SYSTEM, METHOD AND APPARATUS FOR REDUCING PLASMA NOISE ON POWER PATH OF ELECTROSTATIC CHUCK

1 . A vacuum plasma system, comprising:

a table having a table power connector;

a fixture spaced apart from the table for defining a chamber between the table and the fixture;

an electrostatic chuck (ESC) mounted to the table in the chamber, the ESC is adapted to support a workpiece and has an ESC power connector that electrically couples with the table power connector;

a coupling extending between the table and ESC power connectors to provide electrical connection therebetween; and

a shield surrounding the coupling and portions of the table and ESC power connectors to reduce external fields applied to the coupling.

2 . A system according to claim 1 , wherein the shield is a Faraday shield.

3 . A system according to claim 2 , wherein the Faraday shield is a metallic tube supported by the table power connector, and the metallic tube closely receives a table pin extending from the table power connector and an ESC pin extending from the ESC power connector.

4 . A system according to claim 3 , wherein the metallic tube, table pin and ESC pin are formed from a same material.

5 . A system according to claim 1 , wherein the vacuum plasma system is plasma etching system for removing material from the workpiece and the fixture is a radio frequency bias source.

6 . A system according to claim 1 , wherein the vacuum plasma system is a sputtering process system for film deposition on the workpiece and the fixture is a target.

7 . A system according to claim 1 , further comprising an insulative sleeve surrounding the table and ESC power connectors, the coupling and the shield to electrically isolate them from the table.

8 . A system according to claim 7 , wherein the insulative sleeve has an axis and is axially spaced apart from the ESC such that the ceramic sleeve does not contact or seal against the ESC.

9 . A system according to claim 8 , wherein the table power connector is mounted in a feedthrough, and the insulative sleeve rests on the feedthrough and is not biased away from the feedthrough toward the ESC.

10 . A system according to claim 9 , further comprising a seal between the feedthrough and the table, and the coupling reduces stress on the seal.

11 . A system according to claim 7 , wherein the table power connector is mounted in a feedthrough, and the insulative sleeve rests on the feedthrough; and further comprising:

a second spring mounted between the feedthrough and the insulative sleeve for biasing an insulative sleeve upward against the ESC to form a seal therebetween.

12 . A system according to claim 7 , wherein the insulative sleeve extends vertically closer to the ESC than the shield.

13 . A vacuum plasma system, comprising:

a table having a table power connector;

a fixture spaced apart from the table for defining a chamber between the table and the fixture;

an electrostatic chuck (ESC) mounted to the table in the chamber, the ESC is adapted to support a workpiece and has an ESC power connector that electrically couples with the table power connector;

a spring extending between the table and ESC power connectors to provide electrical connection therebetween and define a power path;

a Faraday shield surrounding the spring and portions of the table and ESC power connectors to reduce external fields applied to the spring; and

an insulative sleeve surrounding the table and ESC power connectors, the spring and the Faraday shield to electrically isolate them from the table.

14 . A system according to claim 13 , wherein the Faraday shield is a metallic tube supported by the table power connector, the metallic tube closely receives a table pin extending from the table power connector and an ESC pin extending from the ESC power connector, and the metallic tube, table pin and ESC pin are formed from a same material.

15 . A system according to claim 13 , wherein the vacuum plasma system is plasma etching system for removing material from the workpiece and the fixture is a radio frequency bias source.

16 . A system according to claim 13 , wherein the vacuum plasma system is a sputtering process system for film deposition on the workpiece and the fixture is a target.

17 . A system according to claim 13 , wherein the insulative sleeve has an axis and is axially spaced apart from the ESC such that the ceramic sleeve does not contact or seal against the ESC.

18 . A system according to claim 13 , wherein the table power connector is mounted in a feedthrough, the insulative sleeve rests on the feedthrough and is not biased away from the feedthrough toward the ESC, and further comprising a seal between the feedthrough and the table, and the spring reduces stress on the seal.

19 . A system according to claim 13 , wherein the table power connector is mounted in a feedthrough, and the insulative sleeve rests on the feedthrough; and further comprising:

a second spring mounted between the feedthrough and the insulative sleeve for biasing the insulative sleeve upward against the ESC to form a seal therebetween.

20 . A method of shielding in a vacuum plasma system, comprising:

placing a workpiece on an electrostatic chuck (ESC) in a vacuum chamber having a table;

sending a clamping signal to the ESC through a power path to clamp the workpiece on the ESC;

flowing a gas into the vacuum chamber;

shielding a portion of the power path from external electric fields; and

plasma processing the workpiece.

21 . A method according to claim 20 , wherein shielding comprises providing a Faraday shield around an electrical interface between the table and the ESC.

22 . A method according to claim 20 , further comprising flowing gas from a backside of the ESC to the vacuum chamber, and plasma processing comprises sending a bias power signal to the workpiece to plasma process the workpiece.