Effect of Hydrogen on Electrical Performance of Pt/Au β-Ga<sub>2</sub>O<sub>3</sub> (001) Schottky Barrier Diodes
Shaozhong Yue, Xuefeng Zheng, Yuehua Hong, Xiangyu Zhang, Fang Zhang, Yingzhe Wang, Ling Lv, Yanrong Cao, Xiaohua Ma, Yue Hao
Abstract
The effect of hydrogen on <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> -gallium oxide (Ga2O3) (001) Schottky barrier diode (SBD) device has been studied in this article for the first time. It was found that the electrical performance of the <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 SBDs changed significantly after hydrogen treatment, including the turn-on voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {on}}{)}$ </tex-math></inline-formula> decreased by 0.3 V and the forward ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${J}_{\text {F}}{)}$ </tex-math></inline-formula> current density increased by 28frequency-dependent conductance technique, it is found that the time constants were decreased from 0.09–0.3 to 0.06– <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.09 ~\mu \text{s}$ </tex-math></inline-formula> after hydrogen treatment. Meanwhile, the density of interface states decreases from <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.1\times 10^{{12}}$ </tex-math></inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4.2\times 10^{{12}}$ </tex-math></inline-formula> to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$7.5\times 10^{{11}}$ </tex-math></inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.6\times 10^{{12}}$ </tex-math></inline-formula> cm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{-{2}}\cdot $ </tex-math></inline-formula> eV−1 with a decrease in trap activation energy from 0.1–0.13 to 0.09–0.1 eV after hydrogen treatment. Utilizing the time-of-flight secondary ion mass spectrometry (TOF-SIMS), it is observed that the density of hydrogen at the Pt/Ga2O3 interface is increased by more than one order of magnitude for the device with hydrogen treatment. The effect of hydrogen on Pt/Au <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 SBDs can be mainly attributed to the passivation of traps by hydrogen atoms near the Pt/Ga2O3 interface.