TEM observation of the phase transition in indented GaAs

Indentations carried out with the loads of 0.0049, 0.049 and 0.098 N, respectively, on the surface of GaAs single crystal have been observed using transmission electron microscopy (TEM). The results show that plastic deformation took place in all the samples and phase transformation was induced by indentation. The microcrystal occurred beneath the 0.0049-N load indentation and the amorphous structure was formed under the 0.049-N load indentation. No obvious phase transformation was found beneath the 0.098-N load indentation. The possible mechanisms for the transformation from crystalline to the amorphous and microcrystalline structure were discussed. (C) 2002 Published by Elsevier Science B.V.