Effect of oxygen plasma treatment on the performance of recessed AlGaN/GaN Schottky barrier diodes

The treatment effect of the oxygen plasma on the performance of recessed AlGaN/GaN Schottky barrier diodes has been investigated. After the oxygen plasma treatment, the turn-on voltage and reverse leakage current are slightly changed, while the current collapse could be effectively mitigated. The X-ray photoelectron spectroscopy results suggest that a thin surface oxide layer is formed by the oxygen plasma treatment, which is responsible for the reduced current collapse. In addition, the device with oxygen plasma treatment has a relatively more inhomogeneous barrier height.

A highly stable temperature sensor based on Au/Cu/n-Si Schottky barrier diodes depending on the inner metal thickness

We have fabricated the Au/n-Si (D1), Au/Cu/n-Si (D2), Au/Cu(4nm)/n-Si (D3) and Au/Cu(2nm)/n-Si (D4) Schottky-barrier diodes (SBDs). The thickness of the Cu Schottky contact (SC) films for the D2, D3, and D4 diodes has been chosen as 100, 4 and 2 nm, respectively. We have investigated the thermal sensitivity from the voltage-temperature (V-T) characteristics of the SBDs at different current levels. The V-T measurements have been made in the temperature range from 10 K to 320 K with steps of 2 K, at the different current levels from 50 nA to 141.70 µA. The V-T curves have shown a good linearity degree for all SBDs. The slope dV/dT = α or thermal sensitivity coefficient α for each diode has decreased with increasing current level from 50 nA to 141.70 µA. But, it has been seen that the SBDs with the Cu SC have approximately the same α value as independent of metal thickness at the same current level. That is, the thermal sensitivity coefficient value has changed approximately from 2.48 mV/K at 50 nA to 1.82 at 141.70 µA for the SBDs with Cu Schottky contact as independent metal thickness. Furthermore, the α versus current level plots of the diodes have exhibited a linear behavior. The intercept α0 and slope dα/dI values of the α versus current level plots have been obtained as 2.80 mV/K and -0.0843 mV/(AK) for D2, and 2.85 mV/K and -0.092 mV/(AK) for D3 and 2.83 mV/K and -0.0876 mV/(AK) for D4. These values are very close to each other and the difference between the slope (dα/dI) values is small enough to be neglected.

Large-size (1.7 × 1.7 mm2) β-Ga2O3 field-plated trench MOS-type Schottky barrier diodes with 1.2 kV breakdown voltage and 109 high on/off current ratio

We fabricated high forward and low leakage current trench MOS-type Schottky barrier diodes (MOSSBDs) in combination with a field plate on a 12 μm thick epitaxial layer grown by halide vapor phase epitaxy on β-Ga2O3 (001) substrate. The MOSSBDs, measuring 1.7 × 1.7 mm2, exhibited a forward current of 2 A (70 A cm−2) at 2 V forward voltage and a leakage current of 5.7 × 10–10 A at −1.2 kV reverse voltage (on/off current ratio of > 109) with an ideality factor of 1.05 and wafer-level specific on-resistance of 17.1 mΩ · cm2.