Contoured platen design for plasma immerson ion implantation

• US 6,228,176 B1
• Filed: 06/03/1998
• Issued: 05/08/2001
• Est. Priority Date: 02/11/1998
• Status: Active Grant

• Current Assignee: Silicon Genesis
• Original Assignee: Silicon Genesis
• Inventors: Chu, Paul K., Chan, Chung
• Primary Examiner(s): Mills, Gregory
• Assistant Examiner(s): ALEJANDRO MULERO, LUZ L
• Application Number:
  US09/090,301
• Time in Patent Office: 1,070 Days
• Field of Search: 118/728, 118/723 R, 118/723 E, 118/923 ER, 118/923 MW, 118/923 ME, 118/923 MR, 118/923 MA, 118/923 AN, 118/923 I, 156/345, 204/298.15
• US Class Current: 118/728
• CPC Class Codes: C23C 14/48 Ion implantation
• CPC Class Codes: C23C 14/50 Substrate holders
• CPC Class Codes: C23C 14/564 Means for minimising impurities in the coating chamber such as dust, moisture, residual gases
• CPC Class Codes: H01J 37/32412 Plasma immersion ion implantation
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 21/68757 characterised by a coating or a hardness or a material

Abstract

A plasma treatment system (200) for implantation with a novel susceptor with a cotoured underlying surface (201). The system (200) has a variety of elements such as a chamber in which a plasma is generated in the chamber. The system (200) also has a susceptor disposed in the chamber to support a silicon substrate, which has a surface. The contoured underlying surface deflects impinging ions in a direction away from the substrate surface, thereby reducing a possibility of particulate contamination on the substrate. In a specific embodiment, the chamber has a plurality of substantially planar rf transparent windows (26) on a surface of the chamber. The system (200) also has an rf generator (66) and at least two rf sources in other embodiments.

Claims

1. A plasma treatment system for implantation, said system comprising:

a vacuum chamber in which a plasma is generated in said chamber; and

p1 susceptor having a susceptor face disposed in said chamber to support a substrate comprising a substrate face, said susceptor face being substantially a same surface size as said substrate face, whereupon said susceptor face being substantially covered by said substrate face to thereby reduce exposed regions of said susceptor face, said susceptor comprising a material selected from stainless steel or aluminum, and said susceptor is coated with a silicon bearing material, said silicon bearing material being selected from amorphous silicon, polysilicon, or crystalline silicon.

2. The system of claim 1 wherein said chamber comprises a plurality of substantially planar rf transparent windows on a surface of said chamber.

3. The system of claim 2 further comprising:

an rf generator; and

at least two rf sources, each external to said vacuum chamber and each of said rf source electrically coupled to said rf generator and juxtaposed to a respective one of said plurality of substantially planar rf transparent windows, and operative to generate said plasma in the vacuum chamber, said rf sources being operative to produce a local, substantially uniform plasma proximate said substrate.

4. The system of claim 3 further comprising at least one tuning circuit, each said at least one tuning circuit being electrically connected to one of said at least two rf sources.

5. The system of claim 1 wherein said susceptor comprises an edge defined along said susceptor face and a contoured underlying surface that slopes from said edge to a center region of said susceptor.

6. The system of claim 5 wherein said contoured underlying surface deflects ions away from said susceptor face to prevent a possibility of particulate contamination derived from said deflected ions.

7. The system of claim 1 wherein said substrate is a silicon bearing wafer.

8. The system of claim 1 wherein said system is provided in a cluster tool.

9. The system of claim 1 wherein said system is provided as a stand alone unit.