High Quality P-Type Mg-Doped β-Ga2O3-δ Films for Solar-Blind Photodetectors

作者：Zhou, Xin; Li, Ming; Zhang, Jinzhong^*; Shang, Liyan; Jiang, Kai; Li, Yawei; Zhu, Liangqing; Hu, Zhigao^*; Chu, Junhao

来源：IEEE Electron Device Letters, 2022, 43(4): 580-583.

DOI：10.1109/LED.2022.3151476

• Solar-blind photodetectors
• wide bandgap
• p-type Ga2O3-delta films
• pulsed laser deposition

The ((2) over bar 01)-oriented Mg-doped beta-Ga2O3-delta films were grown on (0001)-sapphire substrates by pulsed laser deposition (PLD) at various oxygen partial pressures (P-O 10-40 mTorr). The conductivity type of the as-deposited Mg-doped beta-Ga2O3-delta films is proved to be p-type according to the transfer characteristic curves of a top-gate field effect transistor (FET) and rectification curves of the Mg-doped/undoped beta-Ga2O3-delta junction. In addition, the two-terminal solar-blind photodetectors based on Mg-doped beta-Ga2O3-delta films prepared at P-O = 30 mTorr exhibite a good optoelectrical performance with a low dark current of 0.19 pA at 10 V, a high I-254nm/I-dark ratio of 1.3 x 10(4), fast rise (tau(r1 )= 0.035 s and tau(r2 )= 0.241 s) and decay (tau(r1 ) = 0.022s and tau(r2 ) = 0.238s) times. The present work indicates that the p-type Mg-doped beta-Ga(2)O(3-delta )films can be used in the third-generation ultraviolet photodetectors.