Alpha-emission channeling investigations of the lattice location of Li in Ge

[摘要] 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 [100], [110] and [211] 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.

[发布日期] 1996-09-01

[效力级别]  Proceedings Paper