Bulk samples can be prepared by heating indium(III) hydroxide or the nitrate, carbonate or sulfate. 
Thin films of indium oxide can be prepared by sputtering of indium targets in an argon/oxygen atmosphere. They can be used as diffusion barriers ("barrier metals") in semiconductors, e.g. to inhibit diffusion between aluminium and silicon.
Monocrystalline nanowires can be synthesized from indium oxide by laser ablation, allowing precise diameter control down to 10 nm. Field effect transistors were fabricated from those. Indium oxide nanowires can serve as sensitive and specific redox protein sensors. The sol–gel method is another way to prepare nanowires.
Indium oxide can serve as a semiconductor material, forming heterojunctions with p-InP, n-GaAs, n-Si, and other materials. A layer of indium oxide on a silicon substrate can be deposited from an indium trichloride solution, a method useful for manufacture of solar cells.