Method and apparatus for beam deflection in a gas cluster ion beam system

• US 9,540,725 B2
• Filed: 04/24/2015
• Issued: 01/10/2017
• Est. Priority Date: 05/14/2014
• Status: Active Grant

• Current Assignee: TEL Manufacturing and Engineering of America, Inc.
• Original Assignee: TEL Epion Inc. (Tokyo Electron Limited)
• Inventors: Regan, Kenneth, Shao, Yan, Becker, Robert K., Olsen, Christopher K.
• Primary Examiner(s): Graybill, David E
• Application Number:
  US14/696,063
• Publication Number:
  US 20150332924A1
• Time in Patent Office: 627 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: C23C 14/10 Glass or silica
• CPC Class Codes: C23C 14/221 Ion beam deposition C23C14/46, C23C14/48 take precedence
• CPC Class Codes: H01J 2237/0812 Ionized cluster beam [ICB] sources
• CPC Class Codes: H01J 37/08 Ion sources; Ion guns
• CPC Class Codes: H01J 37/1477 electrostatic
• CPC Class Codes: H01J 37/317 for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation H01J37/36 takes precedence
• CPC Class Codes: H01J 37/3171 for ion implantation plasma immersion ion implantation H01J37/32412
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/2633 for etching, e.g. sputteretching
• CPC Class Codes: H01L 21/26566 of a cluster, e.g. using a gas cluster ion beam
• CPC Class Codes: H01L 21/28556 by chemical means, e.g. CVD, LPCVD, PECVD, laser CVD H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence

Abstract

Provided is a method of controlling a gas cluster ion beam (GCIB) system for processing structures on a substrate. A GCIB system comprises deflection plates for directing a GCIB towards a substrate, the GCIB system coupled to a substrate scanning device configured to move a substrate in three dimensions. The substrate is exposed to the GCIB while the substrate is being moved by the substrate scanning device. A controller is used to control a set of deflection operating parameters comprising a deflection angle φ, voltage differential of the deflection plates, frequency of the deflection plate power, beam current, substrate distance, pressure in the nozzle, gas flow rate in the process chamber, separation of beam burns, duration of the bean burn, and/or duty cycle of the beam deflector output.

Claims

1. A method of controlling a gas cluster ion beam (GCIB) system for processing a structure on a substrate, the method comprising:

providing a GCIB system comprising deflection plates that direct a GCIB towards a substrate and a deflection circuit;

providing a substrate scanning device configured to move the substrate in three dimensions;

coupling the substrate with the substrate scanning device configured such that a substrate distance between the deflection plates and a surface of the substrate stay within a target range;

exposing the substrate to the GCIB while the substrate is being moved by the substrate scanning device in one or more dimensions;

controlling, using a controller, a deflection angle φ

of the GCIB incident upon the substrate by controlling a set of deflection operating parameters while the substrate is being exposed to the GCIB in order to achieve one or more deflection objectives.

2. The method of claim 1 wherein the one or more deflection objectives include one or more of a target width, a height, a sidewall angle of the structure on the substrate, a percentage of removal of material or layer on the substrate, or a percentage completion of a process operation.

3. The method of claim 2 wherein the set of deflection operating parameters comprises one or more of a voltage differential of the deflection plates, a frequency of a deflection plate power, a beam current, a substrate distance d, a pressure in a nozzle, a gas flow rate in a process chamber, a separation of beam burns, a duration of a beam burn, and/or a duty cycle of a beam deflector output.

4. The method of claim 1 wherein the deflection angle φ

of the GCIB is controlled in a range from 0 to 30 degrees.

5. The method of claim 3, wherein controlling the set of deflection operating parameters comprises controlling the voltage differential of the deflection plates to within a range from −

10 kV to 10 kV.

6. The method of claim 3, wherein controlling the set of deflection operating parameters comprises controlling the frequency of the deflection plate power to within a range from 0 to 1,000 Hz.

7. The method of claim 3, wherein controlling the set of deflection operating parameters comprises controlling the separation of beam burns to within a range from 0 to 100 mm.

8. The method of claim 3, wherein controlling the set of deflection operating parameters comprises controlling the substrate distance d, from the deflection plates to within a range from 4 to 8 cm.

9. The method of claim 3, wherein controlling the set of deflection operating parameters comprises controlling the voltage differential of the deflection plates to within a range from −

10 kV to 10 kV, or from 30 to 60 kV, the separation of beam burns to within a range from 0 to 100 mm, and/or the substrate distance d to within a range from 4 to 8 cm to control the deflection angle φ

to a range from 0 to 30 degrees.

10. The method of claim 9, wherein controlling the set of deflection operating parameters comprises controlling the nozzle pressure to within a range from 100 to 300 psi, the gas flow rate to within a range from 400 to 900 sccm, the beam current to within a range from 50 to 250 μ

A and/or the gas flow rate of one or more of nitrogen (N₂), argon (Ar), 6% chlorine/nitrogen (Cl₂/N₂), 20% triflouromethane (CHF₃), helium (He₂), nitrogen triflouride (NF₃), and/or silicon tetraflouride (SiF₄).

11. The method of claim 10, wherein controlling the set of deflection operating parameters comprises controlling the duration of the beam burn of the GCIB to within a range from 2 to 20 seconds and the duty cycle of the beam deflector output to within a range from 10/80% to 50/50%.

12. The method of claim 3 wherein the GCIB system is configured to modify or grow or dope a layer on the substrate.

13. The method of claim 3 wherein the GCIB system is configured to deposit a layer on the substrate.

14. The method of claim 3 wherein the GCIB system is configured to etch or clean a layer on the substrate.

15. The method of claim 3 wherein the GCIB system is configured to perform modifying, depositing, growing, or doping of a layer in the substrate wherein the substrate is a wafer, a flat panel display (FPD), or a liquid crystal display (LCD).

16. The method of claim 3 wherein the GCIB system comprises a first chamber wherein a gas cluster beam can be formed, a second chamber wherein the gas cluster beam is ionized and accelerated, and a third chamber wherein an accelerated GCIB is utilized to treat the substrate, and/or

wherein one or more individual cluster beams injected by nozzles are used to generate a single gas cluster beam.

17. The method of claim 14 wherein constituent gas clusters in gas cluster beams are ionized by one or more ionizers, the ionizer comprising an electron impact ionizer that produces electrons from one or more filaments.

18. The method of claim 15, wherein the GCIB has a GCIB intensity, and:

wherein the GCIB intensity is modulated by varying a lens focus by changing a first and/or a second lens voltage or mechanically blocking a portion of the GCIB with a variable beam block, adjustable shutter, or variable aperture,

wherein the GCIB intensity is modulated by varying the gas flow from a GCIB source supply, and/or

wherein the GCIB intensity is modulated by either varying a filament voltage or varying an anode voltage.

19. The method of claim 15 wherein a GCIB dose received for a given area of the substrate is changed by adjusting a scan velocity in order to achieve a beam dwell time to treat different regions of the substrate.

20. The method of claim 7, wherein controlling the set of deflection operating parameters further comprises:

controlling a high voltage bipolar power supply configured to rapidly switch outputs that could be modulated slowly with an arbitrary or adjustable midpoint reference and can use alternating current, direct current or a combination of alternating current and direct current.