Abstract: Highly crystalline quality AlN thin films were successfully grown on Ti_0.8Al_0.2N/TiN-buffered
p-Si(100) substrates by pulsed laser deposition (laser source: KrF). X-ray diffraction (XRD) and reflective high energy electron diffraction (RHEED)
were employed to characterize the as-grown films. The results show that AlN thin films are (001) oriented and grown with 2D layer growth mode. The growth modes of
thin films rely on the kinds of buffer layers: AlN thin films on Si wafers or MgO/Si substrates are 3D island grown; whereas those on Ti_0.8Al_0.2N/TiN/Si
substrates are 2D layer grown. In addition, the laser energy density has considerable effects on the crystalline quality of AlN thin films: over high
energy leads to rough surface and big particles. The partial nitrogen pressure can make AlN thin films (100) orientation instead of (001) orientation.

Key words: pulsed laser deposition, aluminium nitride thin film, buffer layer