The electrical, optical properties of AlSb polycrystalline thin films deposited by magnetron co-sputtering without annealing

In order to fabricate AlSb polycrystalline thin films without post annealing, this paper studies a technology of magnetron co-sputtering onto intentionally heated substrate. It compares the structural characteristics and electrical properties of AlSb films which are deposited at different substrate temperatures. It finds that the films prepared at a substrate temperature of 450 ^\circC exhibit an enhanced grain growth with an average grain size of 21 nm and the lattice constant is 0.61562 nm that goes well with unstained lattice constant (0.61355 nm). The ln(\sigma_dark) ～1/T curves show that the conductivity activation energy is about 0.38 eV when the film is deposited at 450 ^\circC without an annealing. The transmittance and reflectance spectra show that the film deposited at 450 ^\circC has an optical band gap of 1.6 eV. These results indicate that we have prepared AlSb polycrystalline films which do not need a post annealing.