Patent · US Expired

Method for producing a silicon wafer

US7456106B2 · kind B2 · utility

22Cited by
3References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 1, 2004
Grant dateNov 25, 2008
Priority date
Expiry dateApr 20, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/30608
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Provided is a method for producing a silicon wafer whose surfaces exhibit precise flatness and minute surface roughness, and which allows one to visually discriminate between the front and rear surfaces, the method comprising a slicing step of slicing a single-crystal ingot into thin disc-like wafers, a chamfering step of chamfering the wafer, a lapping step for flattening the chamfered wafer, a mild lapping step for abrading away part of processing distortions on the rear surface of the wafer left after chamfering and lapping, a rear-surface mild polishing step for abrading away part of roughness on the rear surface of the wafer, an etching step for alkali-etching the remains of processing distortions on the front and rear surfaces of the wafer, a front-surface mirror-polishing step for mirror-polishing the front surface of the etched wafer, and a cleaning step for cleaning the mirror-polished wafer.

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