System and method for gas-phase sulfur passivation of a semiconductor surface

• US 9,558,931 B2
• Filed: 07/12/2013
• Issued: 01/31/2017
• Est. Priority Date: 07/27/2012
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM IP Holding B.V. (ASM International NV)
• Inventors: Tang, Fu, Givens, Michael Eugene, Xie, Qi, Raisanen, Petri
• Primary Examiner(s): Parker, Kenneth
• Assistant Examiner(s): Fan, Bo
• Application Number:
  US13/941,216
• Publication Number:
  US 20140027884A1
• Time in Patent Office: 1,299 Days
• Field of Search: 257/194, 257/192, 438/162, 438/625, 438/172
• US Class Current: 1/1
• CPC Class Codes: C23C 16/4405 Cleaning of reactor or parts inside the reactor by using reactive gases
• CPC Class Codes: C23C 16/45544 characterized by the apparatus
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02301 in-situ cleaning
• CPC Class Codes: H01L 21/02312 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/306 Chemical or electrical treatment, e.g. electrolytic etching to form insulating layers H01L21/31
• CPC Class Codes: H01L 21/67011 Apparatus for manufacture or treatment processes H01L21/30, H01L21/46; for production or after-treatment of single crystals or homogeneous polycrystalline material C30B35/00
• CPC Class Codes: H01L 23/02 Containers; Seals H01L23/12, H01L23/34, H01L23/48, H01L23/552, H01L23/66 take precedence; for memories G11C
• CPC Class Codes: H01L 23/29 characterised by the material , e.g. carbon interlayer dielectrics H01L23/5329
• CPC Class Codes: H01L 23/293 Organic, e.g. plastic
• CPC Class Codes: H01L 23/3171 the coating being directly applied to the semiconductor body, e.g. passivation layer H01L23/3178 takes precedence
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

Improved methods and systems for passivating a surface of a high-mobility semiconductor and structures and devices formed using the methods are disclosed. The method includes providing a high-mobility semiconductor surface to a chamber of a reactor and exposing the high-mobility semiconductor surface to a gas-phase sulfur precursor to passivate the high-mobility semiconductor surface.

Claims

1. A method of passivating a surface of a semiconductor, the method comprising the steps of:

providing the surface of the semiconductor to a reaction chamber of a reactor;

exposing the surface of the semiconductor to a gas-phase sulfur precursor selected from the group consisting of H₂S, NH₄HS, and organosulfur compounds in the reaction chamber; and

passivating the surface of the semiconductor in the reaction chamber using the gas-phase sulfur precursor to form a passivated semiconductor surface,

wherein a pressure within the reaction chamber during the step of passivating is between 0.5 Torr and 750 Torr.

2. The method of passivating a surface of a semiconductor according to claim 1, wherein a source for the sulfur precursor is selected from the group consisting of organosulfur compounds.

3. The method of passivating a surface of a semiconductor according to claim 1, further comprising the step of depositing dielectric material onto the passivated semiconductor surface.

4. The method of passivating a surface of a semiconductor according to claim 3, wherein the step of depositing dielectric material and the step of exposing the surface of the semiconductor to a gas-phase sulfur-precursor are performed in the same reactor.

5. The method of passivating a surface of a semiconductor according to claim 3, wherein the step of depositing dielectric material and the step of exposing the surface of the semiconductor to a gas-phase precursor are performed in separate reactors.

6. The method of passivating a surface of a semiconductor according to claim 3, wherein the step of depositing dielectric material comprises depositing aluminum oxide.

7. The method of passivating a surface of a semiconductor according to claim 1, wherein the semiconductor is a high-mobility semiconductor selected from the group consisting of germanium and III-V semiconductor materials.

8. The method of passivating a surface of a semiconductor according to claim 1, further comprising the step of cleaning the surface of a semiconductor prior, using an in-situ gas-phase process, prior to the step of exposing the surface of the semiconductor to a gas-phase sulfur precursor.

9. The method of passivating a surface of a semiconductor according to claim 1, wherein the step of exposing the surface comprises exposing the surface of the semiconductor wafer to a plasma process.

10. The method of passivating a surface of a semiconductor according to claim 1, wherein the step of providing the surface of the semiconductor to a reaction chamber of a reactor comprises providing the surface within an atomic layer deposition reactor.

11. The method of passivating a surface of a semiconductor according to claim 1, further comprising the steps of providing a carrier gas and mixing the carrier gas with the gas-phase sulfur precursor.

12. A method of passivating a surface of a semiconductor, the method comprising the steps of:

providing the surface of the semiconductor to a reaction chamber of a reactor;

exposing the surface of the semiconductor to a gas-phase sulfur precursor selected from the group consisting of NH₄HS, H₂S, and organosulfur compounds in the reaction chamber; and

passivating the surface of the semiconductor in the reaction chamber using the gas-phase sulfur precursor to form a passivated semiconductor surface.

14. The method of passivating a surface of a semiconductor according to claim 12, further comprising the step of cleaning the surface of the semiconductor using an in-situ gas-phase process using a cleaning source selected from the group consisting of hydrogen gas and hydrogen plasma prior to the step of exposing the surface of the semiconductor to a gas-phase sulfur precursor.

13. A method of passivating a surface of a semiconductor, the method comprising the steps of:

providing the surface of the semiconductor to a reaction chamber of a reactor;

cleaning the surface of the semiconductor using an in-situ hydrogen gas-phase process,

after the step of cleaning, exposing the surface of the semiconductor to a gas-phase sulfur precursor selected from the group consisting of NH₄HS, H₂S, and organosulfur compounds in the reaction chamber; and

passivating the surface of the semiconductor in the reaction chamber using the gas-phase sulfur precursor to form a passivated semiconductor surface.