1. A method of producing a silicon carbide boule having a substantially single polytype, the method comprising:
forcing nucleation sites on a surface of a silicon carbide seed crystal having the substantially single polytype to a predefined pattern; and
growing the silicon carbide boule utilizing physical vapor transport (PVT) so as to provide selective preferential growth of silicon carbide on the silicon carbide seed crystal corresponding to the predefined pattern;
wherein forcing nucleation sites comprises forming a pattern of material other than silicon carbide on a surface of the silicon carbide seed crystal thereby selectively exposing portions of the seed crystal to define the nucleation sites in the selectively exposed portions of the seed crystal;
wherein the pattern of material other than silicon carbide provides a pattern of regions having a reduced sticking coefficient than that of the exposed portions of the seed crystal; and
wherein the silicon carbide boule grows laterally above the material other than silicon carbide.
2. The method of claim 1, wherein the pattern comprises stripes on the seed crystal.
3. The method of claim 1, wherein the pattern comprises a plurality of posts on the seed crystal.
4. The method of claim 1, wherein the pattern comprises a layer of material having a plurality of openings therein so as to expose portions of the seed crystal.
5. The method of claim 4, wherein the openings are substantially circular.
6. The method of claim 1, wherein the material other than silicon carbide comprises graphite.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for producing a purified scyllo-inositol, comprising:
a first step of precipitating a scyllo-inositolboric acid complex by adding boric acid and a metal salt into a liquid mixture containing scyllo-inositol and neutral sugar other than scyllo-inositol in an amount by mol two times or more that of scyllo-inositol dissolved in the liquid mixture, and by adjusting the pH of the liquid mixture to 8.0 to 11.0;
a second step of separating the complex from the liquid mixture;
a third step of dissolving the separated complex into acid to cleave into scyllo-inositol and boric acid to obtain an acidic solution or acidic suspension; and
a fourth step of adding ethanol or methanol to the acidic solution or acidic suspension to precipitate scyllo-inositol and purifying the scyllo-inositol from the acidic solution or acidic suspension,
wherein the metal salt to be added is one or more kinds of metal salts selected from the group consisting of NaCl, NaHCO3, Na2CO3, Na2SO4, NaHSO4, NaH2PO4, Na2HPO4, Na3PO4, borax, KCl, KHCO3, K2CO3, K2SO4, KHSO4, KH2PO4, K2HPO4, K3PO4, MgCl2, MgCO3, and MgSO4, and wherein the ethanol is added in a volume 0.3 to 3 times the volume of the acidic solution or acidic suspension, or the methanol is added in a volume 0.3 to 5 times the volume of the acidic solution or acidic suspension.
2. The method according to claim 1, wherein, in the first step, the amounts of the boric acid and metal salt to be added are two to three times the amount by mol of the scyllo-inositol dissolved in the liquid mixture.
3. The method according to claim 1, wherein, in the first step, the pH of the liquid mixture is adjusted to 9.0 to 10.0.
4. The method according to claim 1, wherein the ethanol is added in a volume 0.6 to 1.5 times the volume of the acidic solution or acidic suspension, or the methanol is added in a volume 0.9 to 2 times the volume of the acidic solution or the acidic suspension.