EpitaxialAlxGa1−xNfilms have been grown onc-cut sapphire substrates at 800 °C and10−2 TorrN2by pulsed laser deposition (PLD) using a KrF laser. Throughout the composition range fromx=0to 0.6, the films show epitaxial patterns in reflection high-energy electron diffraction, in agreement with the results from x-ray diffraction. The lattice constants of the films vary linearly withx. The composition dependence of the band gaps of the films deviates from linearity and bows downward. This letter reports the application of PLD to controlling the lattice constant and band gap by varying the proportion of AlN and GaN in the target mixture. ©1998 American Institute of Physics.