Methods for selective dry etching gallium oxide

Exemplary methods of etching gallium oxide from a semiconductor substrate may include flowing a first reagent in a substrate processing region housing the semiconductor substrate. The first reagent may include HX. X may be at least one of fluorine, chlorine, and bromine. The semiconductor substrate may include an exposed region of gallium oxide. Fluorinating the exposed region of gallium oxide may form a gallium halide and H2O. The methods may include flowing a second reagent in the substrate processing region. The second reagent may be at least one of trimethylgallium, tin acetylacetonate, tetramethylsilane, and trimethyltin chloride. The second reagent may promote a ligand exchange where a methyl group may be transferred to the gallium halide to form a volatile Me2GaY or Me3Ga. Y may be at least one of fluorine, chlorine, and bromine from the second reagent. The methods may include recessing a surface of the gallium oxide.