Method for fabricating MOS transistor having dual gate
US6326252A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 11, 2000 |
| Grant date | Dec 4, 2001 |
| Priority date | — |
| Expiry date | Jan 11, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/038
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods of forming a MOS transistor having dual gates minimizes impurity channeling and diffusion that can occur during impurity injection and activating processes. A method of fabricating the transistor includes the steps of forming a first conduction type well and a second conduction type well in a semiconductor substrate having an isolation region and an active region formed therein. Then, a gate oxide film is formed on an entire surface of the substrate, and a polysilicon layer is deposited on the gate oxide film preferably at a temperature of about 660.degree. C. to about 700.degree. C. and a pressure of about 10 to about 300 Torr. Next, portions of the polysilicon layer and the gate oxide film are selectively removed to form a gate electrode on each of the wells. Impurity ions are injected, having a conduction type opposite a conduction type of the corresponding well, into an exposed surface of each of the wells, to form lightly doped impurity regions. Insulating film sidewalls are formed at sides of each of the gates. Then, first conduction type impurity ions are heavily injected into a surface of the exposed first conduction type well and into the gate electrode formed on t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.