STABILITY OF HYDROGEN IN SCALMGO4

Hydrogen as 2H was incorporated into ScAlMgO4 by both ion implantation and by exposure to a plasma at 250 degrees C. In the implanted materi al diffusion begins at similar to 500 degrees C and most of the hydrog en is lost by less than or equal to 750 degrees C. This thermal stabil ity for hydrogen retention is considerably lower than for other substr ate materials for GaN epilayer growth, such as Al2O3 and SiC. There is minimal permeation of H-2 from a plasma at 250 degrees C (D-H < 5 x 1 0(-16) cm(2) s(-1)) in ScAlMgO4, and thus unintentional hydrogen incor poration into GaN overlayers should be minimal at typical growth tempe ratures. (C) 1997 Elsevier Science Ltd.