METAL PATTERN FORMING METHOD

Abstract

A method of forming a metal pattern comprising forming a metal film having a lower layer made of a metal and an upper layer made of a metal different from the metal of the lower layer, forming a resist film having a predetermined pattern on the upper layer, and patterning the metal film by etching the metal film using the resist film as a mask. Here, patterning the metal film comprises etching the upper layer, immersing the resist film and the upper layer in a pretreatment liquid containing a nonionic surfactant after the first etching process, and etching the lower layer after the immersing process.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.

FIG. 1 is a sectional view schematically illustrating a method of forming a metal pattern according to an embodiment of the invention.

Claims

1. A method of forming a metal pattern, the method comprising: forming a metal film with a lower and upper layer, with the lower layer and upper layer each made of a metal, the upper layer made from a metal different than the lower layer;forming a resist film on the upper layer according to a predetermined pattern; andforming a pattern on the metal film, the process of forming the pattern, comprising: etching the upper layer using an etchant and the resist film as a mask;immersing the resist film and the upper layer in a pretreatment liquid containing a nonionic surfactant; andetching the lower layer using an etchant and the resist film as a mask.

2. The method of forming a metal pattern according to claim 1, wherein immersing the resist film and the upper layer comprises immersing the resist film and upper layer in a pretreatment liquid having a temperature in the range of ±5° C. of the temperature of the etchant used to etch the lower layer.

3. The method of forming a metal pattern according to claim 1, wherein the concentration of the nonionic surfactant in the pretreatment liquid is 10 parts per million or more.

4. The method of forming a metal pattern according to claim 1, wherein the upper layer is made of a noble metal and the lower layer is made of a metal other than a noble metal.

5. The method of forming a metal pattern according to claim 4, wherein the upper layer is made of one of gold (Au) or platinum (Pt) and the lower layer is made of one of Nichrome (NiCr), nickel (Ni), tungsten (W), or tantalum (Ta).

6. The method of forming a metal pattern according to claim 1, wherein the etchant used to etch the lower layer of the metal film is an aqueous solution having a pH value of 4 or less.

7. The method of forming a metal pattern according to claim 1, wherein the resist film is formed from an alkali-soluble resin material.

8. A method of forming a metal pattern on a metal film comprised of an lower and upper layer, with the lower layer and upper layer each made of a metal, and the upper layer comprised of a metal different than the lower level, the method comprising: forming a resist film from a alkali-soluble resin material on the upper layer according to a predetermined pattern;etching the upper layer using an etchant and the resist film as a mask;immersing the resist film and the upper layer in a pretreatment liquid containing a nonionic surfactant; andetching the lower layer using an etchant and the resist film as a mask.

9. The method of forming a metal pattern according to claim 8, wherein immersing the resist film and the upper layer of the metal film comprises immersing the resist film and upper layer in a pretreatment liquid having a temperature in the range of ±5° C. of the temperature of the etchant used to etch the lower layer of the metal film.

10. The method of forming a metal pattern according to claim 8, wherein the concentration of the nonionic surfactant in the pretreatment liquid is 10 parts per million or more.

11. The method of forming a metal pattern according to claim 8, wherein the upper layer of the metal film is made of a noble metal and the lower layer of the metal film is made of a metal other than a noble metal.

12. The method of forming a metal pattern according to claim 11, wherein the upper layer is made of one of gold (Au) or platinum (Pt) and the lower layer is made of one of Nichrome (NiCr), nickel (Ni), tungsten (W), or tantalum (Ta).

13. The method of forming a metal pattern according to claim 8, wherein the etchant used to etch the lower layer of the metal film is an aqueous solution having a pH value of 4 or less.