[15a-A408-1~10] 6.2 Carbon-based thin films

▲ [15a-A408-8] Misorientation Angle of Heteroepitaxial Diamond on Sapphire Misoriented Substrate

〇(M1)JACQUES DAGBETO¹, Koji Koyama², Seongwoo Kim², Makoto Kasu¹ (1.Saga Univ., 2.Orgray Co., Ltd)

Keywords:Diamond semiconductor, misoriented sapphire substrate, thin films

Diamond power devices will exceed SiC and GaN, because of its exceptional physical properties. Lately, we improved high-quality (001) heteroepitaxial diamond on sapphire (110) misoriented 7^o substrate toward [0001] c-direction, in which XRC FWHM 004 and 311 are 89.136 and 145 arcsec, respectively, the lowest ever reported. In this work, we investigate misorientation angle (α) of sapphire substrate, Iridium buffer layer and diamond layer.
We found that sapphire misorientation angle, α(sapp), is 6.92~6.94^o. Surprisingly, α(Ir) was 5.69~5.81^o, which is lower than α(sapp). Diamond’s misorientation angle, α(dia), is found to be 6.66~6.82 for N-free and 6.25~6.38 for N-doped.
The phenomenon that α(Ir) < α(dia) < α(sapp), may be caused by lattice relaxation during growth.