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Method for removing polysilicon protection layer on a back face of an IGBT having a field stop structure

  • US 9,607,851 B2
  • Filed: 07/25/2013
  • Issued: 03/28/2017
  • Est. Priority Date: 07/26/2012
  • Status: Active Grant
First Claim
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1. A method for removing a polysilicon protection layer on a back face of an IGBT having a field stop structure, comprising:

  • thermally oxidizing the polysilicon protection layer on the back face of the IGBT until the oxidation is terminated on a gate oxide layer located above the polysilicon protection layer to form a SiO2 layer; and

    removing the formed SiO2 layer and the gate oxide layer by a dry etching process.

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