Method for producing a semiconductor layer

• US 8,921,979 B2
• Filed: 11/05/2013
• Issued: 12/30/2014
• Est. Priority Date: 06/10/2008
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Schulze, Hans-Joachim, Strack, Helmut, Timme, Hans-Joerg, Winkler, Rainer
• Primary Examiner(s): MULPURI, SAVITRI
• Application Number:
  US14/071,802
• Publication Number:
  US 20140061863A1
• Time in Patent Office: 420 Days
• Field of Search: 257607-612, 257/618
• US Class Current: 257/607
• CPC Class Codes: C30B 25/18 characterised by the substrate
• CPC Class Codes: C30B 29/06 Silicon
• CPC Class Codes: C30B 33/02 Heat treatment C30B33/04, C30B33/06 take precedence
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02529 Silicon carbide
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02543 Phosphides
• CPC Class Codes: H01L 21/02546 Arsenides
• CPC Class Codes: H01L 21/02658 Pretreatments cleaning in general H01L21/02041
• CPC Class Codes: H01L 21/263 with high-energy radiation H01L21/261 takes precedence
• CPC Class Codes: H01L 21/3225 Thermally inducing defects using oxygen present in the silicon body for intrinsic gettering H01L21/3226 takes precedence
• CPC Class Codes: H01L 29/04 characterised by their crystalline structure, e.g. polycrystalline, cubic or particular orientation of crystalline planes characterised by physical imperfections H01L29/30
• CPC Class Codes: H01L 29/0657 characterised by the shape of the body

Abstract

A method for producing a semiconductor layer is disclosed. One embodiment provides for a semiconductor layer on a semiconductor substrate containing oxygen. Crystal defects are produced at least in a near-surface region of the semiconductor substrate. A thermal process is carried out wherein the oxygen is taken up at the crystal defects. The semiconductor layer is deposited epitaxially over the near-surface region of the semiconductor substrate.

Claims

1. A semiconductor comprising:

a semiconductor substrate containing oxygen, the semiconductor substrate having first surface and a second surface opposite to the first surface;

protons implanted in at least a near-surface region adjacent to the first surface of the semiconductor substrate;

crystal defects produced by the protons, the crystal defects locally fixing oxygen in the form of oxygen precipitates within the near-surface region of the semiconductor substrate; and

an epitaxial semiconductor layer directly contacting the first surface of the semiconductor substrate,

wherein a concentration of oxygen precipitates is greater within the near-surface region of the semiconductor substrate than within a region of the semiconductor substrate adjacent to the second surface.

2. The semiconductor of claim 1, wherein the semiconductor substrate is a monocrystalline silicon wafer.

3. The semiconductor of claim 2, wherein the silicon wafer is produced according to the Czochralski method.

4. The semiconductor of claim 1, wherein the radiation dose of the protons is between 1×

10¹³cm<sup>−

2</sup> to 1×

10¹⁵ cm<sup>−

2</sup>.

5. The semiconductor of claim 1, wherein a penetration depth T of the protons into the semiconductor substrate is at least 1 μ

m.

6. The semiconductor of claim 5, wherein the penetration depth T is at least 5 μ

m.

7. The semiconductor of claim 1,

wherein the penetrated region of the semiconductor substrate ends at most 3 μ

m before the second surface.

8. A semiconductor comprising:

a semiconductor substrate containing oxygen, the semiconductor substrate having a first surface and a second surface opposite to the first surface;

protons implanted in at least a near-surface region adjacent to the first surface of the semiconductor substrate;

crystal defects produced by the protons, the crystal defects locally fixing oxygen in the form of oxygen precipitates within the near-surface region of the semiconductor substrate;

an epitaxial semiconductor layer directly contacting the first surface of the semiconductor substrate; and

a power semiconductor formed in the semiconductor layer and semiconductor substrate,

wherein a concentration of oxygen precipitates is greater within the near-surface region of the semiconductor substrate than within a region of the semiconductor substrate adjacent to the second surface.

9. The semiconductor of claim 8, wherein the semiconductor substrate is a monocrystalline silicon wafer.

10. The semiconductor of claim 9, wherein the silicon wafer is produced according to the Czochralski method.

11. The semiconductor of claim 8, wherein the radiation dose of the protons is between 1×

10¹³ cm<sup>−

2</sup> to 1×

10¹⁵ cm<sup>−

2</sup>.

12. The semiconductor of claim 8, wherein a penetration depth T of the protons into the semiconductor substrate is at least 1μ

m.

13. The semiconductor of claim 12, wherein the penetration depth T is at least 5 μ

m.

14. The semiconductor of claim 8,

wherein the penetrated region of the semiconductor substrate ends at most 3 μ

m before the second surface.