Apparatus and method for in-situ cleaning in ion beam apparatus

Patent metadata

Field	Value
Publication number	US-9761410-B2
Application number	US-201615012245-A
Country	US
Kind code	B2
Filing date	Feb 1, 2016
Priority date	Feb 1, 2016
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

An apparatus may include an electrostatic filter having a plurality of electrodes; a voltage supply assembly coupled to the plurality of electrodes; a cleaning ion source disposed between the electrostatic filter and a substrate position, the cleaning ion source generating a plasma during a cleaning mode, wherein a dose of ions exit the cleaning ion source; and a controller having a first component to generate a control signal for controlling the voltage supply assembly, wherein a negative voltage is applied to at least one of the plurality of electrodes when the plasma is generated.

First claim

The invention claimed is:

1. An apparatus, comprising:
an electrostatic filter having a plurality of electrodes;
a voltage supply assembly coupled to the plurality of electrodes;
a cleaning ion source disposed between the electrostatic filter and a substrate position, the cleaning ion source generating a plasma during a cleaning mode, wherein a dose of ions exit the cleaning ion source; and
a controller having a first component to generate a control signal for controlling the voltage supply assembly, wherein a negative voltage is applied to at least one of the plurality of electrodes when the plasma is generated.

2. The apparatus of claim 1 , the control signal generating a time a time-varying negative voltage on at least two electrodes of the plurality of electrodes.

3. The apparatus of claim 2 , the control signal generating a DC voltage indexed between the at least two electrodes, wherein a negative voltage is alternately applied between different electrodes.

4. The apparatus of claim 2 , the first component generating a phase shifted alternating current (AC) voltage at the at least two electrodes.

5. The apparatus of claim 1 , further comprising a gas source coupled to the cleaning ion source, the gas source providing chemically active gas to the cleaning ion source, wherein chemically active ions impinge upon the plurality of electrodes.

6. The apparatus of claim 1 , further comprising a gas assembly coupled to the cleaning ion source, the gas assembly providing a mixture of gases to the cleaning ion source, wherein a plurality of ion species are impinge upon the plurality of electrodes.

7. The apparatus of claim 1 , wherein the voltage supply assembly comprises a plurality of voltage sources independently coupled to the plurality of electrodes, respectively.

8. The apparatus of claim 1 , wherein the cleaning ion source is rotatable from a first position directing ions toward the electrostatic filter and a second position directing ions toward the substrate position.

9. The apparatus of claim 1 wherein the cleaning ion source is configured as a plasma flood source.

10. The apparatus of claim 1 , wherein the cleaning ion source comprises an elongated aperture providing the dose of ions.

11. The apparatus of claim 1 , wherein the cleaning ion source comprises a series of holes defining an elongated aperture providing the dose of ions.

12. A system, comprising:
a processing ion source to generate a processing ion beam in a processing mode of operation;
a beamline component disposed downstream of the processing ion source;
a cleaning ion source, separate from the processing ion source and disposed between the beamline component and a substrate position; and
a controller having a first component generate a control signal, wherein a negative voltage is applied to the beamline component with respect to the cleaning ion source when a plasma is generated in the cleaning ion source.

13. The system of claim 12 ,
the beamline component comprising an electrostatic filter having a plurality of electrodes; and
a voltage supply assembly comprising a plurality of voltage sources independently coupled to the plurality of electrodes, respectively; the voltage supply assembly, wherein the control signal controls the voltage supply assembly, and wherein the negative voltage is applied to at least one of the plurality of electrodes when the plasma is generated in the cleaning ion source.

14. A method, comprising:
disposing a cleaning ion source between a substrate position and an electrostatic filter having a plurality of electrodes;
generating a plasma in the cleaning ion source, wherein ions exits an aperture of the cleaning ion source;
coupling a voltage supply assembly to the plurality of electrodes, wherein a plurality of voltage supplies of the voltage supply assembly are connected to the plurality of electrodes, respectively; and
generating a control signal controlling the voltage supply assembly, wherein a negative voltage is applied to at least one of the plurality of electrodes when the plasma is generated in the cleaning ion source.

15. The method of claim 14 , the controlling the voltage supply assembly comprising generating a time-varying negative voltage on at least two electrodes of the plurality of electrodes.

16. The method of claim 15 , the controlling the voltage supply assembly comprising generating a DC voltage indexed between the at least two electrodes, wherein a negative voltage is alternately applied between the at least two electrodes.

17. The method of claim 15 , the controlling the voltage supply assembly comprising generating a phase shifted alternating current (AC) voltage at the at least two electrodes.

18. The method of claim 17 , wherein a phase offset between adjacent electrodes of the plurality of electrodes is 360/n, where n equals a total number of the plurality of electrodes.

19. The method of claim 17 , wherein a frequency of the AC voltage is 100 Hz to 100 kHz.

20. The method of claim 14 , wherein the negative voltage comprises a magnitude of at least 500 V.

Assignees

• Varian Semiconductor Equipment Ass Inc

Inventors

• Likhanskii Alexandre
• Scheuer Jay T
• Lee William Davis

Classifications

• H01J37/3171

  for ion implantation · CPC title

• H01J37/3007 Primary

  Electron or ion-optical systems · CPC title

• H01J2237/057

  Energy or mass filtering · CPC title

• H01J2237/022

  Avoiding or removing foreign or contaminating particles, debris or deposits on sample or tube · CPC title