Selective epitaxial growth of GaAs using dimethylgalliumchloride by multi-wafer low-pressure metal organic vapor phase epitaxy (LP-MOVPE)

Abstract

We demonstrated for the first time the selective epitaxial growth of n-GaAs using dimethylgalliumchloride (DMGaCl) by a multi-wafer LP-MOVPE system. We achieved complete selective epitaxy for the GaAs at a growth rate of more than 0.4 μm/h with an electron carrier concentration of more than 5×10 18 cm −3. The growth rate and the carrier concentration were analyzed to verify whether this process could be used for the mass-production of FET devices. The growth rate when employing DMGaCl depended less on the size of open area than in the case of a conventional trimethylgallium (TMGa) source, which is a result of the different vapor phase diffusion lengths of the used Ga-containing materials. The impurity concentrations of the selective epitaxial layers, which were measured by secondary ion mass spectrometry (SIMS), were low enough for practical FET applications.