Patent · US Expired

Low pressure chemical vapor deposition of silicon nitride films

US4395438A · kind A · utility

80Cited by
3References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 6, 1982
Grant dateJul 26, 1983
Priority date
Expiry dateDec 6, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/945
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A process for forming a silicon nitride layer on a semiconductor wafer in a low pressure chemical vapor deposition process. The wafer is disposed in a closed reaction chamber evacuated to a low pressure and heated to an elevated temperature in the range of about 650 to 900 degrees Centigrade. The interior of the chamber is supplied with a gaseous mixture of ammonia and a silicon compound adapted to react together with the ammonia at the elevated temperature to deposit a layer of silicon nitride on the wafer. The ammonia and the selected silicon compound have a ratio of relative concentrations in the mixture which is preselected to be in the range of 4:1 and 20:1. The silicon compound may be silane, dichlorosilane, or tetrachlorosilane. Using dichlorosilane, the preferred ratio of relative concentrations of ammonia and dichlorosilane is in the range of about 6:1 to 8:1.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.