Dresden 2011 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 44: Poster Session I
HL 44.22: Poster
Tuesday, March 15, 2011, 18:00–21:00, P3
Structural modification of SHI irradiated amorphous Ge layers — •Tobias Steinbach1, Claudia S. Schnohr1, Leandro L. Araujo2, Raquel Giulian2, David J. Sprouster2, Mark C. Ridgway2, Daniel Severin3, Markus Bender3, Christina Trautmann3, and Werner Wesch1 — 1Institute of Solid State Physics, Friedrich Schiller University Jena — 2Department of Electronic Materials Engineering, Australian National University, Canberra — 3GSI Helmholtz Centre for Heavy Ion Research GmbH
During SHI irradiation of amorphous Ge a strong volume expansion of the amorphous layer accompanied by an enhanced plastic flow process was observed. To study the effect of high electronic energy deposition єe on a-Ge layers in more detail samples were irradiated at RT and LT with Au-ions having high energies in the range of several hundred MeV. In order to quantify the swelling of the sample one half was masked to distinguish the irradiated from the unirradiated reference. We demonstrate for all used irradiation conditions that a strong swelling of the irradiated areas can be observed, which depends linearly on the ion fluence as well as on єe. XSEM revealed the transformation of the a-Ge layer into a porous structure with irregularly shaped voids thus establishing that swelling was a consequence of void formation. Moreover, an electronic energy deposition threshold has been estimated, at which the swelling, i.e. the formation of voids, begins. Furthermore, we report on the early stages of void formation in a-Ge by means of SAXS and TEM investigations, which demonstrates that voids are formed due to the imperfect resolidification of molten ion tracks.