Photoelectrochemical (PEC) etching of Ga2O3

In recent years, interest in the use of gallium oxide (Ga₂O₃) in semiconductor devices has increased due to its wide bandgap that permits device operation at high temperatures and high voltages. As the size of these devices decrease, it becomes more important to be able to produce features on the micro and nanoscale. Traditional etching (both wet and dry) have several limitations which either are unable to produce nano-features at the required scale or degrade device quality. Consequently, photoelectrochemical etching of Ga₂O₃ is of interest to researchers for its potential to produce features on the order of magnitude required while also causing minimal device degradation. Photoelectrochemical etching introduces a number of parameters that can be adjusted to control the etching process. In this work, we demonstrated photoelectrochemical etching of Ga₂O₃ by showing the effect of changing electrolyte concentration, anodic voltage, and etching time on the etching process. This etching method could be useful for a variety of applications which require complex patterning of Ga₂O₃ with high degrees of control compared to simple wet or dry etching processes.