[14p-CE-1~4] 15.4 III-V-group nitride crystals

[14p-CE-1] [Young Scientist Presentation Award Speech] Formation mechanism of threading dislocations depending on initial III/V ratio in PAMBE-grown AlN layers on SiC substrates

〇Mitsuaki Kaneko¹, Tsunenobu Kimoto¹, Jun Suda¹ (1.Kyoto Univ.)

Keywords:Nitride semiconductor,MBE,dislocations

We have been developing a growth method of high quality AlN on 6H-SiC substrates by plasma-assisted molecular-beam epitaxy (PAMBE). In previous study, we have reported that initial III/V ratio increases by about 40% compared to the steady-state condition of the plasma cell when the growth is started just after plasma ignition. The threading dislocation density (TDD) of the AlN the growth of which started jusf after plasma ignistion is much higher than the previously reported AlN layers and short standby time after ignition was found to be effective to reduce TDD. In this study, for clarifing formation mechanism of the threading dislocations, ultra-thin AlN layers with and without standby time are grown and characterized.