×

Manufacturing method of semiconductor device with conductive film in opening through multiple insulating films

  • US 9,818,849 B2
  • Filed: 10/29/2014
  • Issued: 11/14/2017
  • Est. Priority Date: 06/17/2011
  • Status: Expired due to Fees
First Claim
Patent Images

1. A manufacturing method of a semiconductor device, comprising:

  • forming a semiconductor film that comprises a channel formation region comprising an oxide semiconductor, and an electrode film electrically connected to the semiconductor film;

    forming a first insulating film in contact with the semiconductor film and over the electrode film, the first insulating film comprising one of a silicon oxide, a silicon oxynitride, and a silicon nitride oxide;

    forming a second insulating film over the first insulating film, the second insulating film comprising an aluminum oxide;

    forming an etching mask including a first opening portion over the second insulating film;

    forming a second opening portion exposing the electrode film by etching a first portion of the first insulating film and a second portion of the second insulating film using an etching gas comprising carbon and fluorine, so that an angle between a side surface of the first insulating film and a bottom surface of the first insulating film at the second opening portion is larger than an angle between a side surface of the second insulating film and a bottom surface of the second insulating film at the second opening portion, wherein the first portion and the second portion overlap with the first opening portion;

    reducing unevenness of a side surface of the second opening portion by argon plasma treatment;

    removing the etching mask; and

    after reducing the unevenness, forming a conductive film in the second opening portion,wherein the first insulating film is an insulating film whose oxygen is partly released by heating,wherein the second insulating film has a higher gas barrier property than the first insulating film, andwherein an etching selectivity of the first insulating film is higher with respect to the second insulating film when etching with the same etching agent.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×