Patent · US Expired

Plasma ashing method with oxygen pretreatment

US5560803A · kind A · utility

12Cited by
4References
13Claims
0Family size

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Key dates

Filing dateNov 30, 1994
Grant dateOct 1, 1996
Priority date
Expiry dateNov 30, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/427
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for ashing a resist on a wafer in a plasma reaction chamber comprises the steps of flowing a non-activated oxygen containing gas into the plasma reaction chamber immediately before loading the wafer to the plasma reaction chamber, and then carrying out a plasma ashing of the resist. In one of the preferred embodiments, after the reaction chamber was exposed to the atmosphere and then evacuated to vacuum, a mixed gas of oxygen (90% in volume) and water vapor (10% in volume) was flown into the reaction chamber with 1000 seem and 1 Torr for 5 min. and subsequently the ashing was carried out. The method prevents the ashing rate from decreasing with ashing time.

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