Process for semiconductor device fabrication
US5814562A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1995 |
| Grant date | Sep 29, 1998 |
| Priority date | — |
| Expiry date | Nov 16, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/974
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention is directed to a process for fabricating a semiconductor integrated circuit device, and specifically, a process for cleaning a silicon substrate before gate silicon dioxide is formed on the silicon substrate. The gate silicon dioxide is used to form transistor gates. The process of the present invention provides a silicon/silicon dioxide interface and the bulk silicon dioxide with advantageous electrical properties. In the present process, the silicon substrate is first subjected to a stream of hydrofluoric acid (HF) vapor. The vapor HF stream is a mixture of anhydrous HF, methanol, and nitrogen. Following this, the substrate is subjected to gaseous chlorine that has been irradiated with broad band UV radiation. After the substrate has been cleaned according to the present process, a layer of silicon dioxide is grown thereon using conventional techniques such as rapid thermal oxidation (RTO). It is advantageous if the cleaned silicon surface is kept under high vacuum or in an inert gas environment before the oxide growth is commenced. In the context of the present process, it is advantageous if the substrate is maintained in an essentially oxygen-free atmosphe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.