[8a-N101-1~11] 15.4 III-V-group nitride crystals

9:15 AM - 9:30 AM JST(12:15 AM - 12:30 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation Award

[8a-N101-2] The effect of AlGaN interlayer on Time-resolved photoluminescence properties of InGaN/GaN Quantum dots

〇Katsuki Sato¹, Yuto Nakama¹, Riku Iwasaki¹, Zades Alexander¹, Koshiro Arai¹, Yuta Nakayama¹, Ying Gong², Wenxian Yang², Shulong Lu², Atsushi Tackeuchi¹ (1.Waseda Univ., 2.SINANO)

Keywords:

InGaN Quantum dots,AlGaN interlayer,Photoluminescence properties of semiconductor

In InGaN-based materials, increasing the In composition to achieve longer-wavelength emission leads to an increase in crystal defects and a decrease in emission efficiency, which is known as the “green gap” problem. In this study, an Al_xGa1-xN insertion layer was introduced into InGaN/GaN quantum dot structures, and photoluminescence (PL) measurements were performed on samples with Al compositions of x = 0, 10, and 20%. Time-resolved measurements were carried out using a streak camera, and the results were compared to investigate the effect of the AlGaN insertion layer on the luminescence properties of InGaN/GaN quantum dots.The results showed that the sample with an Al composition of 10% exhibited the longest-wavelength emission peak and a longer emission lifetime. Based on these results, we discuss the possibility that the AlGaN insertion layer affects both the morphology of the InGaN quantum dots and In incorporation. In contrast, the sample with an Al composition of 20% showed an emission peak at a shorter wavelength than that of the 10% sample, along with a shorter emission lifetime. This result suggests the possible formation of crystal defects with increasing Al composition.