Abstract: Disclosed herein are transistor source/drain contacts, and related methods and devices. For example, in some embodiments, a transistor may include a channel and a source/drain contact, wherein the source/drain contact includes an interface material and a bulk material, the bulk material has a different material composition than the interface material, the interface material is between the bulk material and the channel, the interface material includes indium and an element different from indium, and the element is aluminum, vanadium, zirconium, magnesium, gallium, hafnium, silicon, lanthanum, tungsten, or cadmium.