We have developed a new way of the constant growth technique to conserve a grating height of vertical-stacked V-groove AlGaAs/GaAs multilayer on submicron gratings up to 1.5 mum thickness by a low-pressure metalorganic chemical vapor deposition. The V-shaped GaAs buffer, grown on thermally deformed submicron gratings, has an important role in overcoming mass transport effects by recovering the deformed grating profile from sinusoidal to V-shaped. The low AlAs mole fraction is Favorable to preserve the grating height up to a greater thickness. The constant growth technique is an important step to realize complex optoelectronic devices such as one-step grown distributed feedback lasers and two-dimensional photonic crystals.