US 12,227,873 B2
Aluminum nitride single crystals having large crystal augmentation parameters
Robert T. Bondokov, Latham, NY (US); Thomas Miebach, Malta, NY (US); Jianfeng Chen, Clifton Park, NY (US); Takashi Suzuki, Fuji (JP); and Leo J. Schowalter, Latham, NY (US)
Assigned to CRYSTAL IS, INC., Green Island, NY (US)
Filed by Robert T. Bondokov, Latham, NY (US); Thomas Miebach, Malta, NY (US); Jianfeng Chen, Clifton Park, NY (US); Takashi Suzuki, Fuji (JP); and Leo J. Schowalter, Latham, NY (US)
Filed on Aug. 12, 2020, as Appl. No. 16/991,278.
Claims priority of provisional application 62/887,033, filed on Aug. 15, 2019.
Prior Publication US 2021/0047751 A1, Feb. 18, 2021
Int. Cl. C30B 23/08 (2006.01); C30B 23/02 (2006.01); C30B 25/20 (2006.01); C30B 29/40 (2006.01); C30B 23/06 (2006.01)
CPC C30B 23/08 (2013.01) [C30B 23/025 (2013.01); C30B 25/20 (2013.01); C30B 29/403 (2013.01); C30B 23/06 (2013.01)] 28 Claims
OG exemplary drawing
 
1. An AlN single crystal having a diameter that increases, along at least a portion of a length of the AlN single crystal, from a minimum diameter, ranging from 50 mm to 100 mm, to a maximum diameter, the AlN single crystal having a crystal augmentation parameter (CAP), in mm, greater than 20, the CAP being defined by:

OG Complex Work Unit Math
wherein AE, in mm2, is the cross-sectional area of the AlN single crystal at the maximum diameter, dE is the maximum diameter of the AlN single crystal in mm, AS, in mm2, is the cross-sectional area of the AlN single crystal at the minimum diameter, dS is the minimum diameter in mm, and LE is an expansion length, in mm, of the at least a portion of the AlN single crystal along which the diameter increases from the minimum diameter to the maximum diameter.