Patent · US Expired

Plasma etching method and plasma etching system for carrying out the same

US6159388A · kind A · utility

14Cited by
6References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 26, 1998
Grant dateDec 12, 2000
Priority date
Expiry dateJan 26, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/67069
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Plasma etching method and apparatus for removing relatively thick portions from wafers by etching while measuring an actual etch quantity to thereby manufacture the wafers excellent in flatness quality on a mass-production basis. A conduit 20 of a plasma generator 2 is positioned above a relatively thick portion 111 of the wafer 110 to etch away a wafer material from the relatively thick portion 111 by ejecting a fluorine gas G. A laser beam L0 is emitted from a laser displacement meter 30 of a measuring apparatus 3 to detect an interference state between a reflected light beam L1 from the relatively thick portion 111 and a reflected light beam L2 form a reflecting plate 32 and count periodical changes of the interference state. When the count value m coincides with an integral value derived by dividing a desired etch quantity by a half wavelength of the laser beam L0, etching of the relatively thick portion 111 by the fluorine gas G is terminated.

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