Berlin 2005 – wissenschaftliches Programm
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DS: Dünne Schichten
DS 12: Ionen-Festkörper-Wechselwirkung II
DS 12.2: Vortrag
Montag, 7. März 2005, 11:30–11:45, TU HS107
Swift heavy ion irradiation of InP: Why a thin surface layer remains crystalline? — •Andrey Kamarou, Werner Wesch, and Elke Wendler — Institut für Festkörperphysik, Universität Jena, Max-Wien-Platz 1, 07743 Jena
Irradiation of single-crystalline InP with large fluences of swift heavy ions (SHI) causes formation of amorphous layers within the depth range of dominating electronic energy loss εe. However, unlike the bulk, thin surface layers (tens of nm) remain almost undamaged. In order to amorphise also those thin crystalline surface layers (TCSL), much higher SHI fluences are necessary. Hence, two suggestions can be made: (a) either the surface acts as a powerful sink for defects generated by SHI irradiation near the surface (i.e., they move towards the surface and annihilate there), or (b) SHI energy deposition is not constant within thin surface layers.
Our results show that the existence of TCSL can not be solely due to migration of defects to the surface, but should be ascribed to εe that increases with depth in the thin surface layers. Particularly, the last feature is characteristic to SHI having the initial charge lower than the equilibrium one for the bulk. Generally, one can state the dominating influence of SHI charge state; the influence of the surface itself is less significant, but can not be ruled out completely.