Fluorine Plasma Treatment for AlGaN/GaN HEMT-Based Ultraviolet Photodetector With High Responsivity and High Detectivity
Kunnan Zhou, Longqiang Shan, Yuliang Zhang, De Lu, Yuanming Ma, Xing Chen, Lin‐Bao Luo, Chunyan Wu
Abstract
AlGaN/GaN high electron mobility transistor (HEMT) has attracted great attention in ultraviolet photodetectors (UVPDs) due to the ultrahigh responsivity and high photocurrent arising from the two-dimensional electron gas (2DEG) formed in the AlGaN/GaN interface. In this letter, AlGaN/GaN HEMT-based UVPD was fabricated through fluorine plasma treatment using <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{C}_{{4}}\text{F}_{{8}}$ </tex-math></inline-formula> gas. The dark current of the device was greatly lowered and the persistent photoconductivity (PPC) effect was effectively suppressed, leading to a high responsivity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${1}.{3}\times {10} ^{{4}}$ </tex-math></inline-formula> A <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{W}^{-{1}}$ </tex-math></inline-formula> and a high specific 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">${1}.{8}\times {10} ^{{15}}$ </tex-math></inline-formula> Jones. The present work provides a facile and cost-effective strategy for the fabrication of high-performance AlGaN/GaN HEMT-based UVPDs.