[15p-K401-1~15] 15.4 III-V-group nitride crystals

2:45 PM - 3:00 PM JST(5:45 AM - 6:00 AM UTC)

[15p-K401-6] The effect of the Al composition gradient layer at the interface between the electron blocking layer and the guide layer on the carrier injection efficiency in AlGaN-based UV-B laser diodes

〇(M1)Takumu Saito¹, Rintaro Miyake¹, Ryoya Yamada¹, Yoshinori Imoto¹, Shundai Maruyama¹, Yusuke Sasaki¹, Shogo Karino¹, Sho Iwayama¹, Hideto Miyake², Satoshi Kamiyama¹, Tetsuya Takeuchi¹, Motoaki Iwaya¹ (1.Meijo Univ., 2.Mie Univ.)

Keywords:

nitride,UV LD,metal organic vapor phase epitaxy

We achieved room-temperature pulsed operation of an AlGaN-based UV-B laser diode (LD) with a peak optical output of 150 mW. However, the carrier injection efficiency (ηi) remained around 10%, necessitating further improvement. One reported cause of low ηi is the unintended Al compositional gradient layer formed at the interface between the electron blocking layer and the guiding layer, but its impact has not been fully understood. In this study, we systematically investigated the effect of the Al compositional gradient layer on ηi using UV-B LDs fabricated by MOVPE.