Low resistance Ti/Au contacts to amorphous gallium indium zinc oxides

We report on low-resistance Ti (50 nm)/Au (80 nm) contacts to amorphous gallium indium zinc oxides (a-GIZO). The specific contact resistances obtained using the transmission line method were as low as 2.85×10−5 Ω cm2 when annealed at 500 °C for 1 min in N2 ambient. This could be attributed to the combined effects of structural relaxation of a-GIZO films at elevated temperatures, causing drastic increases in both electron concentration and Hall mobility, and to interfacial reactions between Ti/Au and a-GIZO layers producing oxygen vacancies near the surface.