Oxide etching method

• US 8,168,544 B2
• Filed: 07/18/2007
• Issued: 05/01/2012
• Est. Priority Date: 08/01/2006
• 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): Vinh, Lan
• Application Number:
  US12/305,099
• Publication Number:
  US 20090149030A1
• Time in Patent Office: 1,749 Days
• Field of Search: 438/745, 438/754, 438/756, 438/735, 438/738, 216/83, 216/103, 216/101, 216/10
• US Class Current: 438/754
• CPC Class Codes: C09K 13/04 containing an inorganic acid
• CPC Class Codes: C09K 13/06 with organic material
• CPC Class Codes: H01L 29/78693 the semiconducting oxide being amorphous
• CPC Class Codes: H01L 31/022475 composed of indium tin oxide [ITO]
• CPC Class Codes: H01L 31/022483 composed of zinc oxide [ZnO]
• CPC Class Codes: H01L 31/1804 comprising only elements of Group IV of the Periodic Table
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

There is provided an etching method of an amorphous oxide layer containing In and at least one of Ga and Zn, which includes etching the amorphous oxide layer using an etchant containing any one of acetic acid, citric acid, hydrochloric acid, and perchloric acid.

Claims

1. An etching method of an amorphous oxide in a structure comprising an ITO layer and an amorphous oxide layer, the method comprising etching the amorphous oxide layer, which comprises In and Ga, In and Zn, or In, Ga and Zn, using an etchant comprising any one of acetic acid, citric acid, hydrochloric acid, and perchloric acid at an etch rate larger than an etch rate of the ITO film.

4. The etching method of an amorphous oxide according to any one of claims 1-3, wherein a concentration of the acetic acid is 20 to 68% by weight, a concentration of the citric acid is 3.8 to 45% by weight, a concentration of the hydrochloric acid is 0.7 to 8.5% by weight, and a concentration of the perchloric acid is 5 to 44% by weight.

2. An etching method of an amorphous oxide in a structure comprising an oxide layer comprising In and Ga and an amorphous oxide layer, the method comprising etching the amorphous oxide layer, which comprises In and Zn or In, Ga, and Zn, using an etchant comprising any one of acetic acid, citric acid, hydrochloric acid, and perchloric acid at an etch rate larger than an etch rate of the oxide layer comprising In and Ga.

3. An etching method of an amorphous oxide in a structure comprising an oxide layer comprising In, Ga, and Zn and an amorphous oxide layer, the method comprising etching the amorphous oxide layer, which comprises In and Zn, using an etchant comprising any one of acetic acid, citric acid, hydrochloric acid, and perchloric acid at an etch rate larger than an etch rate of the oxide layer comprising In, Ga and Zn.