MOSFET device fabrication method capable of allowing application of self-aligned contact process while maintaining metal gate to have uniform thickness
US6436775B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 2001 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Jun 20, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3212
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The MOSFET fabrication method allows application of a self-aligned contact (SAC) process while maintaining a metal gate, such as a tungsten gate, to have a uniform thickness. The process involves forming a metal oxide film during the formation of a metal gate structure of the MOSFET device. The metal oxide film is formed by subjecting the gate structure through a rapid thermal oxidation (RTO) treatment and then to an N2O plasma treatment. The treatments allow the thickness of the metal oxide to be precisely controlled. The metal oxide acts as an insulator, which prevents electrical shorts between the gate structure and a contact plug even if a misalignment of occurs during the SAC process. This is an improvement from the conventional practice of separately forming a SAC barrier film after the formation of the metal gate structure and thus saves money, time, and increases reliability and productivity. Also the performance characteristics of the device is enhanced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.