Patent · US Expired

Method of forming a semiconductor device having several gate levels

US4724218A · kind A · utility

3Cited by
5References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 12, 1986
Grant dateFeb 9, 1988
Priority date
Expiry dateJun 12, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D44/041
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

The invention provides a method for forming a semiconductor device having several gate levels, which, in the case of forming a device with two gate levels, comprises the following steps: PA0 1. on a semiconductor substrate are deposited a dielectric layer, then a layer of material in which the gates of the first level are to be formed and a dielectric layer; PA0 2. the gates of the first level are formed by etching the two upper layers; PA0 3. the sides of the gates of the first level are isolated; PA0 4. a second layer is deposited of material in which the gates of the second level are to be formed; PA0 5. in this second layer an opening is formed giving access to the dielectric layer covering the top of the gates of the first level; PA0 6. by plasma etching or by chemical etching the zones of said second layer which overhang the gates of the first layer are removed by etching them simultaneously on their internal and external faces.

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