In this study, we investigated the effect of substrate temperature on the change in structural and morphological properties
of thin film Gallium Arsenide (GaAs) deposited by pulsed laser deposition (PLD) on Silicon (Si) substrate. The growths
were conducted at different substrate temperatures (25º C - 600º C). X-ray Diffraction (XRD), Atomic Force Microscopy
(AFM) and Scanning Electron Microscopy (SEM) were used to study the crystal structure and surface quality of the
films. It was observed that the films were increasingly more crystalline in the (111) orientation and also larger in crystal
grain size with increase in substrate temperature 285º C and above. The deposited GaAs films on Si were smooth, dense
and free of voids, pinholes and cracks for a wide range of temperature.