Interface-Embedded Pt-Plasmons Enhanced Self-Powered Deep-UV Photodetector
Zhihua Zheng, Zhongshu Xiong, Linlin Xu, Feng Wu, Munho Kim, Jiaxing Mao, Yunbin He, Jintong Xu, Jiangnan Dai, Changqing Chen
Abstract
Motivated by improving the performance of self-powered deep-UV (DUV) photodetector (PD), for the first time, Pt plasmonic nanoparticles (NPs) were embedded in hybrid PEDOT: PSS/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> -Ga2O3 heterojunction interface to maximize light-matter interaction. Profiting from the maximized direct enhancement of the optical field in active region by Pt plasmonic NPs resonance coupling, the increased light absorption excites abundant photogenerated carriers, which are rapidly separated by spatially coincident strong junction electric field. As a result, the resultant PD exhibits higher photocurrent and obtains an improved responsivity of 55.4 mA/W, EQE of 27 %, detectivity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.9\times 10^{{14}}$ </tex-math></inline-formula> Jones, and faster response speed under self-powered mode. The optimized optical field in active region caused by embedded Pt plasmons resonance coupling is the reason for the improvement of light absorption and photoresponsivity, which is verified by theoretical simulation. This work demonstrates for embedded plasmonic enhancement in DUV spectral region, providing an innovative pathway for the optimized design of high-sensitivity DUV PDs.