KR-102960784-B1 - Ion source gas injection beam forming

Abstract

An ion source for extracting a ribbon ion beam having improved height uniformity is disclosed. Gas nozzles are positioned in a chamber near the extraction aperture. The gas introduced near the extraction aperture serves to shape the ribbon ion beam while it is being extracted. For example, the height of the ribbon ion beam can be reduced by injecting gas above and below the ion beam to compress the extracted ion beam in the height direction. In some embodiments, the supply gas is introduced near the extraction aperture. In other embodiments, a shielding gas, such as an inert gas, is introduced near the extraction aperture.

Inventors

• 맥래플린, 아담 엠.

Assignees

• 어플라이드 머티어리얼스, 인코포레이티드

Dates

Publication Date

20260507

Application Date

20221005

Priority Date

20211028

Claims (20)

1. As an ion source, A chamber comprising a first end, a second end, and a plurality of walls connecting the first end and the second end—one of the plurality of walls being an extraction plate having an extraction aperture, and the extraction aperture having a width greater than its height—; A plasma generator for generating plasma within the above chamber; Gas inlet communicating with gas channels; A supply channel communicating with the gas inlet to supply supply gas to the chamber; and Gas nozzles disposed in the chamber near the extraction aperture, communicating with the gas channels to provide a flow of supply gas near the extraction aperture to shape an ion beam extracted from the ion source. An ion source containing
2. In paragraph 1, The plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and the gas channels are ion sources disposed in the side walls.
3. In paragraph 1, An ion source, wherein the plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and the gas channels include tubes disposed in close proximity to the inner or outer surface of the side walls.
4. In paragraph 1, An ion source further comprising plate gas channels disposed on the extraction plate and communicating with the gas channels, wherein the gas nozzles are disposed on the inner surface of the extraction plate in proximity to the extraction aperture.
5. In paragraph 1, The plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and the gas nozzles are disposed on the inner surfaces of the side walls in close proximity to the extraction plate, an ion source.
6. In paragraph 1, The extraction plate comprises a faceplate and an extraction liner disposed between the interior of the chamber and the faceplate, the extraction liner is formed such that a gap exists between the extraction liner and the faceplate, the gap communicates with the gas channels, further comprises plate gas channels disposed in the extraction liner and communicating with the gap, and the gas nozzles are disposed on the surface of the extraction liner in proximity to the extraction aperture, an ion source.
7. In paragraph 1, An ion source in which the dimensions of the gas nozzles vary along the width of the extraction aperture to achieve improved height uniformity of the extracted ribbon ion beam.
8. In paragraph 1, The above plasma generator is an ion source including a heat-dissipating cathode (IHC).
9. As an ion implantation system, The ion source of claim 1; Mass spectrometer; and Platton An ion implantation system including
10. As an ion source, A chamber comprising a first end, a second end, and a plurality of walls connecting the first end and the second end—one of the plurality of walls being an extraction plate having an extraction aperture, and the extraction aperture having a width greater than its height—; A plasma generator for generating plasma within the above chamber; Gas inlet communicating with gas channels; Gas nozzles disposed within the chamber near the extraction aperture and communicating with the gas channels to shape an ion beam extracted from the ion source; and A second gas inlet communicating with a supply channel to supply gas to the chamber. Includes, The above supply channels and the above gas channels are ion sources that do not fluidly communicate with each other.
11. In Paragraph 10, The plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and the gas channels are ion sources disposed in the side walls.
12. In Paragraph 10, An ion source, wherein the plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and the gas channels include tubes disposed in close proximity to the inner or outer surface of the side walls.
13. In Paragraph 10, An ion source further comprising plate gas channels disposed on the extraction plate and communicating with the gas channels, wherein the gas nozzles are disposed on the inner surface of the extraction plate in proximity to the extraction aperture.
14. In Paragraph 10, The plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and the gas nozzles are disposed on the inner surfaces of the side walls in close proximity to the extraction plate, an ion source.
15. In Paragraph 10, The extraction plate comprises a faceplate and an extraction liner disposed between the interior of the chamber and the faceplate, the extraction liner is formed such that a gap exists between the extraction liner and the faceplate, the gap communicates with the gas channels, further comprises plate gas channels disposed in the extraction liner and communicating with the gap, and the gas nozzles are disposed on the surface of the extraction liner in proximity to the extraction aperture, an ion source.
16. In Paragraph 10, An ion source further comprising a first gas container fluidly communicating with the gas inlet, and a second gas container fluidly communicating with the second gas inlet.
17. In Paragraph 10, An ion source further comprising a gas container fluidly communicating with a first mass flow controller and a second mass flow controller, wherein the first mass flow controller controls the flow rate through the gas inlet, the second mass flow controller controls the flow rate through the second gas inlet, and the flow rates through the gas inlet and the second gas inlet are controlled independently.
18. In Paragraph 10, An ion source in which the dimensions of the gas nozzles vary along the width of the extraction aperture to achieve improved height uniformity of the extracted ribbon ion beam.
19. In Paragraph 10, The above plasma generator is an ion source including a heat-dissipating cathode (IHC).
20. As an ion implantation system, The above ion source of Clause 10; Mass spectrometer; and Platton An ion implantation system including

Description

Ion source gas injection beam forming This application claims priority to U.S. patent application serial number 17/513,245 filed on October 28, 2021, the entire contents of said U.S. patent application are incorporated herein by reference. The embodiments of the present disclosure relate to systems for injecting gas into an ion source to form an extracted ion beam. Semiconductor devices are manufactured using multiple processes, some of which implant ions into the workpiece. Various ion sources can be used to generate ions. One such ion source is an inductive cathode (IHC) ion source. An IHC ion source includes a filament positioned behind a cathode. The cathode can be maintained at a higher voltage than the filament. As current passes through the filament, the filament emits thermionic electrons that are accelerated toward the more positively charged cathode. These thermionic electrons serve to heat the cathode, which in turn causes the cathode to emit electrons into the chamber of the ion source. The cathode is positioned at one end of the chamber. A repeller is typically positioned on the end of the chamber facing the cathode. In certain embodiments, the IHC ion source is configured to extract a ribbon ion beam, and the width of the ribbon ion beam is much greater than the height of the ribbon ion beam. Unfortunately, in many systems, the height of the extracted ion beam is not uniform due to the non-uniformity of plasma density within the ion source. For example, if the plasma density is highest in the middle of the chamber, the height of the ribbon ion beam may be greater near the center of the extraction aperture. Varying ion beam heights can be problematic as they may cause non-uniformity in the implantation capacity. Therefore, in some ion implantation systems, additional components, such as lenses, are used to compensate for this issue. However, these additional components add cost and complexity. Therefore, it would be beneficial to have a system capable of controlling the uniformity of the height of the ribbon ion beam extracted from the ion source. An ion source for extracting a ribbon ion beam having improved height uniformity is disclosed. Gas nozzles are positioned in a chamber near the extraction aperture. The gas introduced near the extraction aperture serves to shape the ribbon ion beam while it is being extracted. For example, the height of the ribbon ion beam can be reduced by injecting gas above and below the ion beam to compress the extracted ion beam in the height direction. In some embodiments, the supply gas is introduced near the extraction aperture. In other embodiments, a shielding gas, such as an inert gas, is introduced near the extraction aperture. According to one embodiment, an ion source is disclosed. The ion source comprises a chamber including a first end, a second end, and a plurality of walls connecting the first end and the second end—one of the plurality of walls is an extraction plate having an extraction aperture, and the extraction aperture has a width greater than its height—; a plasma generator for generating plasma within the chamber; a gas inlet communicating with gas channels; a supply channel communicating with said gas inlet to supply a supply gas to the chamber; and gas nozzles disposed within the chamber near the extraction aperture and communicating with the gas channels to provide a flow of the supply gas near the extraction aperture. In some embodiments, the plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and gas channels are disposed in the side walls. In some embodiments, the plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and gas channels include tubes disposed in proximity to the inner or outer surface of the side walls. In some embodiments, the ion source comprises plate gas channels disposed on the extraction plate and communicating with the gas channels, and gas nozzles are disposed on the inner surface of the extraction plate in proximity to the extraction aperture. In certain embodiments, a plurality of walls include a bottom wall facing the extraction plate and side walls adjacent to the extraction plate, and gas nozzles are disposed on the inner surfaces of the side walls in proximity to the extraction plate. In some embodiments, the extraction plate comprises a faceplate and an extraction liner disposed between the interior of the chamber and the faceplate, and the extraction liner is formed such that a gap exists between the extraction liner and the faceplate, the gap communicates with the gas channels, and further comprises plate gas channels disposed on the extraction liner and communicating with the gap, and gas nozzles are disposed on the surface of the extraction liner in proximity to the extraction aperture. In some embodiments, to achieve improved height uniformity of the extracted ribbon ion bea