Unit for liquid phase epitaxial growth of monocrystalline silicon carbide, and method for liquid phase epitaxial growth of monocrystalline silicon carbide

Patent metadata

Field	Value
Publication number	US-9252206-B2
Application number	US-201113995715-A
Country	US
Kind code	B2
Filing date	Jun 29, 2011
Priority date	Dec 24, 2010
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

The cost of liquid phase epitaxial growth of a monocrystalline silicon carbide is reduced. A feed material 11 is such that when a surface layer thereof containing a polycrystalline silicon carbide with a 3C crystal polymorph is subjected to X-ray diffraction, a diffraction peak corresponding to a (111) crystal plane and a diffraction peak other than the diffraction peak corresponding to the (111) crystal plane are observed as diffraction peaks corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph. A seed material 12 is such that when a surface layer thereof containing a polycrystalline silicon carbide with a 3C crystal polymorph is subjected to X-ray diffraction, a first-order diffraction peak corresponding to a (111) crystal plane is observed as a diffraction peak corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph but no other first-order diffraction peak having a diffraction intensity of 10% or more of the diffraction intensity of the first-order diffraction peak corresponding to the (111) crystal plane is observed.

First claim

The invention claimed is:

1. A unit for liquid phase epitaxial growth of a monocrystalline silicon carbide, the unit comprising a seed material and a feed material, wherein
the feed material includes a surface layer containing a polycrystalline silicon carbide with a 3C crystal polymorph and is such that upon X-ray diffraction of the surface layer a diffraction peak corresponding to a (111) crystal plane and a diffraction peak other than the diffraction peak corresponding to the (111) crystal plane are observed as diffraction peaks corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph,
the seed material includes a surface layer containing a polycrystalline silicon carbide with a 3C crystal polymorph is such that upon X-ray diffraction of the surface layer a first-order diffraction peak corresponding to a (111) crystal plane is observed as a diffraction peak corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph but no other first-order diffraction peak having a diffraction intensity of 10% or more of the diffraction intensity of the first-order diffraction peak corresponding to the (111) crystal plane is observed, and
the seed material and the feed material are heated in a position facing each other with a silicon melt layer therebetween to form a concentration gradient of graphite melting in the silicon melt layer and the monocrystalline silicon carbide is epitaxially grown on the seed material using the concentration gradient.

2. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 1 , wherein the first-order diffraction peak corresponding to the (111) crystal plane upon X-ray diffraction of the surface layer of the feed material is a main diffraction peak having the highest diffraction intensity among first-order diffraction peaks corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph.

3. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 1 , wherein the diffraction peak observed upon X-ray diffraction of the surface layer of the feed material and other than the diffraction peak corresponding to the (111) crystal plane includes at least one diffraction peak, each corresponding to one of a (200) crystal plane, a (220) crystal plane, and a (311) crystal plane.

4. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 3 , wherein the diffraction peak observed upon X-ray diffraction of the surface layer of the feed material and other than the diffraction peak corresponding to the (111) crystal plane includes diffraction peaks, each corresponding to one of the (200) crystal plane, the (220) crystal plane, and the (311) crystal plane.

5. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 1 , wherein the sum of the intensities of first-order diffraction peaks other than the first-order diffraction peak corresponding to the (111) crystal plane upon X-ray diffraction of the surface layer of the feed material is 10% or more of the sum of the intensities of all the first-order diffraction peaks.

6. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 1 , wherein
each of the feed material and the seed material includes a surface layer containing a polycrystalline silicon carbide with a 3C crystal polymorph and is such that upon X-ray diffraction of the surface layer at least one first-order diffraction peak is observed, each first-order diffraction peak corresponding to one of a (111) crystal plane, a (200) crystal plane, a (220) crystal plane, and a (311) crystal plane, and
the average crystallite diameter calculated from the at least one first-order diffraction peak of the feed material is smaller than that calculated from the at least one first-order diffraction peak of the seed material.

7. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 6 , wherein the average crystallite diameter calculated from the first-order diffraction peak observed upon X-ray diffraction of the surface layer of the feed material and corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph is 700 A or less.

8. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 7 , wherein
upon X-ray diffraction of the surface layer of the feed material a first-order diffraction peak corresponding to the (111) crystal plane and at least one first-order diffraction peak each corresponding to one of the (200) crystal plane, the (220) crystal plane, and the (311) crystal plane are observed, and
(I 1 /I 0 ) −1 ·D 2 is equal to or smaller than 10 8 ,
where:
I 0 represents the sum of the intensity of the first-order diffraction peak corresponding to the (111) crystal plane and the total intensity of the at least one first-order diffraction peak each corresponding to one of the (200) crystal plane, the (220) crystal plane, and the (311) crystal plane;
I 1 represents the total intensity of the at least one first-order diffraction peak each corresponding to one of the (200) crystal plane, the (220) crystal plane, and the (311) crystal plane; and
D represents the average crystallite diameter calculated from the at least one first-order diffraction peak each corresponding to one of the (200) crystal plane, the (220) crystal plane, and the (311) crystal plane.

9. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 6 , wherein the average crystallite diameter calculated from the first-order diffraction peak observed upon X-ray diffraction of the surface layer of the seed material and corresponding to the polycrystalline silicon carbide with a 3C crystal polymorph is more than 700 A.

10. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 1 , wherein the feed material is smaller than the seed material in terms of proportion of (111) crystal planes having an orientation angle of 67.5° or more in the (111) crystal planes observed by X-ray diffraction of the surface layer.

11. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 10 , wherein the proportion of (111) crystal planes having an orientation angle of 67.5° or more in the (111) crystal planes observed by X-ray diffraction of the surface layer of the feed material is less than 80%.

12. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 10 , wherein the proportion of (111) crystal planes having an orientation angle of 67.5° or more in the (111) crystal planes observed by X-ray diffraction of the surface layer of the seed material is 80% or more.

13. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 1 , wherein an LO peak derived from a polycrystalline silicon carbide with a 3C crystal polymorph is observed upon Raman spectroscopic analysis of each of the surface layers of the feed material and the seed material with an excitation wavelength of 532 nm, and the feed material is smaller than the seed material in terms of absolute amount of shift of the LO peak from 972 cm −1 .

14. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbide according to claim 13 , wherein the absolute amount of shift of the LO peak from 972 cm −1 in the feed material is less than 4 cm −1 .

15. The unit for liquid phase epitaxial growth of a monocrystalline silicon carbid

Assignees

• Torimi Satoshi
• Nogami Satoru
• Matsumoto Tsuyoshi
• Toyo Tanso Co

Inventors

• Torimi Satoshi
• Nogami Satoru
• Matsumoto Tsuyoshi

Classifications

• H10P14/3458

  Monocrystalline · CPC title

• C30B19/12

  characterised by the substrate · CPC title

• C30B29/36

  Carbides · CPC title

• C30B19/00 Primary

  Liquid-phase epitaxial-layer growth · CPC title

• H10D62/8325

  Silicon carbide · CPC title