[TuP3A] Epitaxy and process

2:00 PM - 4:00 PM JST(5:00 AM - 7:00 AM UTC)

[TuP3A-26 LN] Bi aggregates formed in InAsBi/GaAs periodic structure heated to over 600 °C by using in situ STEM observation

〇Yoriko Tominaga^1,2, Shohei Hayashi³, Ryuki Yokote¹, Shotaro Fujino¹, Kenta Yoshioka², Yuki Okamura², Mitsuki Yukimune⁴, Fumitaro Ishikawa⁵, Kouichi Akahane⁶ (1. AdSM, Hiroshima University (Japan), 2. AdSE, Hiroshima University (Japan), 3. Toray Research Center Inc. (Japan), 4. Grad. Sch. of Sci. and Eng., Ehime University (Japan), 5. RCIQE, Hokkaido University (Japan), 6. NICT (Japan))

Dilute bismide (Bi–) III–V compound semiconductors have recently attracted attention as candidate materials for the novel semiconductor laser diodes with near- and mid-infrared wavelengths. While the growth of quantum wells and nanowires composed of Bi–III–V compound semiconductors has been achieved towards the fabrication of the semiconductor devices, discussions about the methods for forming their quantum dots (QDs) are in their relatively early stages. In this study, to propose a new method for forming InAsBi QDs by thermal annealing, we performed in situ scanning transmission electron microscopy (STEM) observation while heating the InAsBi/GaAs periodic structures stepwise in a range between 300 to 800 °C. InAsBi/GaAs periodic structure with number of period being 10 was grown on GaAs substrate at 280 °C using molecular beam epitaxy. In situ STEM observation indicated that the dot-like shapes were formed by annealing over 600 °C and Bi aggregated inside the InAsBi layers in a point-like manner.