Apparatus and method for substrate clamping in a plasma chamber

Patent metadata

Field	Value
Publication number	US-9337072-B2
Application number	US-95010510-A
Country	US
Kind code	B2
Filing date	Nov 19, 2010
Priority date	Oct 4, 2006
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

The present invention generally provides methods and apparatus for monitoring and maintaining flatness of a substrate in a plasma reactor. Certain embodiments of the present invention provide a method for processing a substrate comprising positioning the substrate on an electrostatic chuck, applying an RF power between the an electrode in the electrostatic chuck and a counter electrode positioned parallel to the electrostatic chuck, applying a DC bias to the electrode in the electrostatic chuck to clamp the substrate on the electrostatic chuck, and measuring an imaginary impedance of the electrostatic chuck.

First claim

The invention claimed is:

1. A method for monitoring a substrate during a plasma process, comprising:
positioning a substrate on an electrostatic chuck in a process chamber;
applying an RF power between an electrode in the electrostatic chuck and a counter electrode positioned parallel to the electrostatic chuck;
applying a DC bias to the electrode in the electrostatic chuck to clamp the substrate on the electrostatic chuck;
monitoring slope variation of impedance of the electrostatic chuck over a time duration; and
correlating slope variation of the impedance of the electrostatic chuck to a flatness of the substrate.

2. The method of claim 1 , wherein the monitoring variation of impedance of the electrostatic chuck comprises monitoring variation of imaginary impedance of the electrostatic chuck.

3. The method of claim 2 , further comprising adjusting the DC bias applied to the electrode in the electrostatic chuck according to the variation of imaginary impedance of the electrostatic chuck.

4. The method of claim 1 , further comprising correlating an overall negative slope variation of the impedance of the electrostatic chuck to a decrease in the flatness of the substrate.

5. The method of claim 4 , further comprising increasing the DC bias applied to the electrostatic chuck when the slope of the imaginary impedance is negative.

6. The method of claim 1 , wherein the monitoring variation of impedance comprises measuring a voltage and a current of the electrostatic chuck.

7. The method of claim 6 , wherein the voltage and the current are measured using a VI probe connected to the counter electrode.

8. The method of claim 1 , wherein the monitoring variation of impedance of the process chamber is performed without measuring capacitances associated with the process chamber.

9. A method for monitoring a substrate during a plasma process, comprising:
positioning a substrate in a plasma generator having first and second parallel electrodes, wherein the substrate is positioned between the first and second parallel electrodes and substantially parallel to the first and second parallel electrodes;
applying an RF power between the first and second electrodes of the plasma generator;
applying a DC bias to the first parallel electrode to secure the substrate directly or indirectly on the first parallel electrode; and
monitoring flatness of the substrate by determining slope variation of imaginary impedance of the plasma generator over a time duration, wherein a negative slope indicates a decrease in the flatness of the substrate.

10. The method of claim 9 , wherein the imaginary impedance is determined using a sensor connected to one of parallel electrodes of the plasma generator.

11. The method of claim 9 , further comprising adjusting the DC bias to the first parallel electrode according to the slope variation of the imaginary impedance.

12. The method of claim 9 , wherein the determining the slope variation of imaginary impedance of the plasma generator is performed without measuring capacitances associated with the plasma generator.

Assignees

• Balasubramanian Ganesh
• Bansal Amit
• Juco Eller Y
• Ayoub Mohamad
• Kim Hyung-Joon
• Janakiraman Karthik
• Rathi Sudha
• Padhi Deenesh
• Seamons Martin Jay
• Sivaramakrishnan Visweswaren
• Kim Bok Hoen
• Al-Bayati Amir
• Witty Derek R
• M Saad Hichem
• Baryshnikov Anton
• Chan Chiu
• Liu Shuang
• Applied Materials Inc

Inventors

• Balasubramanian Ganesh
• Bansal Amit
• Juco Eller Y
• Ayoub Mohamad
• Kim Hyung-Joon
• Janakiraman Karthik
• Rathi Sudha
• Padhi Deenesh
• Seamons Martin Jay
• Sivaramakrishnan Visweswaren
• Kim Bok Hoen
• Al-Bayati Amir
• Witty Derek R
• M Saad Hichem
• Baryshnikov Anton
• Chan Chiu
• Liu Shuang

Classifications

• H10P72/0604

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

• H10P72/0421

  for drying etching · CPC title

• H10P72/72 Primary

  using electrostatic chucks · CPC title

• H10P72/70 Primary

  for supporting or gripping · CPC title

• H01L21/67253

  Electricity · mapped topic