Aqua regia and hydrogen peroxide HCL combination to remove Ni and NiPt residues

Patent metadata

Field	Value
Publication number	US-9399753-B2
Application number	US-201414574995-A
Country	US
Kind code	B2
Filing date	Dec 18, 2014
Priority date	Jun 5, 2012
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

Abstract

A method for cleaning residues from a semiconductor substrate during a nickel platinum silicidation process is disclosed, including a multi-step residue cleaning, including exposing the substrate to an aqua regia solution, followed by an exposure to a solution having hydrochloric acid and hydrogen peroxide. The SC2 solution can further react with remaining platinum residues, rendering it more soluble in an aqueous solution and thereby dissolving it from the surface of the substrate.

First claim

What is claimed is:

1. A formulation for processing nickel platinum, the formulation comprising:
water;
nitric acid mixed with the water; and
an organic acid mixed with the water and the nitric acid, the organic acid comprising carbonyl acid,
wherein a concentration of the nitric acid in the formulation is less than about 15 wt %.

2. The formulation of claim 1 , wherein the concentration of the nitric acid in the formulation is between about 3 wt % and about 10 wt %.

3. The formulation of claim 2 , wherein the concentration of the nitric acid in the formulation is about 7 wt %.

4. The formulation of claim 3 , wherein a temperature of the formulation is about 40° C.

5. The formulation of claim 2 , wherein the formulation does not comprise a chlorine-based acid.

6. A formulation for processing nickel platinum, the formulation comprising:
water;
nitric acid mixed with the water; and
carbonyl acid mixed with the water and the nitric acid,
wherein a concentration of the nitric acid in the formulation is between about 3 wt % and about 10 wt %.

7. The formulation of claim 6 , wherein the concentration of the nitric acid in the formulation is about 7 wt %.

8. The formulation of claim 7 , wherein a temperature of the formulation is between about 60° C. and about 100° C.

9. The formulation of claim 8 , wherein the temperature of the formulation is between about 60° C. and about 80° C.

10. A formulation for processing nickel platinum, the formulation comprising of:
water;
nitric acid mixed with the water; and
carbonyl acid mixed with the water and the nitric acid,
wherein a concentration of the nitric acid in the formulation is less than about 15 wt %.

11. The formulation of claim 10 , wherein a concentration of the nitric acid in the formulation is less than about 10 wt %.

12. The formulation of claim 11 , wherein a concentration of the nitric acid in the formation is greater than about 3 wt %.

13. The formulation of claim 12 , wherein a temperature of the formulation is about 60° C. and about 80° C.

Assignees

• Intermolecular Inc
• Globalfoundries Inc
• Intermolecular Inc

Inventors

• Duong Anh
• Fitz Clemens
• Karlsson Olov

Classifications

• H10P95/90

  Thermal treatments, e.g. annealing or sintering · CPC title

• H10P72/0411

  for wet cleaning or washing · CPC title

• H10P70/27

  during, before or after processing of conductive materials, e.g. polysilicon or amorphous silicon layers · CPC title

• H10P70/20

  Cleaning during device manufacture · CPC title

• H10D64/0131

  the additional conductive layer comprising a silicide layer formed by the silicidation reaction between the layer of silicon with a metal layer which is not formed by metal implantation · CPC title