Swift heavy ion irradiation of amorphous silicon

It is well established that swift heavy ion irradiation of glasses leads to irreversible, non-saturating, macroscopic deformation due to the ion hammering effect. Because amorphous silicon is structurally different from the dense metallic silicon liquid, it has not been considered to be a glass and believed to exhibit a melting transition. Consequently, the deformation yield is supposed to be opposite in sign compared to that of glasses. In this paper, the effects of swift heavy ion irradiation of amorphous silicon have been studied as a function of electronic energy deposition, sample temperature, ion fluence and ion incident angle. It will be shown that amorphous silicon not only flows plastically in the same way as glasses, providing experimental evidence for a glass transition, but also shows dramatic swelling for non-perpendicular irradiation at room temperature using high ion fluences. (c) 2005 Elsevier B.V. All rights reserved.