Fabrication method of semiconductor wafer
US7029977B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Mar 5, 2004 |
| Grant date | Apr 18, 2006 |
| Priority date | — |
| Expiry date | Apr 23, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/405
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A fabrication method of a semiconductor wafer can fill trenches formed in a semiconductor substrate with an epitaxial film with high crystal quality without leaving cavities in the trenches. The trenches are formed in the first conductivity type semiconductor substrate. Planes exposed inside the trenches are made clean surfaces by placing the substrate in a gas furnace, followed by supplying the furnace with an etching gas and carrier gas, and by performing etching on the exposed planes inside the trenches by a thickness from about a few nanometers to one micrometer. The trenches have a geometry opening upward through the etching. Following the etching, a second conductivity type semiconductor is epitaxially grown in the trenches by supplying the furnace with a growth gas, etching gas, doping gas and carrier gas, thereby filling the trenches. Instead of making the trenches slightly-opened upward, their sidewalls may be made planes enabling facet formation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.