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This article innovatively uses pulsed metal-organic chemical vapor deposition technology to optimize the quality of β-Ga2O3 thin films on (−201) β-Ga2O3 homo-substrate using indium pulse-assisted technology. The results demonstrate that the pulsed indium-assisted method, when compared with the traditional indium-assisted method, effectively suppresses the desorption of Ga2O, enhances the flatness of the β-Ga2O3 film, and reduces the surface roughness from 34.8 to 0.98 nm. The optimized single crystalline β-Ga2O3 film was grown with pulsed-indium, and the full width at half maximum of x-ray diffraction rocking curve was 30.42 arc sec, smaller than that of the continuous indium β-Ga2O3 (56.1 arc sec). In combination with the x-ray photoelectron spectroscopy O1s split-peak fitting analysis, the relative content of oxygen vacancies in the film was significantly reduced by pulsed indium-assisted method. The Hall mobility of films assisted by pulsed-indium is approximately 14 times higher than that of films assisted by traditional indium. The pulsed indium technology provides an idea for homoepitaxial growth of high-quality β-Ga2O3 films. [ABSTRACT FROM AUTHOR]

In this paper, the radiation effect of gamma irradiation (60Co) on the Au/Ni/β-Ga2O3 vertical Schottky barrier diodes (SBDs) was investigated for total doses of about 1 Mrad (Si). The SBDs were characterized by current density–voltage (J–V) and capacitance–voltage (C–V) measurements. Compared with original β-Ga2O3 SBDs, it was found that Schottky barrier height Φb increases from 1.08 to 1.12 eV, the ideality factor n decreases from 1.07 to 1.02, and the specific on-resistance Ron,sp decreases from 3.34 to 2.95 mΩ·cm2 for the irradiated β-Ga2O3 SBDs. In addition, the carrier concentration calculated from the C–V measurements increases slightly after gamma irradiation. The temperature-dependent current–voltage characteristics and conductance-frequency measurements indicate that the Schottky contact interface of β-Ga2O3 SBDs had been slightly improved after irradiation. These results suggest that β-Ga2O3 SBDs have high intrinsic gamma irradiation hardness. [ABSTRACT FROM AUTHOR]

In this work, we demonstrated the enhancement mode (E-mode) β-Ga2O3 metal–oxide–semiconductor field-effect transistor (MOSFET) by introducing a hybrid floating gate (HFG) structure. This E-mode Ga2O3 MOSFET featured the highest VTH of 9.03 V and the highest maximum current ID of 70.0 mA/mm among the reported lateral normally off β-Ga2O3 MOSFETs. Meanwhile, a breakdown voltage of 834 V, a specific on-resistance RON,sp of 19.3 mΩ·cm2, and a sub-threshold swing SS of 87 mV/dec were achieved simultaneously. In addition, VTH shifted by only 9.9% after applying a gate stress of 25 V for 105 s. These findings provide a promising path for the development of enhancement-mode Ga2O3 power devices by incorporating a charge-storage structure. [ABSTRACT FROM AUTHOR]

In this work, an enhancement-mode (E-mode) β-Ga2O3 metal-oxide-semiconductor field-effect transistor (MOSFET) has been achieved by incorporating a laminated-ferroelectric charge storage gate (L-FeG) structure [Al2O3/HfO2/Al2O3/Hf0.5Zr0.5O2 (HZO) of 10/5/2/16 nm]. The band diagram between L-FeG dielectrics (Al2O3, HfO2, and HZO) and β-Ga2O3 was determined by x-ray photoelectron spectroscopy. After applying a gate pulse with an intensity of +18 V and width of 1 ms, the saturation current of the E-mode device was measured to be 23.2 mA/mm, which shows a negligible current reduction compared to that of 22.1 mA/mm in a depletion- (D-) mode device. In addition, the threshold voltage (VTH) is only shifted by 2.76% and 2.18%, respectively, after applying the gate stress and gate-drain stress of 15 V for 104 s. Meanwhile, a high breakdown voltage of 2142 V and specific on-resistance (RON,sp) of 23.84 mΩ·cm2 were also achieved, which correspond to a state-of-art high power figure of merit of 192.5 MW/cm2, showing the great potential of combing the ferroelectric gate stack and lateral Ga2O3 MOSFET as next generation power devices. [ABSTRACT FROM AUTHOR]

We have demonstrated the epitaxial growth of a β-(Al0.08Ga0.92)2O3 film on a β-Ga2O3 (010) substrate through pulsed laser deposition. The temperature-dependent electrical characteristics of Au/Ni/β-(Al0.08Ga0.92)2O3 Schottky diodes were investigated in the temperature range of 300–573 K, using thermionic emission theory to calculate the Schottky diode parameters. The barrier height ϕb was found to increase, while the ideality factor n and the series resistance Rs were found to decrease with increasing temperatures. The calculated values of ϕb and n varied from 0.81 eV and 2.29 at 300 K to 1.02 eV and 1.65 at 573 K. The temperature-dependent I-V characteristics of the Schottky diode have shown the Gaussian distribution, yielding a mean barrier height of 1.23 eV and a standard deviation of 0.147 V, respectively. A modified Richardson plot of ln ( I s / T 2 ) − ( q 2 σ s 2 / 2 k 2 T 2 ) versus q/2kT gives ϕ b 0 ¯ and A* as 1.24 eV and 44.3 A cm−2 K−2, showing the promise of Ni/β-(AlGa)2O3 as a Schottky diode rectifier. [ABSTRACT FROM AUTHOR]