CMOS with dual raised source and drain for NMOS and PMOS
US9087741B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 2011 |
| Grant date | Jul 21, 2015 |
| Priority date | — |
| Expiry date | Aug 23, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/0188
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An apparatus and a method for creating a CMOS with a dual raised source and drain for NMOS and PMOS. The spacers on both stack gates are of equal thickness. In this method, a first insulating layer is formed on the surface. The first region is then masked while the other region has the first layer etched away and has an epitaxial source and drain grown on the region. A second layer is formed to all exposed surfaces. The second region is then masked while the first region is etched away. The epitaxial source and drain is formed on the first region. The second region can also be masked by adding a thin layer of undoped silicon and then oxidize it. Another way to mask the second region is to use a hard mask. Another way to form the second source and drain is to use amorphous material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.