The effects of short pulsed ruby laser annealing on GaAs layers grown on Si substrates by metalorganic chemical vapor deposition have been characterized by Raman spectroscopy and double‐crystal x‐ray diffraction. After laser melting and regrowth, the stress‐released layer is formed in the near‐surface. The formation of the stress‐released layer results in the microcracking of the pulsed‐laser‐annealed GaAs surface. However, the high crystalline quality of this stress‐released layer is detected. Furthermore, when GaAs layer is overgrown on this stress‐released layer, this layer plays a role of blocking the dislocation threading into the overgrown GaAs layer.