Patent · US Expired

Method of selectively etching high impurity concentration semiconductor layer

US4554046A · kind A · utility

18Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1984
Grant dateNov 19, 1985
Priority date
Expiry dateSep 19, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/32134
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for selectively etching a high impurity concentration semiconductor layer by making use of a difference in impurity concentration is disclosed. According to this method, the high impurity concentration semiconductor layer is exposed to an aqueous solution of a hydrogen fluoride-nitric acid-acetic acid-based etching solution while being subjected to ultrasonic-vibration.

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