Method for producing a silicon substrate having modified surface properties and a silicon substrate of said type

• US 20100035068A1
• Filed: 04/27/2007
• Published: 02/11/2010
• Est. Priority Date: 06/23/2006
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Farber, Paul, Illing, Matthias, Schelling, Christoph, Benzel, Hubert, Armbruster, Simon, Laermer, Franz, Kronmueller, Silvia, Feyh, Ando, Reichenbach, Ralf, Lammel, Gerhard
• Granted Patent: US 8,492,850 B2
• Time in Patent Office: Days
• US Class Current: 428/428
• CPC Class Codes: H01L 21/02008 Multistep processes
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02529 Silicon carbide
• CPC Class Codes: H01L 21/02573 Conductivity type
• CPC Class Codes: H01L 21/02601 Nanoparticles fullerenes H10K85/211
• CPC Class Codes: H01L 21/02612 Formation types
• CPC Class Codes: H01L 21/02656 Special treatments
• CPC Class Codes: H01L 21/02658 Pretreatments cleaning in general H01L21/02041
• CPC Class Codes: H01L 21/02667 Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
• CPC Class Codes: H01L 33/346 containing porous silicon

Abstract

A method for producing a silicon substrate, including the steps of providing a silicon substrate having an essentially planar silicon surface, producing a porous silicon surface having a plurality of pores, in particular having macropores and/or mesopores and/or nanopores, applying a filling material that is to be inserted into the silicon, which has a diameter that is less than a diameter of the pores, inserting the filling material into the pores and removing the excess filling material form the silicon surface, if necessary, and tempering the silicon substrate that is furnished with the filling material that has been filled into the pores, at a temperature between ca. 1000° C. and ca. 1400° C., in order to close the generated pores again and to enclose the filling material.

Claims

1-13. -13. (canceled)

14. A method for producing a silicon substrate, the method comprising:

providing a silicon substrate having an essentially planar silicon surface;

producing a porous silicon surface having a plurality of pores, the pores including at least one of macropores, mesopores and nanopores;

applying a filling material which is to be inserted into the silicon, and which has a diameter that is less than a diameter of the pores;

inserting the filling material into the pores;

removing the excess filling material from the silicon surface, if necessary; and

tempering the silicon substrate together with the filling material that has been filled into the pores, at a temperature between ca. 1000°

C. and 1400°

C., so as to close the pores again and to enclose the filling material.

15. The method of claim 14, wherein the insertion of the filling material into the pores takes place by generating vibrations using at least one of ultrasound, mechanical motions of the silicon substrate, supercritical carbon dioxide and from the liquid phase, including suspension or emulsion.

16. The method of claim 14, wherein the pores of the porous silicon surface are produced using electrochemical anodizing.

17. The method of claim 14, wherein the tempering takes place in a hydrogen atmosphere.

18. The method of claim 14, wherein the silicon substrate includes a monocrystalline silicon matrix.

19. The method of claim 14, wherein the filling material to be inserted is inserted in a nanoparticle form.

20. The method of claim 14, wherein the filling material to be inserted is at least one of a carbon and a carbon compound, including a hydrocarbon, a high-molecular aromatic or aliphatic carbon compound, and a nitrogen-carbon compound.

21. The method of claim 14, wherein the filling material to be inserted is a mixture of at least two different materials.

22. The method of claim 14, wherein the pores are generated only in a first, monocrystalline silicon layer of the silicon substrate.

23. The method of claim 14, wherein the filling material to be inserted includes a doping substance for producing one of p-type carbide and n-type silicon carbide.

24. The method of claim 14, wherein a first material is filled into a first region of the silicon substrate formed using pores, and a second material is filled into a second region of the silicon substrate that is generated using pores, which is different from the first filling material.

25. A silicon substrate device, comprising:

a silicon substrate having an essentially planar silicon surface, wherein a porous silicon surface having a plurality of pores, the pores including at least one of macropores, mesopores and nanopores is filled by applying a filling material which is to be inserted into the silicon, and which has a diameter that is less than a diameter of the pores, wherein any excess filling material is removed from the silicon surface;

wherein the silicon substrate has been tempered together with the filling material that has been filled into the pores, at a temperature between ca. 1000°

C. and 1400°

C., so as to close the pores again and to enclose the filling material, and

wherein the filling material is selected from the group of the rare earths and is oxidized after the tempering.

26. A silicon wafer, comprising:

a silicon substrate having an essentially planar silicon surface, wherein a porous silicon surface having a plurality of pores, the pores including at least one of macropores, mesopores and nanopores is filled by applying a filling material which is to be inserted into the silicon, and which has a diameter that is less than a diameter of the pores, wherein any excess filling material is removed from the silicon surface;

wherein the silicon substrate has been tempered together with the filling material that has been filled into the pores, at a temperature between ca. 1000°

C. and 1400°

C., so as to close the pores again and to enclose the filling material, and

wherein the filling material is selected from the group of the rare earths and is oxidized after the tempering.