Method of manufacturing a substrate for an electronic device by using etchant and electronic device having the substrate

• US 20020045351A1
• Filed: 09/05/2001
• Published: 04/18/2002
• Est. Priority Date: 10/23/1998
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Jo, Gyoo Chul
• Granted Patent: US 7,202,165 B2
• Time in Patent Office: Days
• US Class Current: 438/694
• CPC Class Codes: C23F 1/02 Local etching
• CPC Class Codes: C23F 1/20 for etching aluminium or alloys thereof
• CPC Class Codes: H01L 21/32134 by liquid etching only
• CPC Class Codes: H01L 29/66765 Lateral single gate single channel transistors with inverted structure, i.e. the channel layer is formed after the gate

Abstract

In the case that a stacked layer, in which another metal layer is stacked on an Al layer or Al alloy layer having a low resistance, is used as a wiring material, an etchant is provided which can etch to a substantially equal etching rate by executing only one etching on the each metal layer composing the stacked layer. A method of manufacturing a substrate for an electronic device uses the etchant, producing an electronic device having the substrate.

In order to achieve the object, the etchant has fluoric acid, periodic acid and sulfuric acid wherein the total weight ratio of the fluoric acid and periodic acid is 0.05˜30 wt %, the weight ratio of the sulfuric acid is 0.05˜20 wt %, the weight ratio of periodic acid to fluoric acid is 0.01˜2 wt %. Also each layer of wiring (5,12,14) formed by stacking Al layer or Al alloy layer and Ti layer or Ti alloy layer can be uniformly etched to substantially equal etching rate by the etchant.

Claims

1. A method of manufacturing a substrate for electronic device comprising the steps of:

forming a wiring layer having an Al layer or Al alloy layer and a Ti layer or Ti alloy layer on a substrate;

providing a mask on said wiring layer; and

etching said wiring layer by using a etchant, the etchant including a fluoric acid, a periodic acid and a sulfuric acid in which the total weight ratio of the fluoric acid and the periodic acid is 0.05˜

30 wt %, the weight ratio of the sulfuric acid is 0.05˜

20 wt %, the weight ratio of the periodic acid to fluoric acid is 0.01˜

2 wt %.

2. The method according to claim 1, in which said wiring layer is etched to substantially equal etching rate.

3. An electronic device comprising:

a substrate manufactured by using an etchant including a fluoric acid, a periodic acid and a sulfuric acid, in which the total weight ratio of the fluoric acid and the periodic acid is 0.05˜

30 wt %, the weight ratio of the sulfuric acid is 0.05˜

20 wt %, the weight ratio of the periodic acid to fluoric acid is 0.01˜

2 wt; and

by etching a wiring layer of an Al layer or Al alloy layer and a Ti layer or Ti alloy layer.

4. The device according to claim 3, in which said wiring layer is etched to substantially equal etching rate.