[TuP3A] Epitaxy and process

[TuP3A-18] Structural Evaluation of Thick Low-Temperature-Grown GaAs_1-xBi_x Films on GaAs(001) Substrates

〇Osamu Ueda¹, Noriaki Ikenaga², Kyosuke Ariyoshi³, Keisuke Minehisa⁴, Fumitaro Ishikawa⁴, Yoriko Tominaga³ (1. Meiji Uni. (Japan), 2. Kanazawa Inst. of Tech. (Japan), 3. Hiroshima Univ. (Japan), 4. Hokkaido Univ. (Japan))

Through transmission electron microscopy and related techniques, we performed structural evaluation of low-temperature-grown 2 micrometer thick GaAsBi films grown on GaAs substrates at 250 ℃ by molecular beam epitaxy. The results revealed that various types of dislocation segments are observed which correspond to parts of dislocation half loops. After annealing, bending of dislocations as well as generation of dislocation networks are observed. Furthermore, preferential formation of high density small Bi-related precipitates at dislocations and dislocation networks, and formation of isolated giant Bi precipitates were observed. Based on these results, generation mechanisms of these defects are discussed.