Alpha-emission channeling investigations of the lattice location of Li in Ge
Wahl, Ulrich Jahn, SG Restle, M Ronning, C Quintel, H BharuthRam, K Hofsass, H
Elsevier science bv
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms vol:118 issue:1-4 pages:76-81
The alpha-emission channeling and blocking technique is a direct method for lattice site determination of radioactive atoms in single crystals. Position-sensitive detection of emitted alpha-particles provides an efficient means of carrying out such experiments at very low doses (10(10)-10(11) cm(-2) implanted probe atoms per spectrum), Comparison of the experimental data with Monte Carlo simulations of complete two-dimensional channeling patterns (e,g. +/-2 degrees around ,  and  axes, which also includes all relevant planar directions) allows for straightforward identification and quantitative determination of occupied lattice sites, while at the same time the energy spectrum of emitted alpha-particles gives information on the probe atom depth distribution. We illustrate this for the case of ion implanted Li-8 (t(1/2) - 0.8 s) in Ge, where we identify mainly tetrahedral Li at room temperature, and bond-centered Li at slightly elevated temperature.