[18p-E202-1~22] 15.4 III-V-group nitride crystals

△ [18p-E202-4] Identification of Dislocation Characteristics in Na-flux grown GaN substrates by Means of Bright-Field X-ray Topography under Multiple-Diffraction Conditions

〇(M1)Hiroyuki Mizuochi¹, Tetsuya Tsurumaru¹, Yoshiyuki Tsusaka^1,2, Junji Matsui², Masayuki Imanishi³, Mamoru Imade³, Yusuke Mori³ (1.Grad. Sch. of Material Sci. Univ. of Hyogo, 2.Syn. Rad. Nano-Tech. Center, 3.Grad. Sch. of Eng. Osaka Univ.)

Keywords:bright-field X-ray topography under multiple-diffraction conditions, Na-flux grown GaN substrates, dislocations

We observed dislocation characteristics in Na-flux grown GaN substrates by means of bright-field X-ray topography under multiple-diffraction conditions. This technique has some advantages as follows. It is not necessary to place the CMOS camera at diffracted beam positions and we can take quickly plural X-ray topographs having specific diffraction vectors. According to disappearance rule of dislocation contrast, Burgers vectors of basal dislocations are determined to be a (1/3<11-20>type) and those of threading dislocations are determined to be a or a+c (1/3<11-23>type).