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In this work, bottom-Schottky-structure InGaZnOx (IGZO) Schottky barrier diodes (SBDs) with sputtered PtOx anodes were fabricated and annealed in oxygen at different temperatures. Critical parameters and negative bias stress (NBS) stability of SBDs with different annealing temperatures are investigated. With the annealing temperature increases, the barrier height and rectification ratio of the SBDs exhibited a rising-then-declining trend, while the ideality factor slightly increased until 200 °C. The SBDs show up overall reliability except for a leakage current rising trend under light, which can be attributed to free electron generation from the ionized oxygen vacancy. Among all the SBDs, the 175 °C annealed ones exhibited the best overall performance, including a high barrier height of 0.89 eV, an ideality factor of 1.14, and a large rectification ratio of over 108. Compared to the initial SBDs, the annealed ones showed up great improvement in NBS stability except for the 200 °C annealed ones, which was permanently degraded and not able to recover to original states. According to experimental result analysis and IGZO material characteristics, a stability model based on the subgap trap transition from V O 2 + to VO and new V O 2 + creation was proposed, which applies to both the short-term and long-term NBS tests. The results above demonstrate that oxygen annealing at appropriate temperature is an effective method to improve both device performance and NBS stability for PtOx–IGZO SBDs. [ABSTRACT FROM AUTHOR]

Herein, high‐performance enhancement‐mode (E‐mode) β‐Ga2O3 metal‐oxide‐semiconductor field‐effect transistors (MOSFETs) are achieved on Si‐doped homoepitaxial films. Oxygen annealing (OA) treatment under the gate region is used to effectively exhaust the channel electron, resulting in the normally off operation of the device. The threshold voltage, defined as that at the drain current of 0.1 mA mm−1, for the fabricated device is extracted to be 4.1 V. Moreover, double source‐connected field plates are used to suppress the peak electric fields in both Ga2O3 channel and SiNx passivation layer. The fabricated β‐Ga2O3 MOSFETs with gate‐to‐drain distance (Lgd) of 17 μm exhibit a record high breakdown voltage over 3000 V. It is shown that the OA treatment is a new way to obtain high‐performance E‐mode β‐Ga2O3 power MOSFETs. [ABSTRACT FROM AUTHOR]

In this letter, trench-gate metal–oxide–semiconductor field-effect transistors on (010) $\beta $ -Ga2O3 epitaxial layer are fabricated. Enhancement mode is achieved by the gate-recess process, through thoroughly depleting the $\beta $ -Ga2O3 channel to get a positive threshold voltage. For the first time, by using a dynamic parameter test system, the Ga2O3 MOSFET with 2- $\mu \text{m}$ gate length is characterized to present short switching time, including turn-on time ($\textit {t}_{ \mathrm{\scriptscriptstyle ON}}$) of 28.6 ns and turn-off time ($\textit {t}_{ \mathrm{\scriptscriptstyle OFF}}$) of 94.0 ns. In addition, OFF-state interelectrode parasitic capacitances, including input capacitance ($\textit {C}_{\text {iss}}$) of 37 pF/mm, output capacitance ($\textit {C}_{\text {oss}}$) of 42 pF/mm, and reverse transfer capacitance ($\textit {C}_{\text {rss}}$) of 14 pF/mm are also obtained, which can account for the high switching speed. The static and dynamic switching properties of the trench-gate device show the potential of $\beta $ -Ga2O3 MOSFET for the high-speed switching applications. [ABSTRACT FROM AUTHOR]

An enhancement-mode $\beta $ -Ga2O3 metal–oxide–semiconductor field-effect solar-blind phototransistor on Si-doped homoepitaxial film grown by molecular beam epitaxy is demonstrated in this letter. Gate-recess process was employed to fully deplete the Ga2O3 channel to achieve positive threshold voltage ${V}_{{\textsf {th}}}$ (7 V), which broadens the operating range of the solar-blind phototransistor. The dark current of about 0.7 pA is extremely low. Under 254-nm light illumination of 63 $\mu \text{W}$ /cm2, the change of drain current reaches more than 6 orders of magnitude. Record high detectivity of 1.3 $\boldsymbol {\times }\,\,10^{{\textsf {16}}}$ Jones and photo-to-dark current ratio of $1.1\,\,{\boldsymbol {\times }}\,\,10^{{\textsf {6}}}$ are obtained, respectively. In addition, the rise and decay time are as short as 100 and 30 ms, respectively. High responsivity of $3\,\,\boldsymbol {\times }\,\, 10^{{\textsf {3}}}$ A/W and external quantum efficiency of $1.5\,\,\boldsymbol {\times }\,\,10^{{\textsf {6}}}$ % are also achieved with apparent solar-blind photodetection. [ABSTRACT FROM AUTHOR]