Post chemical mechanical planarization (CMP) cleaning

Patent metadata

Field	Value
Publication number	US-11560533-B2
Application number	US-201916444490-A
Country	US
Kind code	B2
Filing date	Jun 18, 2019
Priority date	Jun 26, 2018
Publication date	Jan 24, 2023
Grant date	Jan 24, 2023

Abstract

Provided are formulations that offer a high cleaning effect on inorganic particles, organic residues, chemical residues, reaction products on the surface due to interaction of the wafer surface with the Chemical Mechanical Planarization (CMP) slurry and elevated levels of undesirable metals on the surface left on the semiconductor devices after the CMP. The post-CMP cleaning formulations comprise one or more organic acid, one or more polymer and a fluoride compound with pH<7 and optionally a surfactant with two sulfonic acid groups.

First claim

The invention claimed is:

1. A post Chemical Mechanical Planarization (CMP) cleaning composition consisting essentially of:
1 to 30 wt. % citric acid or salts thereof;
1 to 25 wt. % of a fluoride compound selected from the group consisting of ammonium fluoride, ammonium bifluoride, quaternary ammonium fluoride and combinations thereof;
0.1 to 3 wt. % of at least one polymeric additive selected from a group consisting of acrylic acid-acrylamido propane sulfonic acid copolymer polymer comprising polyethylene glycol, polypropylene glycol; and combinations thereof; and
water;
optionally
a surfactant having two or more sulfonic acid groups;
biological preservative selected from the group consisting of methylisothiazolinone, methylchloroisothiazolinone, benzisothiazolinone, and combinations thereof;
and
pH adjusting agent;
wherein the composition has a pH of between 1 to 7.

2. The post CMP cleaning composition of claim 1 , wherein the polymeric additive has a molecular weight range between 100-1,000,000.

3. The post CMP cleaning composition of claim 1 , wherein the post CMP cleaning composition is optionally diluted with DI water 2 to 500 times at point of use.

4. The post CMP cleaning composition of claim 1 , wherein the post CMP cleaning composition comprises 0.0001 wt. % to 10 wt. % a surfactant; wherein the surfactant is stable in the composition having conductivity of ≥40 mS/cm without any turbidity or precipitation.

5. The post CMP cleaning composition of claim 1 , wherein the surfactant comprises at least two negatively charged anionic groups.

6. The post CMP cleaning composition of claim 1 , wherein the surfactant is a diphenyl disulfonic acid or its salt having a structure of

wherein R is selected from H, or a linear or branched alkyl group with carbon chain length between 1 and 20.

Assignees

• Versum Mat Us Llc

Inventors

• Tamboli Dnyanesh C

Classifications

• H10P70/277

  the processing being a planarisation of conductive layers · CPC title

• H10P70/237

  the processing being a planarisation of insulating layers · CPC title

• C11D1/02

  Anionic compounds {(C11D1/002, C11D1/004, C11D1/008 take precedence)} · CPC title

• C11D1/22

  derived from aromatic compounds · CPC title

• C11D3/2079 Primary

  Monocarboxylic acids-salts thereof · CPC title