Demonstration of Surface Treatment for $\beta-\text{Ga}_{2}\mathrm{O}_{3}$ Schottky Barrier Diode with High Breakdown Voltage and Low Specific On-Resistance

In this work, the influence of different surface treatments on the breakdown voltage (BV) and the specific on-state resistance$(R_{on,sp})$of the beta-phase gallium oxide$(\beta-\text{Ga}2\mathrm{O}_{3})$Schottky barrier diodes (SBD) is investigated. The results show that after fast inductively coupled plasma (ICP) etching, slow ICP etching and piranha treatment, the unreliable surface of$\beta-\text{Ga}2\mathrm{O}_{3}$can be effectively removed with small surface roughness and little co-products, thus increasing BV from 141 V to 724 V and reducing$R_{on,sp}$from 5.1$\mathrm{m}\Omega\cdot \text{cm}^{2}$to 1.2$\mathrm{m}\Omega\cdot \text{cm}^{2}$. Consequently, the results validate the effectiveness of the surface treatments and can provide guidance for device process optimization.