{"title":"Impact of growth temperature on heterostructure interface steepness in ultraviolet-B AlGaN-based laser diodes","authors":"Takumu Saito, Rintaro Miyake, Ryoya Yamada, Yoshinori Imoto, Shundai Maruyama, Yusuke Sasaki, Shogo Karino, Sho Iwayama, Hideto Miyake, Koichi Naniwae, Satoshi Kamiyama, Tetsuya Takeuchi, Motoaki Iwaya","doi":"10.1063/5.0242536","DOIUrl":null,"url":null,"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.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"32 1","pages":""},"PeriodicalIF":3.5000,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Physics Letters","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1063/5.0242536","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, APPLIED","Score":null,"Total":0}
引用次数: 0
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.
期刊介绍:
Applied Physics Letters (APL) features concise, up-to-date reports on significant new findings in applied physics. Emphasizing rapid dissemination of key data and new physical insights, APL offers prompt publication of new experimental and theoretical papers reporting applications of physics phenomena to all branches of science, engineering, and modern technology.
In addition to regular articles, the journal also publishes invited Fast Track, Perspectives, and in-depth Editorials which report on cutting-edge areas in applied physics.
APL Perspectives are forward-looking invited letters which highlight recent developments or discoveries. Emphasis is placed on very recent developments, potentially disruptive technologies, open questions and possible solutions. They also include a mini-roadmap detailing where the community should direct efforts in order for the phenomena to be viable for application and the challenges associated with meeting that performance threshold. Perspectives are characterized by personal viewpoints and opinions of recognized experts in the field.
Fast Track articles are invited original research articles that report results that are particularly novel and important or provide a significant advancement in an emerging field. Because of the urgency and scientific importance of the work, the peer review process is accelerated. If, during the review process, it becomes apparent that the paper does not meet the Fast Track criterion, it is returned to a normal track.