ACCELERATOR PARTICLE BEAM APPARATUS AND METHOD FOR LOW CONTAMINATE PROCESSING

• US 20090206275A1
• Filed: 10/02/2008
• Published: 08/20/2009
• Est. Priority Date: 10/03/2007
• Status: Abandoned Application

• Current Assignee: Silicon Genesis
• Original Assignee: Silicon Genesis
• Inventors: Lamm, Albert, Henley, Francois J., Brailove, Adam
• Application Number:
  US12/244,687
• Publication Number:
  US 20090206275A1
• Time in Patent Office: Days
• US Class Current: 250/424
• CPC Class Codes: H01J 2237/022 Avoiding or removing foreign or contaminating particles, debris or deposits on sample or tube
• CPC Class Codes: H01J 2237/04735 with electrostatic means
• CPC Class Codes: H01J 2237/057 Energy or mass filtering
• CPC Class Codes: H01J 2237/18 Vacuum control means
• CPC Class Codes: H01J 2237/31705 Impurity or contaminant control
• CPC Class Codes: H01J 37/3171 for ion implantation plasma immersion ion implantation H01J37/32412
• CPC Class Codes: H01L 21/76254 with separation/delamination along an ion implanted layer, e.g. Smart-cut, Unibond

Abstract

A system of introducing a particle beam such as a linear accelerator particle beam for low contaminate processing. The system includes an accelerator apparatus configured to generate a first particle beam including at least a first ionic specie in an energy level of 1 MeV to 5 MeV or greater. Additionally, the system includes a beam filter coupled to the linear accelerator apparatus to receive the first particle beam. The beam filter is in a first chamber and configured to generate a second particle beam with substantially the first ionic specie only. The first chamber is associated with a first pressure. The system further includes an end-station including a second chamber coupled to the first chamber for extracting the second particle beam. The second particle beam is irradiated onto a planar surface of a bulk workpiece loaded in the second chamber for implanting the first ionic specie. The second chamber is associated with a second pressure that is higher than the first pressure. Optional beam scanning can also be added between the beam filter and the end-station.

Claims

1. A system of introducing a linear accelerator particle beam for low contaminate processing, the system comprising:

a particle accelerator including at least an ion source for generating a plurality of charged particles, and an apparatus for accelerating and confining the plurality of charged particles in a first particle beam, the first particle beam being outputted to a first exit aperture in a first spatial direction;

a beam filter apparatus coupled to the first exit aperture to receive the first particle beam, the beam filter apparatus including a first chamber of a first mass-selection device to process the first particle beam and generate a second particle beam, the second particle beam including substantially a first ionic specie and being outputted to a second exit aperture in a second spatial direction different from the first spatial direction;

an end-station including a second chamber coupled to the beam filter apparatus to receive the second particle beam, the second chamber configured to house a workpiece having a planar surface configured to receive the second particle beam for implanting the first ionic specie.

2. The system of claim 1 further comprising an apparatus configured to perform a controlled cleaving of a film of material from the workpiece, the film having a thickness corresponding to a depth of implantation of the particles from the second beam.

3. The system of claim 1 wherein the first chamber is associated with a first pressure and the second chamber is associated with a second pressure, the first pressure being set to be at least 10×

lower relative to the second pressure.

4. The system of claim 3 wherein the second pressure in the second chamber is about (1×

10<sup>−

3</sup>) torr and lower.

5. The system of claim 1 wherein the apparatus for accelerating and confining the plurality of charged particles in a first particle beam is a linear accelerator (linac) system.

6. The system of claim 5 wherein the linac system comprises a stage selected from a radio frequency quadrupole (RFQ) stage, a RF-Focused Interdigitated (RFI) stage, a Drift-Tube Linac (DTL) stage, or a Quadrupole-Focused Interditigated (QFI) stage.

7. The system of claim 1 wherein the apparatus for accelerating and confining the plurality of charged particles in a first particle beam comprises a cyclotron or a DC electrostatic particle accelerator.

8. The system of claim 1 wherein the first particle beam is in an energy level ranging from 0.5 MeV to 5 MeV.

9. The system of claim 1 wherein the first particle beam comprises the first ionic specie and a plurality of contaminate species originated from either the ion source or generated during the propagation through the linear accelerator.

10. The system of claim 9 wherein the plurality of contaminate species is selected from the group of Hydrogen isotope specie, Helium specie, Oxygen specie, Nitrogen specie, Carbon specie, Aluminum Specie, Iron Specie, Copper Specie, and constituent elements of aluminum and steel alloys.

11. The system of claim 1 wherein the mass-selection device comprises a magnetic sector, an electric sector, or any combination of an electric sector, a magnetic sector, electric/magnetic (E×

B), and one or more drift channels.

12. The system of claim 1 wherein the mass-selection device is based on a mechanism for differentiating particles by charge-to-mass ratio.

13. The system of claim 1 wherein the first spatial direction relative to the second spatial direction forms an angle in a horizontal plane or in a vertical plane.

14. The system of claim 13 wherein the angle is about 45 degrees, about 90 degrees, or about 135 degrees.

15. The system of claim 1 wherein the beam filter apparatus is a two-stage mass-selection device further comprising a third chamber housing a second mass-selection device coupled to the first mass-selection device in series to produce the second particle beam.

16. The system of claim 15 wherein the third chamber is associated with a third pressure that is set to be lower relative to the second pressure.

17. The system of claim 1 wherein the end-station is part of a cluster tool configured to integrate with a plurality of chambers including the second chamber.

18. The system of claim 17 wherein the second chamber is configured to couple with one or more load locks for loading in/out the workpiece.

19. The system of claim 1 wherein the workpiece is a thick film on a substrate, a tile workpiece, a wafer workpiece, or a bulk workpiece.

20. The system of claim 19 wherein the bulk workpiece comprises a shaped ingot of single-crystalline or polycrystalline silicon, germanium, III/V group compound semiconductor.

21. The system of claim 20 wherein the plurality of bulk workpieces are loaded on a rack that is movable in a plane allowing the second particle beam effectively scanning over all the planar surfaces of the plurality of bulk workpieces.

23. The system of claim 1 further comprising an apparatus configured to perform a controlled cleaving of a film of material from the workpiece, the film having a thickness corresponding to a depth of implantation of the particles from the second beam.

44. The system of claim 1 further comprising a beam scanner configured to alter over time a location that the second particle beam impinges upon the workpiece.

22. A system of introducing an accelerator particle beam for low contaminate processing, the system comprising:

a particle accelerator apparatus configured to generate a first particle beam;

a beam filter coupled to the linear accelerator apparatus to receive the first particle beam, the beam filter being in a first chamber and configured to generate a second particle beam with substantially a first ionic specie;

an end-station including a second chamber coupled to the first chamber for extracting the second particle beam, the second particle beam being irradiated onto a planar surface of a workpiece loaded in the second chamber for implanting the first ionic specie.

24. The system of claim 22 wherein the first chamber is associated with a first pressure and the second chamber is associated with a second pressure, the first pressure lower relative to the second pressure.

25. The system of claim 24 wherein the second pressure is about 1×

10<sup>−

3</sup> torr and lower.

26. The system of claim 22 wherein the particle accelerator comprises a RF accelerator such as an RF linac or a cyclotron, or comprises a DC electrostatic accelerator.

27. The system of claim 22 wherein the first particle beam is in an energy level ranging from 1 MeV to 5 MeV.

28. The system of claim 22 wherein the first particle beam comprises the first ionic specie and a plurality of contaminate species originated from either the ion source or generated during the propagation through the linear accelerator.

29. The system of claim 22 wherein the plurality of contaminate species is selected from Hydrogen isotope specie, Helium specie, Oxygen specie, Nitrogen specie, Carbon specie, Aluminum specie, Iron specie, Copper specie, elements of aluminum and steel alloys.

30. The system of claim 22 wherein the beam filter comprises a magnetic sector, an electric sector, or any combination of an electric sector, a magnetic sector, electric/magnetic sectors, and one or more drift channels for separating the first ionic specie from the first particle beam.

31. The system of claim 22 wherein the beam filter is based on a mechanism of generating separate trajectories with different radius of curvature for particles with different charge-to-mass ratio.

32. A method of introducing a accelerator particle beam for low contaminate processing, the method comprising:

generating a plurality of ionic particles by an ion source, the plurality of ionic particles comprising multiple species including a first ionic specie;

accelerating and confining the plurality of ionic particles to a first particle beam with energy level of the first specie at least in a range of 0.5 MeV to 5 MeV using a linear accelerator;

extracting the first particle beam into a first chamber;

processing the first particle beam in the first chamber to separate the first ion specie from the multiple species;

extracting a second particle beam into a second chamber, the second particle beam comprising substantially the first ion specie only;

irradiating the second particle beam to implant the first ion specie into one or more planar surfaces of one or more bulk workpieces loaded in the second chamber.

33. The method of claim 32 wherein the accelerating and confining the plurality of ionic particles to a first particle beam comprises:

extracting the plurality of ionic particles from the ion source through a low energy beam transport unit;

accelerating and confining the plurality of ionic particles in a multi-stage radio frequency (RF) quadrupole (RFQ) linear accelerator (linac), a cyclotron, or a DC electrostatic accelerator; and

generating the first particle beam.

34. The method of claim 32 wherein the processing the first particle beam in the first chamber to separate the first ion specie from the multiple species further comprises:

receiving the first particle beam;

guiding the first particle beam into a beam filter;

guiding the first ionic specie through the beam filter while dumping the rest of the multiple species.

35. The method of claim 34 wherein the beam filter comprises a mass-selection device based on a mechanism for differentiating particles by charge-to-mass ratio.

36. The method of claim 35 wherein the charge-to-mass selection device comprises a combination of one or more electric sectors, one or more magnetic sectors, and one or more drift channels.

37. The method of claim 32 wherein the extracting a second particle beam into a second chamber comprises:

receiving a plurality of first ionic specie particles to form a second particle beam;

outputting the second particle beam through a high-energy beam transport unit at a second exit aperture of the first chamber, the second exit aperture being connected to the second chamber;

expanding optionally the second particle beam to obtain a desired beam diameter.

38. The method of claim 32 wherein the irradiating the second particle beam to implant the first ion specie into one or more planar surfaces comprises:

directing the second particle beam to a spot of the one or more planar surfaces in substantially perpendicular direction;

scanning the second particle beam to move the spot over the entire one or more planar surfaces;

controlling a dosage by adjusting at least a beam current, a beam diameter, and a scanning speed.

39. The method of claim 32 wherein the one or more bulk workpieces can be ingots of single-crystalline or polycrystalline silicon, germanium, III/V group compound semiconductor, or silicon carbide (SiC).

40. The method of claim 32 wherein the second chamber belongs to a cluster tool configured to perform other processes including surface re-polishing, post-processing, and controlled cleaving or direct film transferring.

41. The method of claim 32 wherein the first chamber is associated with a first pressure and a second chamber is associated with a second pressure.

42. The method of claim 41 wherein the second pressure is about 1×

10<sup>−

3</sup> torr or lower.

43. The method of claim 42 wherein the first pressure is one or two orders of magnitude lower than the second pressure.

45. The method of claim 32 further comprising translating the bulk workpieces along at least one axis during impingement of the second particle beam.

46. An apparatus comprising:

a linear accelerator having an inlet in vacuum communication with an ion source and an outlet in vacuum communication with an inlet of a beam filter;

an end station in vacuum communication with an outlet of the beam filter and configured to support a target workpiece;

a host computer comprising,

a processor in electronic communication with at least one element selected from the ion source, the linear accelerator, the beam filter, and the end station, and

a computer readable storage medium in electronic communication with the processor and having stored thereon code configured to instruct the processor to,

cause the ion source to generate a plurality of ionic particles comprising multiple species including a first ionic specie,

cause the linear accelerator to accelerate the plurality of ionic particles to a particle beam with energy level of the first specie at least in a range of 0.5 MeV to 5 MeV,

cause the beam filter to process the particle beam in the first chamber to separate the first ion specie from the multiple species, and

irradiate the particle beam to implant the first ion specie into one or more planar surfaces of one or more workpieces loaded in the end station.

47. The apparatus of claim 46 wherein the computer readable storage medium further comprises code to instruct scanning of the first ion species over the surface of the workpiece during the irradiation.

48. The apparatus of claim 46 wherein the computer readable storage medium further comprises code to instruct translation of the workpiece along one or more axes during the irradiation.

49. The apparatus of claim 46 wherein:

the beam filter comprises a first chamber magnetic communication with an analyzing magnet; and

the computer readable storage medium further comprises code to instruct the analyzing magnet to apply a magnetic field to the first chamber.

50. The apparatus of claim 46 wherein the computer readable storage medium further comprises code to instruct that the first chamber to be maintained at a first pressure lower than a second pressure of the end station.

51. A method of forming a thin film, the method comprising:

generating a high energy particle beam;

passing the high energy particle beam through a filter to remove unwanted contamination from the particle beam;

directing the decontaminated particle beam at a surface of a substrate;

forming a cleave region in the substrate from particles implanted from the beam; and

performing a controlled cleaving in the cleave region to remove a thin film of material from the substrate.

52. The method of claim 51 wherein a thickness of the thin film is at least about 10 μ

m.