Method for manufacturing a semiconductor substrate

• US 6,191,007 B1
• Filed: 04/28/1998
• Issued: 02/20/2001
• Est. Priority Date: 04/28/1997
• Status: Expired due to Term

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Sasaya, Takanari, Matsui, Masaki, Sakakibara, Jun, Asai, Akiyoshi, Ohshima, Hisayoshi, Enya, Takeshi, Yamauchi, Shoichi, Onoda, Kunihiro
• Primary Examiner(s): Niebling, John F.
• Assistant Examiner(s): LATTIN, CHRISTOPHER W
• Application Number:
  US09/066,971
• Time in Patent Office: 1,029 Days
• Field of Search: 438/162, 438/406, 438/407, 438/262, 438/455, 438/459, 438/158, 438/155, 438/458
• US Class Current: 438/459
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02667 Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
• CPC Class Codes: H01L 21/76243 using silicon implanted buried insulating layers, e.g. oxide layers, i.e. SIMOX techniques
• CPC Class Codes: H01L 21/76254 with separation/delamination along an ion implanted layer, e.g. Smart-cut, Unibond
• CPC Class Codes: H01L 21/76264 SOI together with lateral isolation, e.g. using local oxidation of silicon, or dielectric or polycristalline material refilled trench or air gap isolation regions, e.g. completely isolated semiconductor islands
• CPC Class Codes: H01L 21/76267 Vertical isolation by silicon implanted buried insulating layers, e.g. oxide layers, i.e. SIMOX techniques
• CPC Class Codes: H01L 21/76275 Vertical isolation by bonding techniques
• CPC Class Codes: H01L 21/76281 Lateral isolation by selective oxidation of silicon
• CPC Class Codes: H01L 21/76283 Lateral isolation by refilling of trenches with dielectric material
• CPC Class Codes: H01L 21/84 the substrate being other than a semiconductor body, e.g. being an insulating body
• CPC Class Codes: H01L 2221/68363 used in a transfer process involving transfer directly from an origin substrate to a target substrate without use of an intermediate handle substrate

Abstract

Methods for manufacturing semiconductor substrates in which a semiconductor layer for forming semiconductor device therein is formed on a supporting substrate with an insulating film interposed between, with which in forming the semiconductor layer on a substrate on which a buried pattern structure has been formed it is possible to greatly increase the film thickness uniformity of the semiconductor layer and the film thickness controllability, particularly when the semiconductor layer is being formed as an extremely thin film. As a result, it is possible to achieve improved quality and characteristics of the semiconductor substrates and make possible the deployment of such semiconductor substrates to various uses.

Claims

1. A method for manufacturing a semiconductor substrate comprising:

forming a pattern structure formed by pattern members on a supporting substrate in such a state that it is insulated from the supporting substrate, and making its surface flat;

forming an ion-implanted layer in a substrate for forming a monocrystalline semiconductor layer;

laminating the supporting substrate on which the pattern structure has been formed to the substrate in which the ion-implanted layer has been formed;

detaching the substrate from the supporting substrate at an ion-implanted layer part by carrying out heat treatment on the substrate and the supporting substrate laminated in during said laminating, whereby the monocrystalline semiconductor layer is transferred to the supporting substrate; and

carrying out surface treatment of a detachment face of the semiconductor layer.

2. A method for manufacturing a semiconductor substrate according to claim 1, wherein the pattern structure is used as a buried electrode pattern and said forming a pattern structure comprises:

forming a buried electrode pattern by a material for a buried electrode being selectively disposed in an insulating film formed on the supporting substrate; and

flattening a surface of the supporting substrate on which the buried electrode pattern has been formed.

3. A method for manufacturing a semiconductor substrate according to claim 2, wherein said forming a buried electrode pattern comprises:

forming an oxide film on the supporting substrate;

forming in the oxide film a concavity corresponding to the buried electrode pattern; and

filling the concavity with a buried electrode material.

4. A method for manufacturing a semiconductor substrate according to claim 3, wherein said forming an oxide film includes forming the oxide film by one of thermally oxidizing the supporting substrate and depositing with CVD.

5. A method for manufacturing a semiconductor substrate according to claim 3, wherein said forming in the oxide film a concavity includes forming the concavity by etching the oxide film to a depth corresponding to a shape of the buried electrode pattern.

6. A method for manufacturing a semiconductor substrate according to claim 3, wherein concavity including forming the concavity by removing the oxide film once by etching in correspondence with a shape of the buried electrode pattern and then forming an oxide film over an entire surface of the supporting substrate.

7. A method for manufacturing a semiconductor substrate according to claim 3, wherein said filling the concavity with a buried electrode material comprises:

forming a film of a buried electrode material over an entire surface of the oxide film in which the concavity for the buried electrode pattern has been formed; and

polishing the buried electrode material film so that the buried electrode material remains only in the concavity in the oxide film.

8. A method for manufacturing a semiconductor substrate according to claim 7, wherein said forming a film of a buried electrode material includes forming a polycrystalline silicon film as the buried electrode material film.

9. A method for manufacturing a semiconductor substrate according to claim 8, wherein said forming a film of a buried electrode material includes forming the polycrystalline silicon film doped with an impurity using CVD.

10. A method for manufacturing a semiconductor substrate according to claim 7, including selecting a film of metal material from tungsten, copper and aluminum as the buried electrode material film.

11. A method for manufacturing a semiconductor substrate according to claim 2, wherein said flattening a surface of the supporting substrate comprises:

forming a fattening process film on the supporting substrate on which the pattern structure has been formed; and

flattening a surface of the flattening process film by polishing.

12. A method for manufacturing a semiconductor substrate according to claim 11, wherein said forming a flattening process film includes forming polycrystalline silicon as the flattening process film, and carrying out thermal oxidation after said polishing so that a flattened polycrystalline silicon film is thermally oxidized and thereby made a silicon oxide film.

13. A method for manufacturing a semiconductor substrate according to claim 11, wherein said forming a flattening process film includes forming a film having thermal fluidity, which is selected from BPSG, PSG, and SOG, as the flattening process film.

14. A method for manufacturing a semiconductor substrate according to claim 2, wherein said flattening a surface of the supporting substrate comprises:

forming a polycrystalline silicon film having insulativity on the supporting substrate on which the pattern structure has been formed;

flattening a surface of the polycrystalline silicon film by polishing; and

thermally oxidizing a surface portion of the polycrystalline silicon film so that a surface portion thereof is made into an oxide film but a part in a polycrystalline silicon film state remains therebelow.

15. A method for manufacturing a semiconductor substrate according to claim 1, wherein said forming a pattern structure comprises:

forming an oxide film on the supporting substrate;

forming in the oxide film a concavity corresponding to the buried electrode pattern;

forming a polycrystalline silicon film serving as a buried electrode material on an entire surface of the oxide film in which the concavity has been formed;

polishing the polycrystalline silicon film to a thickness such that a film thickness thereof from the surface of the oxide film remains; and

thermally oxidizing a surface layer portion of the polycrystalline silicon film so that a buried electrode pattern including a polycrystalline silicon film is formed in the concavity.

16. A method for manufacturing a semiconductor substrate according to claim 15, including forming the polycrystalline silicon film doped with an impurity.

17. A method for manufacturing a semiconductor substrate according to claim 1, wherein said forming a pattern structure comprises:

forming an oxide film on the supporting substrate;

forming a buried electrode pattern on the oxide film;

forming a flattening process film on an entire surface of the buried electrode pattern; and

flattening a surface of the flattening process film by polishing it.

18. A method for manufacturing a semiconductor substrate according to claim 17, wherein said forming a flattening process film includes forming an oxide film as the flattening process film.

19. A method for manufacturing a semiconductor substrate according to claim 1, wherein said detaching includes effecting a first heat treatment in which detachment of the substrate at the ion-implanted layer to forms a semiconductor layer on the supporting substrate by heating in a range of 400°

C. to 600°

C., and effecting a second heat treatment in which the semiconductor layer firmly bonds to the supporting substrate by heating above 1000 C.

20. A method for manufacturing a semiconductor substrate according to claim 1, wherein said carrying out surface treatment includes grinding and polishing the detachment face of the semiconductor layer.

21. A method for manufacturing a semiconductor substrate according to claim 1, including carrying out said heat treatment in an oxygen atmosphere so that a thermal oxidation film is formed on the detachment face of the semiconductor layer, and said carrying out said surface treatment includes removing the thermal oxidation film formed on the detachment face by etching and polishing the detachment face from which the thermal oxidation film has been removed.

25. A method according to claim 1, wherein said forming a pattern structure includes:

forming the pattern structure on an auxiliary substrate;

laminating the auxiliary to the supporting substrate with the pattern structure interposed therebetween;

removing the auxiliary substrate from the supporting substrate so that the pattern structure remains on the supporting substrate with a surface thereof; and

flattening the surface of the pattern structure.

26. A method according to claim 25, wherein:

said forming a pattern structure further includes implanting ions into the auxiliary substrate through the pattern structure to form an auxiliary ion-implanted layer in the auxiliary substrate, before laminating the auxiliary substrate to the supporting substrate; and

detaching the auxiliary substrate at the auxiliary ion-implanted layer for removal from the supporting substrate.

27. A method according to claim 1, wherein the pattern structure forming step includes:

forming an insulating film on an auxiliary substrate;

forming an electrode pattern in a region on the insulating film, for forming a buried electrode;

depositing an insulating material on the insulating film in such a state that the insulating material covers the electrode pattern and the instating film;

depositing a flattening process material on the insulating material in such a state that the flattening process material covers the insulating material;

flattening a surface of the flattening process material;

laminating the auxiliary substrate to the supporting substrate with the flattening process film interposed therebetween; and

removing the auxiliary substrate from the supporting substrate so that the pattern structure including the insulating film, the electrode pattern, the insulating material, and the flattening process material remains on the supporting substrate.

28. A method according to claim 27, wherein the insulating film is formed by oxidizing a surface portion of the auxiliary substrate.

29. A method according to claim 27, wherein the electrode pattern is formed by one of a polycrystalline semiconductor material doped with an impurity and a refractory metal material.

42. A method according to claim 1, further comprising, after said detaching the substrate from the supporting substrate, carrying out heat treatment at a temperature higher than that of said heat treatment on the substrate increasing the bonding strength of a bonding interface between the pattern structure on the supporting substrate and the semiconductor layer.

43. A method according to claim 42, carrying out the heat treatment for said increasing the bonding strength in an inert gas atmosphere.

44. A method according to claim 1, further comprising, after said detaching the substrate from the supporting substrate, carrying out supplementary heat treatment in an oxidizing atmosphere to form an oxide layer at an interface between the pattern structure on the supporting substrate and the semiconductor layer.

22. A method for manufacturing a semiconductor substrate in which a semiconductor layer is provided on a pattern structure formed on a supporting substrate, the method comprising:

forming a pattern structure on a supporting substrate;

forming an ion-implanted layer in a second substrate for forming a monocrystalline semiconductor layer between a surface of the second substrate and the ion-implanted layer;

laminating the supporting substrate on which the pattern structure has been formed to the second substrate in which the ion-implanted layer has been formed; and

detaching the second substrate from the supporting substrate at an ion-implanted part by heat treating the second substrate and the supporting substrate, thereby forming the monocrystalline semiconductor layer on the pattern structure formed on the supporting substrate.

23. A method for manufacturing a semiconductor substrate according to claim 22, wherein said forming a pattern structure comprises:

forming a buried electrode pattern by selectively disposing buried electrode material in an insulating film formed on the supporting substrate; and

flattening a surface of the supporting substrate at a side on which the buried electrode pattern is formed.

24. A method for manufacturing a semiconductor substrate according to claim 23, wherein the insulating film is an oxide film formed by one of thermally oxidizing the supporting substrate and depositing with CVD.

48. A method for manufacturing a semiconductor substrate according to claim 22, wherein the ion-implanted layer is formed in the second substrate by carrying out ion-implantation through an insulating layer disposed on the substrate.

49. A method for manufacturing a semiconductor substrate according to claim 48, wherein the insulating layer is an oxide layer.

50. A method for manufacturing a semiconductor substrate according to claim 48, wherein the insulating layer is removed from the second substrate before the supporting substrate is laminated to the second substrate.

30. A method for manufacturing a semiconductor substrate comprising:

forming a pattern structure formed by pattern members on a supporting substrate in such a state that it is insulated from the supporting substrate, and making its surface flat, said pattern forming comprising forming an insulating film on an auxiliary substrate;

forming an electrode pattern in a predetermined region on the insulating film, for forming a buried electrode;

depositing an insulating material on the insulating film in such a state that the insulating material covers the electrode pattern and the insulating film;

depositing a polycrystalline silicon flattening process material on the insulating material in such a state that the flattening process material covers the insulating material;

flattening a surface of the flattening process material;

laminating the auxiliary substrate to the supporting substrate with the flattening process film interposed therebetween; and

removing the auxiliary substrate from the supporting substrate so that the pattern structure including the insulating film, the electrode pattern, the insulating material, and the flattening process material remains on the supporting substrate;

forming an ion-implanted layer in a substrate for forming a monocrystalline semiconductor layer;

laminating the supporting substrate on which the pattern structure has been formed to the substrate in which the ion-implanted layer has been formed;

detaching the substrate from the supporting substrate at an ion-implanted layer part by carrying out heat treatment on the substrate and the supporting substrate laminated in during said laminating, whereby the monocrystalline semiconductor layer is transferred to the supporting substrate; and

carrying out surface treatment of a detachment face of the semiconductor layer.

31. A method for manufacturing a semiconductor substrate comprising:

forming a pattern structure formed by pattern members on a supporting substrate in such a state that it is insulated from the supporting substrate, and making its surface flat, said pattern forming comprising forming an insulating film on an auxiliary substrate;

forming an electrode pattern in a predetermined region on the insulating film, for forming a buried electrode;

depositing an insulating material on the insulating film in such a state that the insulating material covers the electrode pattern and the insulating film;

depositing a flattening process material on the insulating material in such a state that the flattening process material covers the insulating material;

flattening a surface of the flattening process material;

forming an auxiliary ion-implanted layer in the auxiliary substrate;

laminating the auxiliary substrate to the supporting substrate with the flattening process film interposed therebetween; and

removing the auxiliary substrate from the supporting substrate so that the pattern structure including the insulating film, the electrode pattern, the insulating material, and the flattening process material remains on the supporting substrate, said removing of the auxiliary substrate comprising;

performing heat treatment on the auxiliary substrate and the supporting substrate laminated with each other, thereby detaching the auxiliary substrate from the supporting substrate at the auxiliary ion-implanted layer; and

removing a part of the auxiliary substrate remaining on the supporting substrate so that a surface of the insulating film is exposed;

forming an ion-implanted layer in a substrate for forming a monocrystalline semiconductor layer;

laminating the supporting substrate on which the pattern structure has been formed to the substrate in which the ion-implanted layer has been formed;

detaching the substrate from the supporting substrate at an ion-implanted layer part by carrying out heat treatment on the substrate and the supporting substrate laminated in during said laminating, whereby the monocrystalline semiconductor layer is transferred to the supporting substrate; and

carrying out surface treatment of a detachment face of the semiconductor layer.

32. A method according to claim 31, wherein the auxiliary substrate is detached from the supporting substrate at a defective layer part formed in the auxiliary ion-implanted layer.

33. A method according to claim 31, wherein:

the auxiliary ion-implanted layer is formed by implanting ions through the flattening process material; and

the surface of the flattening process material is flattened after forming the auxiliary ion-implanted layer.

34. A method according to claim 31, wherein the surface of the flattening process material is flattened before and after forming the auxiliary ion-implanted layer in the auxiliary substrate.

35. A method according to claim 31, further comprising forming a contamination protection film on the flattening process material after flattening the surface of the flattening process material,

wherein the auxiliary ion-implanted layer is formed after forming the contamination protection film.

36. A method according to claim 31, wherein the part of the auxiliary substrate remaining on the supporting substrate is removed by selecting polishing with the insulating film functioning as a stopper.

37. A method according to claim 31, wherein the part of the auxiliary substrate remaining on the supporting substrate is removed by selective etching with the insulating film functioning as a stopper.

38. A method according to claim 37, wherein the part of the auxiliary substrate is removed by wet-etching using one of aqueous tetra methyl ammonium hydroxide, aqueous sodium hydroxide, and aqueous potassium hydroxide.

45. A method for manufacturing a semiconductor substrate according to claim 38, wherein the ion-implanted layer is formed in the substrate by carrying out ion-implantation through an insulating layer disposed on the substrate.

46. A method for manufacturing a semiconductor substrate according to claim 45, wherein the insulating layer is an oxide layer.

47. A method for manufacturing a semiconductor substrate according to claim 45, wherein the insulating layer is removed from the substrate before the supporting substrate is laminated to the substrate.

39. A method for manufacturing a semiconductor substrate comprising:

forming a pattern structure formed by pattern members on a supporting substrate in such a state that it is insulated from the supporting substrate, and making its surface flat, said pattern forming comprising forming an insulating film on an auxiliary substrate;

forming an electrode pattern in a predetermined region on the insulating film, for forming a buried electrode;

depositing a insulating material on the insulating film in such a state that the insulating material covers the electrode pattern and the insulating film;

depositing a polycrystalline silicon flattening process material on the insulating material in such a state that the flattening process material covers the insulating material;

flattening a surface of the flattening process material;

laminating the auxiliary substrate to the supporting substrate with the flattening process film interposed therebetween; and

removing the auxiliary substrate from the supporting substrate so that the pattern structure including the insulating film, the electrode pattern, the insulating material, and the flattening process material remains on the supporting substrate, said removing of the auxiliary substrate comprising;

grinding an upper portion of the auxiliary substrate; and

selectively polishing the auxiliary substrate until a surface of the insulating film is exposed;

forming an ion-implanted layer in a substrate for forming a monocrystalline semiconductor layer;

laminating the supporting substrate on which the pattern structure has been formed to the substrate in which the ion-implanted layer has been formed;

detaching the substrate from the supporting substrate at an ion-implanted layer part by carrying out heat treatment on the substrate and the supporting substrate laminated in during said laminating, whereby the monocrystalline semiconductor layer is transferred to the supporting substrate; and

carrying out surface treatment of a detachment face of the semiconductor layer.

40. A method for manufacturing a semiconductor substrate comprising:

forming a pattern structure formed by pattern members on a supporting substrate in such a state that it is insulated from the supporting substrate, and making its surface flat, said pattern forming comprising forming an insulating film on an auxiliary substrate;

forming an electrode pattern in a predetermined region on the insulating film, for forming a buried electrode;

depositing a insulating material on the insulating film in such a state that the insulating material covers the electrode pattern and the insulating film;

depositing a polycrystalline silicon flattening process material on the insulating material in such a state that the flattening process material covers the insulating material;

flattening a surface of the flattening process material;

laminating the auxiliary substrate to the supporting substrate with the flattening process film interposed therebetween; and

removing the auxiliary substrate from the supporting substrate so that the pattern structure including the insulating film, the electrode pattern, the insulating material, and the flattening process material remains on the supporting substrate, said removing of the auxiliary substrate comprising;

grinding an upper portion of the auxiliary substrate; and

etching the auxiliary substrate until a surface of the insulating film is exposed;

forming an ion-implanted layer in a substrate for forming a monocrystalline semiconductor layer;

laminating the supporting substrate on which the pattern structure has been formed to the substrate in which the ion-implanted layer has been formed;

detaching the substrate from the supporting substrate at an ion-implanted layer part by carrying out heat treatment on the substrate and the supporting substrate laminated in during said laminating, whereby the monocrystalline semiconductor layer is transferred to the supporting substrate; and

carrying out surface treatment of a detachment face of the semiconductor layer.

41. A method according to claim 40, wherein the auxiliary substrate is wet-etched using one of aqueous tetra methyl ammonium hydroxide, aqueous sodium hydroxide, and aqueous potassium hydroxide until the surface of the insulating film is exposed.