SiC P-TYPE, AND LOW RESISTIVITY, CRYSTALS, BOULES, WAFERS AND DEVICES, AND METHODS OF MAKING THE SAME
A doped SiOC liquid starting material provides a p-type polymer derived ceramic SiC crystalline materials, including boules and wafers. P-type SiC electronic devices. Low resistivity SiC crystals, wafers and boules, having phosphorous as a dopant. Polymer derived ceramic doped SiC shaped charge source materials for vapor deposition growth of doped SiC crystals.
1 . A method of making an SiC crystal having a predetermined electrical property, the method comprising:
a. placing an SiC source material in a vapor deposition apparatus;
b. the SiC source material comprising silicon, carbon and a dopant,
i. wherein the dopant is selected to provide the predetermined electrical property to the SiC crystal;
ii. wherein a position of the dopant with respect to the silicon and the carbon in the source material is fixed;
c. adding an inert gas into the vapor deposition apparatus, and controlling the pressure in the vapor deposition apparatus;
d. heating the SiC source material to thereby form a flux, wherein the flux comprises silicon, carbon and the dopant; and,
e. depositing the flux on a growth face of an SiC crystal to thereby grow the SiC crystal;
f. wherein the SiC crystal has the predetermined electrical property.
2 . The method of claim 1 , wherein the source material consists essentially of silicon, carbon and the dopant.
3 . The method of claim 1 , wherein the source material consists of silicon, carbon and the dopant.
4 . The method of claim 1 , wherein the dopant comprises one or more of the elements in Group 15 of the periodic table.
5 . The method of claim 1 , wherein the dopant comprises phosphorous.
6 . The method of claim 1 , wherein the dopant consists essentially of phosphorous.
7 . The method of claim 1 , wherein the dopant consists of phosphorous.
8 . The method of claim 1 , wherein the dopant comprises one or more of the elements in Group 13 of the periodic table.
9 . The method of claim 1 , wherein the dopant comprises boron.
10 . The method of claim 1 , wherein the dopant consists essentially of boron.
11 . The method of claim 1 , wherein the dopant consists of boron.
12 . The method of claim 1 , wherein the dopant comprises aluminum.
13 . The method of claim 1 , wherein the dopant consists essentially of aluminum.
14 . The method of claim 1 , wherein the dopant consists of aluminum.
15 . The method of claim 1 , wherein the predetermined electrical property comprises a net charge, and the net charge is positive, whereby the crystal is a p-type crystal.
16 . The method of claim 1 , wherein the predetermined electrical property comprises a net charge, and the net charge is negative, whereby the crystal is an n-type crystal.
17 . The method of claim 1 , wherein the predetermined electrical property comprises resistivity.
18 . The method of claim 1 , wherein the predetermined electrical property comprises a resistivity of 0.013 ohm-cm and less.
19 . The method of claim 1 , wherein the predetermined electrical property comprises a resistivity of about 0.010 ohm-cm and less.
20 . The method of claim 1 , wherein the predetermined electrical property comprises a resistivity from about 0.01 ohm-cm to about 0.001 ohm-cm.
21 . The method of claim 1 , wherein the predetermined electrical property comprises a resistivity from about 0.009 ohm-cm to about 0.004 ohm-cm.
22 . The method of claim 1 , wherein no other materials are added to the flux after it is formed from the source material.
23 . The method of claim 1 , wherein no other materials are added to the vapor deposition apparatus.
24 . The method of claim 1 , wherein the SiC source material is the only source of the dopant.
25 . The method of claim 1 , wherein no alloys are present, and thereby the method is alloy free.
26 . The method of claim 1 , wherein the vapor deposition apparatus is a physical vapor transport apparatus.
27 . The method of claim 1 , wherein the flux is a directional flux.
28 . The method of claim 1 , wherein the SiC source material is shaped charge.
29 . The method of claim 1 , wherein the crystal has a diameter of at least about 100 mm and a height of at least about 25 mm.
30 . The method of claim 1 , wherein the crystal has a diameter from about 100 mm to about 150 mm, and a height of about 25 mm to about 125 mm.
31 . A method of making a p-type SiC crystal, the method comprising:
a. placing a shaped charge SiC source material in a vapor deposition apparatus;
b. the shaped charge SiC source material consisting essentially of silicon, carbon and an amount of acceptor atoms held in a position in the shaped charge SiC source material;
c. wherein the position of the acceptor atoms with respect to the silicon and the carbon in the shaped charge source material is fixed;
d. heating the shaped charge SiC source material and thereby forming a flux through sublimation of the shaped charge source material; wherein the flux comprises silicon, carbon and a portion of the amount of acceptor atoms; and,
e. depositing the flux on a growth face of a p-type SiC crystal to thereby grow the p-type SiC crystal; wherein at least some of the acceptor atoms in the flux form substitutional atomic impurities in the p-type SiC crystal.
32 . The method of claim 31 , wherein the acceptor atoms comprise boron.
33 . The method of claim 31 , wherein the acceptor atoms comprise aluminum.
34 . The method of claim 31 , wherein the source material does not contain an alloy.
35 . The method of claim 31 , wherein the source material is the only source of acceptor atoms.
36 . (canceled)
37 . The method of claim 31 , wherein an inert gas is added to the vapor deposition apparatus, and no other gases are added to the vapor deposition apparatus.
38 . (canceled)
39 . The method of claim 31 , wherein the p-type crystal has a diameter from about 100 mm to about 150 mm, and a height of about 25 mm to about 125 mm.
40 . (canceled)
41 . The method of claim 31 , wherein the p-type crystal has a resistivity from 2.0 ohm-cm to about 0.1 ohm-cm.
42 . (canceled)
43 . The method of claim 31 , wherein p-type crystal has a resistivity from 0.013 ohm-cm to about 0.004 ohm-cm.
44 . (canceled)
45 . (canceled)
46 . The method of claim 31 , wherein p-type crystal has a resistivity from about 0.009 ohm-cm to about 0.004 ohm-cm.
47 . The method of claim 31 , wherein during the growth of the p-type crystal the dopant remains fixed in the source material until it is sublimed to form the flux.
48 . A method of making a low resistivity n-type SiC crystal, the method comprising:
a. placing a shaped charge SiC source material in a vapor deposition apparatus;
b. the shaped charge SiC source material consisting essentially of silicon, carbon and an amount of donor atoms held in a position in the shaped charge SiC source material;
c. wherein the position of the acceptor atoms with respect to the silicon and the carbon in the shaped charge source material is fixed;
d. heating the shaped charge SiC source material and thereby forming a flux through sublimation of the shaped charge source material; wherein the flux comprises silicon, carbon and a portion of the amount of acceptor atoms; and,
e. depositing the flux on a growth face of a n-type SiC crystal to thereby grow the n-type SiC crystal; wherein at least some of the donor atoms in the flux form substitutional atomic impurities in the n-type SiC crystal.
49 . The method of claim 48 , wherein the donor atoms comprise one or more of the elements in Group 15 of the periodic table.
50 . The method of claim 48 , wherein the donor atoms comprise phosphorous.
51 . The method of claim 48 , wherein the donor atoms consist essentially of phosphorous.
52 . (canceled)
53 . (canceled)
54 . (canceled)
55 . The method of claim 48 , wherein an inert gas is added to the vapor deposition apparatus, and no other gases are added to the vapor deposition apparatus.
56 . (canceled)
57 . (canceled)
58 . The method of claim 48 , wherein the n-type crystal has a resistivity of 0.013 ohm-cm and less.
59 . (canceled)
60 . (canceled)
61 . (canceled)
62 . (canceled)
63 . The method of claim 48 , wherein during the growth of the n-type crystal the acceptor atoms remain fixed in the source material until sublimed to form the flux.
64 . The method of claims 1, 31 or 48 , comprising p-type crystal growth on a C face of an SiC seed crystal.
65 . The method of claims 1, 31 or 48 , comprising p-type crystal growth on an S face of an SiC seed crystal.
66 . The method of claims 1, 31 or 48 , comprising p-type crystal growth on a C face of an SiC seed crystal, wherein the SiC seed crystal has a 4H or 6H polytype.
67 . The method of claims 1, 31 or 48 , comprising p-type crystal growth on an S face of an SiC seed crystal, wherein the SiC seed crystal has a 4H or 6H polytype.