Description:
<jats:p>InSb films have been grown by rf sputtering on cleaved BaF2, CaF2, NaCl, and NaI substrates in addition to polished and annealed (111) -oriented CaF2 wafers. Growth temperatures investigated ranged from 40 to 300 °C, while deposition rates R ranged from 20 to 450 Å/min. The epitaxial temperature for InSb was found to decrease with decreasing deposition rate and decreasing film-substrate lattice mismatch. Stoichiometric single-crystal films were grown on cleaved BaF2 substrates at temperatures as low as 150 °C at R=20 Å/min. Polycrystalline films grown on cleaved CaF2 exhibited a greater degree of preferred orientation than films on polished and annealed CaF2, but the grain size was always less for a given growth temperature. The maximum grain size was related to the film thickness. The electrical properties of 2000-Å-thick polycrystalline InSb films on polished and annealed CaF2 were investigated. The room-temperature electron carrier concentration and Hall mobility of films grown at 300 °C were 4×1017 cm−3 and 200 cm2/V sec, respectively. The dominant charge-scattering mechanism was identified as potential-barrier scattering at either high- or low-angle grain boundaries depending on the grain size of the film.</jats:p>