AlN films with c-axis orientation and thermal conductivity characteristics were deposited by using Pulsed Laser Deposition and the films were characterized by changing the deposition conditions. In particular, we investigated the optimal conditions for the application of a heat sinking plane AlN thin film. Epitaxial AlN films were deposited on sapphire ($c-Al_2O_3$) single crystals by pulsed laser deposition (PLD) with an AlN target. AlN films were deposited at a fixed pressure of $2{ imes}10^{-5}$ Torr, while the substrate temperature was varied from 500 to $700^{circ}C$. According to the experimental results of the growth temperature of the thin film, AlN thin films were confirmed with a highly c-axis orientation, maximum grain size, and high thermal conductivity at $650^{circ}C$. The thermal conductivity of the AlN thin film was found to increase compared to bulk AlN near the band gap value of 6.2 eV.