Chlorine-based inductive coupled plasma etching ofα-Ga₂O₃

Abstract

Dry etching behavior of unintentionally-doped α-Ga 2 O 3 was investigated in a BCl 3 /Cl 2 /Ar chemistry using inductively-coupled-plasma technique. We systematically studied the impact of various etch conditions such as BCl 3 /Cl 2 /Ar gas ratio, plasma and bias powers, and chamber pressure on etch rate, surface roughness and mask selectivity of α-Ga 2 O 3 with respect to Si 3 N 4 , SiO 2 and photoresist. In contrast to GaN etching, Cl 2 was found to be far less effective than BCl 3 in etching α-Ga 2 O 3 .

Accelerated Aging Stability of β-Ga2O3–Titanium/Gold Ohmic Interfaces

“…All the four samples were then solvent-cleaned with acetone, isopropyl alcohol, and methanol and blown dry with a N 2 gun. To remove the top ∼50 nm and expose the heavily doped region, a BCl 3 -based inductively coupled plasma reactive ion etch (ICP-RIE) was applied to samples C and D. , To identify the effect of this RIE process on contact performance independent of the Si-ion implant, sample B underwent the same dry etching process. All four samples were then processed with conventional photolithography to define the circular transmission line model (CTLM) structures.…”

Photo-enhanced metal-assisted chemical etching of α-gallium oxide grown by halide vapor-phase epitaxy on a sapphire substrate and its applications

“…25 The root mean squared (RMS) roughness of the α-Ga 2 O 3 surface was observed to increase by 2.8 nm per 100 nm of etching, which is similar to the roughness change observed during conventional plasma etching (ICP). 13…”

Exploiting the Nanostructural Anisotropy of β-Ga2O3 to Demonstrate Giant Improvement in Titanium/Gold Ohmic Contacts

“…Conventional lift-off photolithography was used to define CTLM structures on top of the epi-substrates. BCl 3 -based ICP-RIE operated at a bias power of 100 W , was performed on sample II prior to the metal deposition. This removes ∼50 nm of the top layer.…”