US 12,460,314 B2
Silicon carbide substrate and method of growing SiC single crystal boules
Michael Vogel, Nuremberg (DE); Bernhard Ecker, Nuremberg (DE); Ralf Müller, Zirndorf (DE); Matthias Stockmeier, Egloffstein (DE); and Arnd-Dietrich Weber, Forchheim (DE)
Assigned to SICRYSTAL GMBH, Nuremberg (DE)
Filed by SICRYSTAL GMBH, Nuremberg (DE)
Filed on Feb. 21, 2023, as Appl. No. 18/172,202.
Application 18/172,202 is a division of application No. 16/492,000, granted, now 11,624,124, previously published as PCT/EP2018/055627, filed on Mar. 7, 2018.
Claims priority of application No. 17163515 (EP), filed on Mar. 29, 2017.
Prior Publication US 2023/0193508 A1, Jun. 22, 2023
Int. Cl. C30B 23/02 (2006.01); C30B 29/06 (2006.01); C30B 29/36 (2006.01)
CPC C30B 23/025 (2013.01) [C30B 29/06 (2013.01); C30B 29/36 (2013.01); Y10T 428/24942 (2015.01)] 15 Claims
OG exemplary drawing
 
1. Method of growing at least one SiC single crystal boule (108, 109) in a physical vapor transport growth system, the method comprising the steps of:
arranging an SiC powder source material (114) in a source material compartment (116),
arranging at least one SiC seed crystal within at least one growth compartment (118, 119), wherein said source material compartment (116) is connected to said at least one growth compartment (118, 119) for providing sublimated gaseous components to the at least one growth compartment (118, 119), and
applying an elevated temperature for generating the sublimated gaseous components that generate an SiC growth phase at the SiC seed crystal, so that an SiC volume single crystal boule (108, 109) is formed at the SiC seed crystal,
wherein the at least one growth compartment (118, 119) comprises a dopant source and/or a dopant sink for controlling a dopant concentration in a radial direction with reference to a longitudinal axis of the single crystal boule (108, 109) during the growth of the single crystal boule (108, 109) such that a dopant concentration in a central region of the single crystal boule (108, 109) differs from a dopant concentration in a peripheral region of the single crystal boule (108, 109), and
wherein the SiC powder source material comprises a dopant enriched material (126) in a region opposite to a central region of the seed crystal with a concentration of a doping element in the dopant enriched material (126) of at least 1·1020 cm−3 and wherein a concentration of the doping element in a lower doped outer SiC powder source material is lower than 5·1017 cm−3.