Patent · US Expired

Chemical method for producing smooth surfaces on silicon wafers

US6514875B1 · kind B1 · utility

1Cited by
13References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 28, 1997
Grant dateFeb 4, 2003
Priority date—
Expiry dateApr 28, 2017

Classification

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

Abstract

An improved method for producing optically smooth surfaces in silicon wafers during wet chemical etching involves a pre-treatment rinse of the wafers before etching and a post-etching rinse. The pre-treatment with an organic solvent provides a well-wetted surface that ensures uniform mass transfer during etching, which results in optically smooth surfaces. The post-etching treatment with an acetic acid solution stops the etching instantly, preventing any uneven etching that leads to surface roughness. This method can be used to etch silicon surfaces to a depth of 200 &mgr;m or more, while the finished surfaces have a surface roughness of only 15-50 å (RMS).

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