Stripping solution for photolithography and pattern formation method

Patent metadata

Field	Value
Publication number	US-9436094-B2
Application number	US-201314026407-A
Country	US
Kind code	B2
Filing date	Sep 13, 2013
Priority date	Sep 24, 2012
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

A stripping solution for photolithography which can effectively strip away residual materials of a photoresist pattern and etching residual materials, and has excellent anticorrosion properties on SiO 2 and a variety of metal materials; and a method for forming a pattern using the stripping solution. A prescribed basic compound is used as a counter amine of the hydrofluoric acid contained in the stripping solution for photolithography, and the stripping solution for photolithography is adjusted to a pH measured at 23° C. of not more than 6.0 or 8.5 or more.

First claim

What is claimed is:

1. A stripping solution for photolithography comprising (A) hydrofluoric acid, (B) a basic compound represented by the following general formula (b-1), and (C) water, and having a pH at 23° C. of not more than 6.0, or 8.5 or more:

wherein
R 1b to R 5b each independently represent a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms, which may be substituted with a hydroxyl group, a carboxyl group, an amino group, or a phosphonic acid group, provided that at least one of R 1b to R 5b represents a hydrogen atom, and one of R 1b to R 4b may bind with R 5b to form a ring structure;
Y 1b and Y 2b each independently represent an alkylene group having from 1 to 3 carbon atoms;
n is an integer of from 1 to 5; and
when n is 2 or greater, a plurality of R 5b s may be the same as or different from each other, a plurality of Y 1b s may be the same as or different from each other, and R 5b s may bind with each other to form a ring structure, wherein a content of (B) the basic compound in the stripping solution is from 0.01 to 2.00% by mass.

2. The stripping solution for photolithography according to claim 1 , further comprising (D) a pH adjuster.

3. The stripping solution for photolithography according to claim 1 , further comprising (E) a water-soluble organic solvent.

4. The stripping solution for photolithography according to claim 1 , wherein a ratio of the normality of the basic compound to the normality of the hydrofluoric acid is from 0.1 to 3.0.

5. The stripping solution for photolithography according to claim 1 , wherein the stripping solution is used for forming a metal wiring pattern on a substrate provided with an insulating film made of SiO 2 .

6. The stripping solution for photolithography according to claim 1 , wherein R 1b to R 5b each independently represent a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms, which may be substituted with a hydroxyl group or an amino group.

7. The stripping solution for photolithography according to claim 1 , wherein (B) the basic compound represented by the general formula (b-1) is a compound represented by the following general formula (b-2):

wherein, Y 1b , Y 2b and n are as defined in the general formula (b-1).

8. A method of forming a pattern, comprising etching a substrate using a photoresist pattern provided on the substrate as a mask; then ashing the photoresist pattern; and thereafter stripping away residual materials of the photoresist pattern and etching residual materials using the stripping solution for photolithography according to claim 1 .

9. A stripping solution for photolithography comprising (A) hydrofluoric acid, (B) a basic compound represented by the following general formula (b-1), and (C) water and having a pH at 23° C. of not more than 6.0 or 8.5 or more:

wherein
R 1b to R 5b each independently represent a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms, which may be substituted with a hydroxyl group, a carboxyl group, or an amino group, provided that at least one of R 1b to R 5b represents a hydrogen atom, and one of R 1b to R 4b may bind with R 5b to form a ring structure;
Y 1b and Y 2b each independently represent an alkylene group having from 1 to 3 carbon atoms;
n is an integer of from 1 to 5; and
when n is 2 or greater, a plurality of R 5b s may be the same as or different from each other, a plurality of Y 1b s may be the same as or different from each other, and R 5b s may bind with each other to form a ring structure, and
a content of (B) the basic compound in the stripping solution is from 0.01 to 2.00% by mass.

10. A method of forming a pattern, comprising etching a substrate using a photoresist pattern provided on the substrate as a mask; then ashing the photoresist pattern; and thereafter stripping away residual materials of the photoresist pattern and etching residual materials using the stripping solution for photolithography according to claim 9 .

Assignees

• Tokyo Ohka Kogyo Co Ltd

Inventors

• Ueno Naohisa
• Mori Daijiro
• Haraguchi Takayuki

Classifications

• G03F7/426

  containing organic halogen compounds; containing organic sulfonic acids or salts thereof; containing sulfoxides · CPC title

• G03F7/425 Primary

  containing mineral alkaline compounds; containing organic basic compounds, e.g. quaternary ammonium compounds; containing heterocyclic basic compounds containing nitrogen · CPC title