Patent Number: 8,871,025

Title: SiC single crystals with reduced dislocation density grown by step-wise periodic perturbation technique

Abstract: In a crystal growth method, a seed crystal 8 and a source material 4 are provided in spaced relation inside of a growth crucible 6. Starting conditions for the growth of a crystal 14 in the growth crucible 6 are then established therein. The starting conditions include: a suitable gas inside the growth crucible 6, a suitable pressure of the gas inside the growth crucible 6, and a suitable temperature in the growth crucible 6 that causes the source material 4 to sublimate and be transported via a temperature gradient in the growth crucible 6 to the seed crystal 8 where the sublimated source material precipitates. During growth of the crystal 14 inside the growth crucible 6, at least one of the following growth conditions are intermittently changed inside the growth crucible 6 a plurality of times: the gas in the growth crucible 6, the pressure of the gas in the growth crucible 6, and the temperature in the growth crucible 6.

Inventors: Gupta; Avinash (Basking Ridge, NJ), Chakrabarti; Utpal K. (Allentown, PA), Chen; Jihong (St. Charles, MO), Semenas; Edward (Allentown, PA), Wu; Ping (Warren, NJ)

Assignee: II-VI Incorporated

International Classification: C30B 28/14 (20060101)

Expiration Date: 2018-10-28 0:00:00