The fundamental mechanism of H-induced exfoliation was investigated by using spectroscopic and microscopic techniques. The evolution of the internal defect structure was studied as a function of implanted H concentration and annealing temperature. It was found that the mechanism involved a number of essential components; among which H played a key role. It was shown that the chemical action of H led to the formation of (100) and (111) internal surfaces, at temperatures above 400C, via agglomeration of the initial defect structure. Molecular H was evolved at temperatures of between 200 and 400C, and was subsequently trapped in micro-voids that were bounded by the internal surfaces. This resulted in a build-up of internal pressure which, in turn, led to the observed blistering of unconstrained Si samples, or the complete layer transfer in Si wafers that were joined to a support that acted as a mechanical stiffener.

M.K.Weldon, V.E.Marsico, Y.J.Chabal, A.Agarwal, D.J.Eaglesham, J.Sapjeta, W.L.Brown, D.C.Jacobson, Y.Caudano, S.B.Christman, E.E.Chaban: Journal of Vacuum Science and Technology B, 1997, 15[4], 1065-73