Method for raising polishing pad and polishing method

Patent metadata

Field	Value
Publication number	US-10307885-B2
Application number	US-201615541562-A
Country	US
Kind code	B2
Filing date	Jan 5, 2016
Priority date	Feb 4, 2015
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

A method for raising a polishing pad for polishing a silicon wafer, wherein a polishing pad made of foamed urethane resin is attached to a polishing machine, after dressing is performed, dummy polishing is performed, after processing to remove the polishing residues that have built up in the polishing pad by the dummy polishing is then performed, an amount of polishing residues in the polishing pad is measured, and a rise of the polishing pad subjected to the dummy polishing is judged based on the measured amount of polishing residues. As a result, a method for raising a polishing pad can improve the particle level in the polishing pad life early stage.

First claim

The invention claimed is:

1. A method for raising a polishing pad for polishing a silicon wafer, wherein
a polishing pad made of foamed urethane resin is attached to a polishing machine,
after dressing is performed, dummy polishing is performed,
after processing to remove polishing residues that have built up in the polishing pad by the dummy polishing is then performed, an amount of polishing residues in the polishing pad is measured, and
a rise of the polishing pad subjected to the dummy polishing is judged based on the measured amount of polishing residues, and wherein
the judgment is made as follows:
by performing polishing of a silicon wafer by using a reference polishing pad made of foamed urethane resin separately subjected only to dressing, processing to remove polishing residues which is performed by the same means as that used in the removal processing after the dummy polishing, and measurement of an amount of polishing residues after the removal processing, the amount of polishing residues in the reference polishing pad at a point in time at which a value of, i.e., an amount of time the reference polishing pad was used÷a previously set life of the reference polishing pad, is 0.05 is determined as a reference value in advance, and,
if the amount of polishing residues measured after the dummy polishing and the removal processing is greater than or equal to the reference value, a judgment is made that the polishing pad subjected to the dummy polishing has risen.

2. The method for raising a polishing pad according to claim 1 , wherein
the amount of polishing residues is measured by detecting a signal containing a Si—Kα ray from a fluorescent X-ray spectrum which is obtained by a fluorescent X-ray analysis method.

3. The method for raising a polishing pad according to claim 2 , wherein
the processing to remove polishing residues is performed by dressing and high-pressure jet water cleaning.

4. The method for raising a polishing pad according to claim 1 , wherein
the processing to remove polishing residues is performed by dressing and high-pressure jet water cleaning.

5. The method for raising a polishing pad according to claim 1 , wherein
the polishing machine is a double-side polishing machine.

6. A method for polishing a silicon wafer by using a polishing pad, wherein
a polishing pad made of foamed urethane resin is attached to a polishing machine,
after dressing is performed, dummy polishing is performed,
after processing to remove polishing residues that have built up in the polishing pad by the dummy polishing is then performed, an amount of polishing residues in the polishing pad is measured,
a polishing pad that is used in polishing of the silicon wafer is selected based on the measured amount of polishing residues, and
polishing of the silicon wafer is performed by using the selected polishing pad, and wherein
the selection is made as follows:
by performing polishing of a silicon wafer by using a reference polishing pad made of foamed urethane resin separately subjected only to dressing, processing to remove polishing residues which is performed by the same means as that used in the removal processing after the dummy polishing, and measurement of an amount of polishing residues after the removal processing, the amount of polishing residues in the reference polishing pad at a point in time at which a value of, i.e., an amount of time the reference polishing pad was used÷a previously set life of the reference polishing pad, is 0.05 is determined as a reference value in advance, and
a polishing pad whose amount of polishing residues measured after the dummy polishing and the removal processing is greater than or equal to the reference value is selected as a polishing pad that is used in polishing of the silicon wafer.

7. The polishing method according to claim 6 , wherein
the amount of polishing residues is measured by detecting a signal containing a Si—Kα ray from a fluorescent X-ray spectrum which is obtained by a fluorescent X-ray analysis method.

8. The polishing method according to claim 7 , wherein
the processing to remove polishing residues is performed by dressing and high-pressure jet water cleaning.

9. The polishing method according to claim 6 , wherein
the processing to remove polishing residues is performed by dressing and high-pressure jet water cleaning.

10. The polishing method according to claim 6 , wherein
the polishing machine is a double-side polishing machine.

Assignees

• Shinetsu Handotai Kk

Inventors

• Sasaki Takuya
• Tanaka Yuki

Classifications

• H10P72/0604

  Process monitoring, e.g. flow or thickness monitoring · CPC title

• H10P70/20

  Cleaning during device manufacture · CPC title

• H10P52/402

  of semiconductor materials · CPC title

• H10P52/00

  Grinding, lapping or polishing of wafers, substrates or parts of devices · CPC title

• G01N23/223

  by irradiating the sample with X-rays or gamma-rays and by measuring X-ray fluorescence · CPC title