Method of dry etching oxide semiconductor film

• US 7,767,106 B2
• Filed: 07/10/2007
• Issued: 08/03/2010
• Est. Priority Date: 08/09/2006
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Chang, Chienliu
• Primary Examiner(s): Tran; Binh X
• Application Number:
  US11/775,561
• Publication Number:
  US 20080038929A1
• Time in Patent Office: 1,120 Days
• Field of Search: 216/63, 216/71, 216/72, 216/76
• US Class Current: 216/63
• CPC Class Codes: H01L 31/022466 made of transparent conductive layers, e.g. TCO, ITO layers
• CPC Class Codes: H01L 31/022483 composed of zinc oxide [ZnO]
• CPC Class Codes: H01L 31/1884 Manufacture of transparent electrodes, e.g. TCO, ITO
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

Provided is a dry etching method for an oxide semiconductor film containing at least In, Ga, and Zn, which includes etching an oxide semiconductor film in a gas atmosphere containing a halogen-based gas.

Claims

1. A method of dry etching an oxide semiconductor film including In, Ga, and Zn, which comprises performing etching in a gas atmosphere containing a halogen-based gas, wherein a reaction pressure during the etching is within a range of 0.6 Pa or more and 2.4 Pa or less, and wherein a bias RF power is applied at a density of 0.02 W/cm² or more to a substrate side during the etching.

2. The dry etching method according to claim 1, wherein a surface temperature the oxide semiconductor film during the etching is maintained at a temperature within a range of 0°

C. or more and less than 200°

C.

3. The dry etching method according to claim 1, wherein the oxide semiconductor film has an electron carrier concentration of less than 10¹⁸/cm³.

4. The dry etching method according to claim 1, wherein the oxide semiconductor film has a thickness within a range of 5 nm or more and 400 nm or less.

5. The dry etching method according to claim 1, wherein the gas atmosphere additionally contains Ar gas in an amount no greater than 25% by volume.

6. The dry etching method according to claim 1, wherein the etching is performed while covering a part of a surface of the oxide semiconductor film with an etching mask comprising a material selected from the group consisting of an organic photoresist, silicon oxide, amorphous silicon, and silicon nitride.

7. The dry etching method according to claim 6, wherein the etching mask has a thickness which is equal to or larger than a thickness of the oxide semiconductor film.