silicon layer. The mask layer is patterned, and then the amorphous silicon layer, the pad oxide layer and the substrate are etched in sequence to form a trench. A thermal oxidation is performed to form a liner layer along the exposed sidewalls of the amorphous silicon layer and the exposed substrate surface inside the trench. Insulation material is deposited over the substrate, completely filling the trench. A chemical-mechanical polishing step is performed to remove a portion of the insulation layer and a portion of the mask layer so that an insulation plug is formed inside the trench. After the polishing step, the top surface of the insulation plug and the top surface of the mask layer are at the same surface. The mask layer is patterned to expose a portion of the amorphous silicon layer near the central region of two neighboring trenches. An ion implantation is carried out. The mask layer is removed. The amorphous silicon layer is removed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.