Heat treatment jig for semiconductor silicon substrates and method for manufacturing the same

Abstract

A heat treatment jig for semiconductor silicon substrates is configured such that a cristobalitized oxide film is formed in a region where the cristobalitized oxide film is in contact with a silicon substrate backside. When said heat treatment jig is used, generation of a slip can be prevented during heat treatment. In the case where the heat treatment jig is used in combination with a shielding plate, particles are further prevented from adhering to the silicon substrate surface to maintain quality characteristics of the semiconductor silicon substrate at a higher level, and device production yield can largely be improved. The heat treatment jig can easily be manufactured by introducing a cristobalitization promoting agent to a surface or in the vicinity of a surface of the heat treatment jig, performing the heat treatment at temperatures in the range of 1000 to 1380° C., and repeating the introduction of the cristobalitization promoting agent and the heat treatment.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a configuration example of a conventional heat treatment boat for semiconductor silicon substrates used in a vertical heat treatment furnace;

FIG. 2 is a microphotograph illustrating a cross-section of an oxide film formed in a surface of a heat treatment jig according to the present invention;

FIG. 3 is a SEM photograph illustrating a surface of the oxide film formed in the surface of the heat treatment jig according to the present invention;

FIG. 4 is a microphotograph illustrating a cross-section of the oxide film formed in the surface of the conventional heat treatment jig;

FIG. 5A is a longitudinal cross-sectional view of part of the heat treatment boat, schematically showing how a cristobalitized heat treatment jig of a disc structure type is mounted, and FIG. 5B is a cross-sectional view seen in the direction of arrow A-A of FIG. 5A;

FIG. 6A is a longitudinal cross-sectional view of part of the heat treatment boat, schematically showing how a heat treatment jig with a shielding plate comprising the cristobalitized heat treatment jig of the disc structure type and the shielding plate of the disc structure type is mounted, and FIG. 6B is a cross-sectional view seen in the direction of arrow B-B of FIG. 6A;

FIG. 7A is a longitudinal cross-sectional view of part of the heat treatment boat, schematically showing how a heat treatment jig with a shielding plate comprising a cristobalitized heat treatment jig of a ring structure type and the shielding plate of a disc structure type is set, and FIG. 7B is a cross-sectional view seen in the direction of arrow C-C of FIG. 7A;

FIG. 8 is a longitudinal cross-sectional view of part of the heat treatment boat, schematically showing how a heat treatment jig with a shielding plate is set;

FIG. 9 is a longitudinal cross-sectional view of part of the heat treatment boat, schematically showing a more preferable example of how the heat treatment jig with a shielding plate is set; and

FIG. 10A is a longitudinal cross-sectional view of part of the heat treatment boat, schematically showing another more preferable example of how the heat treatment jig with a shielding plate is set, FIG. 10B is a cross-sectional view seen in the direction of arrow D-D of FIG. 10A, and FIG. 10C is a plan view.

Claims

1. A heat treatment jig for semiconductor silicon substrates which is mounted on a heat treatment boat in a vertical heat treatment furnace to support a semiconductor silicon substrate while contacting therewith, wherein a cristobalitized oxide film is formed in a region functioning to support said semiconductor silicon substrates while contacting therewith.

2. The heat treatment jig for semiconductor silicon substrates according to claim 1, wherein the cristobalitized oxide film is obtained by performing heat treatment after a cristobalitization promoting agent is introduced to the heat treatment jig or to a surface or in the vicinity of a surface of the heat treatment jig to which an oxidation treatment is performed beforehand.

3. The heat treatment jig for semiconductor silicon substrates according to claim 1, wherein the cristobalitization promoting agent is an alkali metal, an alkali earth metal, aluminum, or a transition metal.

4. The heat treatment jig for semiconductor silicon substrates according to claim 2, wherein the cristobalitization promoting agent is an alkali metal, an alkali earth metal, aluminum, or a transition metal.

5. The heat treatment jig for semiconductor silicon substrates according to claim 2, wherein a concentration of the cristobalitization promoting agent introduced to the surface or in the vicinity of the surface of the heat treatment jig is not less than 1×1010 atoms/cm2 in area equivalent.

6. The heat treatment jig for semiconductor silicon substrates according to claim 3, wherein a concentration of the cristobalitization promoting agent introduced to the surface or in the vicinity of the surface of the heat treatment jig is not less than 1×1010 atoms/cm2 in area equivalent.

7. The heat treatment jig for semiconductor silicon substrates according to claim 4, wherein a concentration of the cristobalitization promoting agent introduced to the surface or in the vicinity of the surface of the heat treatment jig is not less than 1×1010 atoms/cm2 in area equivalent.

8. A heat treatment jig for semiconductor silicon substrates, comprising: a heat treatment jig as in claim 1; anda shielding plate which prevents particles from adhering to a semiconductor silicon substrate, the shielding plate having a diameter larger than that of the heat treatment jig, the particles being generated due to the cristobalitized oxide film.

9. A method for manufacturing the heat treatment jig for semiconductor silicon substrates in claim 1, comprising the steps of: introducing a cristobalitization promoting agent to a surface or in the vicinity of a surface of the heat treatment jig;performing heat treatment at temperatures in the range of 1000 to 1380° C.; andrepeating the introduction of the cristobalitization promoting agent and the heat treatment.

10. The method for manufacturing the heat treatment jig for semiconductor silicon substrates according to claim 9, wherein impurities mixed in a heat treatment jig cleaning chemical agent are utilized as the cristobalitization promoting agent.

11. The method for manufacturing the heat treatment jig for semiconductor silicon substrates according to claim 10, wherein part of the oxide film existing in the surface of the heat treatment jig is left over when the heat treatment jig is cleaned while hydrofluoric acid is used as the heat treatment jig cleaning chemical agent.

12. A method for manufacturing the heat treatment jig for semiconductor silicon substrates in claim 2, comprising the steps of: introducing a cristobalitization promoting agent to a surface or in the vicinity of a surface of the heat treatment jig;performing heat treatment at temperatures in the range of 1000 to 1380° C.; andrepeating the introduction of the cristobalitization promoting agent and the heat treatment.

13. The method for manufacturing the heat treatment jig for semiconductor silicon substrates according to claim 12, wherein impurities mixed in a heat treatment jig cleaning chemical agent are utilized as the cristobalitization promoting agent.

14. The method for manufacturing the heat treatment jig for semiconductor silicon substrates according to claim 13, wherein part of the oxide film existing in the surface of the heat treatment jig is left over when the heat treatment jig is cleaned while hydrofluoric acid is used as the heat treatment jig cleaning chemical.

15. A method for manufacturing the heat treatment jig for semiconductor silicon substrates in claim 4, comprising the steps of: introducing a cristobalitization promoting agent to a surface or in the vicinity of a surface of the heat treatment jig;performing heat treatment at temperatures in the range of 1000 to 1380° C.; andrepeating the introduction of the cristobalitization promoting agent and the heat treatment.

16. The method for manufacturing the heat treatment jig for semiconductor silicon substrates according to claim 15, wherein impurities mixed in a heat treatment jig cleaning chemical are utilized as the cristobalitization promoting agent.

17. The method for manufacturing the heat treatment jig for semiconductor silicon substrates according to claim 16, wherein part of the oxide film existing in the surface of the heat treatment jig is left over when the heat treatment jig is cleaned while hydrofluoric acid is used as the heat treatment jig cleaning chemical agent.

18. A method for manufacturing the heat treatment jig for semiconductor silicon substrates in claim 7, comprising the steps of: introducing a cristobalitization promoting agent to a surface or in the vicinity of a surface of the heat treatment jig;performing heat treatment at temperatures in the range of 1000 to 1380° C.; andrepeating the introduction of the cristobalitization promoting agent and the heat treatment.

19. The method for manufacturing the heat treatment jig for semiconductor silicon substrates according to claim 18, wherein impurities mixed in a heat treatment jig cleaning chemical are utilized as the cristobalitization promoting agent.

20. The method for manufacturing the heat treatment jig for semiconductor silicon substrates according to claim 19, wherein part of the oxide film existing in the surface of the heat treatment jig is left over when the heat treatment jig is cleaned while hydrofluoric acid is used as the heat treatment jig cleaning chemical.