In this work microrelief transformation of the (001) GaAs surface due to thin Al film deposition by means of the CBE method has been observed. The growth process was monitored insitu using laser reflectometry. Investigations of samples formed, carried out using TEM-microscopy, show that one of the basic causes of the microrelief transformation is the laser assistance of metal growth. A laser with a low power is used in this work for Al layer composite control in CBE. It was found that, in spite of using a laser having a low power, it is possible to stimulate and guide the complex physical and chemical reactions between deposited Al atoms and the GaAs near-surface layer. It has been found that metal film growth with laser assistance is a non-equilibrium process. The shapes and dimensions of the grown islands depend upon the laser power.