Insight into gain and transient response characteristics of AlGaN/GaN hetero-junction based UV photodetectors: Case study on the role of incident light intensity

被引：0

作者：

Li, Wenxin ^{[1
]}

Wang, Yifu ^{[1
]}

Gu, Guangyang ^{[1
]}

Ren, Fangfang ^{[1
,2
]}

Zhou, Dong ^{[1
]}

Xu, Weizong ^{[1
,2
]}

Zhou, Feng ^{[1
]}

Chen, Dunjun ^{[1
]}

Zhang, Rong ^{[1
,2
]}

Zheng, Youdou ^{[1
]}

Lu, Hai ^{[1
,2
,3
]}

机构：

[1] Nanjing Univ, Sch Elect Sci & Engn, Nanjing 210093, Peoples R China

[2] Hefei Natl Lab, Hefei 230088, Peoples R China

[3] MOE, Key Lab Optoelect Devices & Syst Extreme Performan, Nanjing 210023, Peoples R China

来源：

APPLIED PHYSICS LETTERS | 2024年 / 125卷 / 23期

关键词：

PERFORMANCE;

D O I：

10.1063/5.0227700

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Gain and response speed are two key performance parameters for high sensitivity photodetectors (PDs). However, the effect of incident light intensity on gain and transient response properties of AlGaN/GaN hetero-junction based PDs are still not fully understood. Here, we design and fabricate an AlGaN/GaN hetero-junction based ultraviolet (UV) PD with interdigitated electrodes formed by a conductive two-dimensional electron gas (2DEG) channel, which exhibits a low dark current of 2.92 x 10(-11) A and a high responsivity of 3060 A/W at 10 V bias. The high-gain AlGaN/GaN 2DEG PD has a similar working mechanism to those of traditional phototransistors, but its device architecture is evidently simplified. By investigating the variation of gain and transient response characteristics of the 2DEG PD as a function of incident UV light intensity, it has been concluded that the gain of the PD in a low-light intensity region is dominated by hole accumulation-induced electron escape from the 2DEG, while in a high-light intensity region, the gain is dominated by photoconductivity effect and limited by carrier recombination. This study provides guidance for future practical applications of AlGaN/GaN-based PDs in complex UV illumination environments.

引用

页数：6