US 11,705,322 B2
Group III nitride substrate, method of making, and method of use
Wenkan Jiang, Walnut, CA (US); Mark P. D'Evelyn, Vancouver, WA (US); Derrick S. Kamber, Camas, WA (US); Dirk Ehrentraut, Camas, WA (US); Jonathan D. Cook, Santa Barbara, CA (US); and James Wenger, Vancouver, WA (US)
Assigned to SLT TECHNOLOGIES, INC., Los Angeles, CA (US)
Filed by SLT Technologies, Inc, Los Angeles, CA (US)
Filed on May 22, 2020, as Appl. No. 16/882,219.
Claims priority of provisional application 62/975,078, filed on Feb. 11, 2020.
Prior Publication US 2021/0249252 A1, Aug. 12, 2021
Int. Cl. C30B 7/10 (2006.01); C30B 7/00 (2006.01); C30B 29/40 (2006.01); H01L 29/20 (2006.01); H01L 21/02 (2006.01); C30B 33/10 (2006.01); H01L 29/778 (2006.01); H01L 33/32 (2010.01)
CPC H01L 21/02005 (2013.01) [C30B 7/005 (2013.01); C30B 7/105 (2013.01); C30B 29/406 (2013.01); C30B 33/10 (2013.01); H01L 21/0254 (2013.01); H01L 21/02642 (2013.01); H01L 21/02647 (2013.01); H01L 29/2003 (2013.01); H01L 29/7788 (2013.01); H01L 33/32 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A free-standing crystal, comprising a group III metal and nitrogen, wherein the free-standing crystal comprises:
a wurtzite crystal structure;
a first surface having a maximum dimension greater than 40 millimeters in a first direction;
an average concentration of stacking faults below 103 cm−1;
an average concentration of threading dislocations between 101 cm−2 and 106 cm−2, wherein the average concentration of threading dislocations on the first surface varies periodically by at least a factor of two in the first direction, a period of the variation in the first direction being between 5 micrometers and 20 millimeters; and
a miscut angle that varies by 0.1 degree or less along the first direction and by 0.1 degree or less along a second direction orthogonal to the first direction in the central 80% of an area of the first surface of the free-standing crystal,
wherein
the first surface comprises a plurality of first regions, each of the plurality of first regions having a locally-approximately-linear array of threading dislocations with a concentration between 5 cm−1 and 105 cm−1,
the first surface further comprises a plurality of second regions, each of the plurality of second regions being disposed between an adjacent pair of the plurality of first regions and having a concentration of threading dislocations below 105 cm−2 and a concentration of stacking faults below 103 cm−1, and
the first surface further comprises a plurality of third regions, each of the plurality of third regions being disposed within one of the plurality of second regions or between an adjacent pair of second regions and having a minimum dimension between 10 micrometers and 500 micrometers and threading dislocations with a concentration between 103 cm−2 and 108 cm−2.