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US-12617686-B2 - Vapor deposition apparatus and techniques using high purity polymer derived silicon carbide

US12617686B2US 12617686 B2US12617686 B2US 12617686B2US-12617686-B2

Abstract

Organosilicon chemistry, polymer derived ceramic materials, and methods. Such materials and methods for making polysilocarb (SiOC) and Silicon Carbide (SIC) materials having 3-nines, 4-nines, 6-nines and greater purity. Vapor deposition processes and articles formed by those processes utilizing such high purity SiOC and SiC.

Inventors

  • Mark S. Land

Assignees

  • PALLIDUS, INC.

Dates

Publication Date
20260505
Application Date
20230626

Claims (19)

  1. 1 . A method of making a boule for the production of a silicon carbide wafer, having a diameter of from about 6 inches to about 10 inches, the wafer characterized with properties comprising: a dopant and a thickness of about 300 to 800 μm; the method comprising the steps of: forming a vapor from a doped polymer derived ceramic SiC starting material; wherein the doped polymer derived ceramic SiC starting material comprises a dopant held by a polymer derived ceramic SiC material; wherein the doped polymer derived ceramic SiC starting material has a purity of at least about 5 nines; depositing the vapor on a seed crystal to form a boule; and, providing the boule to a wafer manufacturing process.
  2. 2 . The method of claim 1 , wherein the dopant comprises vanadium.
  3. 3 . The method of claim 1 , wherein the dopant consists essentially of vanadium.
  4. 4 . The method of claim 1 , wherein the dopant comprises aluminum.
  5. 5 . The method of claim 1 , wherein the dopant consists essentially of aluminum.
  6. 6 . The method of claim 1 , wherein the dopant comprises boron.
  7. 7 . The method of claim 1 , wherein the dopant consists essentially of boron.
  8. 8 . The method of claim 1 , wherein the dopant comprises phosphorus.
  9. 9 . The method of claim 1 , wherein the dopant consists essentially of phosphorus.
  10. 10 . The method of claim 1 , wherein the dopant comprises nitrogen.
  11. 11 . The method of claim 1 , wherein the dopant consists essentially of nitrogen.
  12. 12 . The method of claim 1 , wherein the wafer is a semi-insulating wafer.
  13. 13 . The method of claim 1 , wherein the wafer is an n-type wafer.
  14. 14 . The method of claim 1 , wherein the wafer is a p-type wafer.
  15. 15 . The method of claim 4 or 6 , wherein the wafer is a p-type wafer.
  16. 16 . The method of claim 1, 2 or 3 , wherein the wafer is further characterized with a property comprising an RT greater than or equal to 1E5 Ω·cm.
  17. 17 . The method of claim 1, 12, 13 or 14 , wherein the wafer is further characterized with a property comprising orientation: <0001>±0.5° or less.
  18. 18 . The method of claim 1, 12, 13 or 14 , wherein the wafer is further characterized with a property comprising a micropipe density of <10 cm-2.
  19. 19 . The method of claim 1, 12, 13 or 14 , wherein the wafer is further characterized with a property comprising a Bow/Warp/TTV <45 μm.

Description

This application is a continuation of U.S. patent application Ser. No. 17/000,552, filed Aug. 24, 2020; which is a continuation of U.S. patent application Ser. No. 15/275,055, filed Sep. 23, 2016, which application: (i) claims under 35 U.S.C. § 119 (e)(1) the benefit U.S. provisional application Ser. No. 62/232,355 filing date of Sep. 24, 2015; and (ii) is a continuation-in-part of U.S. patent application Ser. No. 14/864,125 filed Sep. 24, 2015, which claims under 35 U.S.C. § 119 (e)(1) the benefit of US provisional application Ser. No. 62/055,461 filing date of Sep. 25, 2014 and U.S. provisional application Ser. No. 62/055,497 filing date of Sep. 25, 2014, the entire disclosures of each of which are incorporated herein by reference. BACKGROUND OF THE INVENTION Field of the Invention The present inventions relate to improvements in vapor deposition processes and crystal growth and materials growth that can be achieved using the novel ultra pure SiC and SiOC materials that are disclosed and taught in patent applications, Ser. No. 14/864,539 (US Publication No. 2016/0208412), Ser. No. 14/864,125 (US Publication No. 2016/0207782), and PCT/US2015/051997 (Publication No. WO 2016/049344), filed contemporaneously herewith, the entire disclosures of each of which are incorporated herein by reference. The use of these materials having 6-nines, 7-nines, 8-nines and greater purity provides from many advantages in vapor deposition growth of crystals. And provides for new and refined vapor deposition apparatus and systems for crystal growth. The ultra high purity materials provide, among other things: faster crystal growth, the ability to grow larger and purer seed crystals or starting plates for the deposition process; the ability to use a larger percentage of the starting material used in the apparatus. Thus, enhanced control, greater efficiencies and high quality can be obtained by using the high purity and ultra pure materials in vapor deposition techniques. In recent years the demand for high purity silicon carbide, and in particular high purity single crystalline carbide materials for use in end products, such as a semiconductor, has been increasing, but is believe to be unmet. For example, “single crystals are gaining more and more importance as substrate[s] for high frequency and high power silicon carbide electronic devices.” Wang, et. al, Synthesis of High Power Sic Powder for High-resistivity SiC Single crystals Growth, p. 118 (J. Mater. Sic. Technol. Vol. 23, No 1, 2007)(hereinafter Wang). To obtain these high purity silicon carbide end products, silicon carbide powder as a starting or raw material must be exceedingly pure. However, “[c]ommercially available SiC powder is usually synthesized by carbothermal reduction of silica. Unfortunately, it is typically contaminated to the level that makes it unsuitable for SiC growth.” Wang, at p. 118. The longstanding need for, and problem of obtaining high purity silicon carbide, and the failing of the art to provide a viable (both from a technical and economical standpoint) method of obtaining this material was also recognized in Zwieback et al., 2013/0309496 (“Zwieback”), which provides that the “[a]vailability of high-purity SiC source material is important for the growth of SiC single crystals in general, and it is critical for semi-insulating SiC crystals” (Zwieback at ¶0007). Zwieback goes on to state that the prior methods including liquid based methods have consistently failed to meet this need: “While numerous modifications of the Acheson process have been developed over the years, the produced SiC material always contain high concentrations of boron, nitrogen aluminum and other metals, and is unsuitable as a source material for the growth of semiconductor-quality SiC crystals” (Zwieback at ¶0009); “commercial grade bulk SiC produced by CVD is not pure enough for the use as a source in SiC crystal growth” (Zwieback at ¶0010); the liquid process “produced SiC material contains large concentrations of contaminates and is unsuitable for the growth of semiconductor-quality SiC crystals” (Zwieback at ¶0011); and, the direct synthesis of SiC provides an impure material that “precludes the use of such material” (Zwieback at ¶0015). Zwieback itself seeks to address this long-standing need with a complex, multi-step version of what appears to be the direct process in a stated attempt to provide high purity SiC. It is believed that this process is neither technically or economically viable; and therefor that it cannot solve the longstanding need to provide commercial levels of high purity SiC. Thus, although there are other known methods of obtaining silicon carbide, it is believed that none of these methods provide the requisite technical, capacity, and economical viability to provide the purity levels, amounts, and low cost required for commercial utilization and applications; and in particular to meet the ever increasing demands for semiconductor grade material, an