Impact of growth temperature on heterostructure interface steepness in ultraviolet-B AlGaN-based laser diodes
Abstract
This study investigates the steepness of the heterostructure interface between the p-side optical-waveguide and electron blocking layer (EBL) in ultraviolet-B (UV-B) laser diodes (LDs), focusing on the impact of growth temperature. The results revealed that lowering the growth temperature significantly reduced the thickness of the “unintended compositionally graded layer” a diffusion layer formed at the interface through solid-phase diffusion. However, a bottleneck also existed in LDs with extremely steep interfaces, where the diode characteristics could not be obtained due to the device's high resistance. This study highlights the trade-off between the steepness of the interfaces in the AlGaN heterostructure and diode performance, indicating the need for further optimization to achieve high-performance UV-B LDs. Specifically, future efforts should focus on refining growth conditions to reduce impurity concentrations resulting from low-temperature growth and controlling the thickness of individual layers, such as the EBL, to address high resistance and achieve high-performance UV-B LDs.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (13)
Takumu Saito
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Rintaro Miyake
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Ryoya Yamada
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Yoshinori Imoto
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Shundai Maruyama
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Yusuke Sasaki
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Shogo Karino
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Sho Iwayama
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Hideto Miyake
Koichi Naniwae
Ushio, Inc 3 ., Gotenba 412-0038,
Satoshi Kamiyama
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Tetsuya Takeuchi
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,
Motoaki Iwaya
Department of Materials Science and Engineering, Meijo University 1 , Nagoya 468-8502,