Low-temperature reordering in partially amorphized Si crystals

The annealing behavior of the damage produced in Si single crystals by 150 keV Au implants at ∼2×1013 ions/cm2 and at substrate temperatures of 77 K (LN2T) and 300 K, room temperature (RT), has been investigated. The annealing kinetics has been studied in the temperature range between 493 and 623 K and for times up to 2 h. Data have demonstrated that, at a fixed temperature some damage anneals out fast and then a saturation occurs for both the LN2T and RT-damaged samples. This behavior has been tentatively interpreted assuming that the damage is mainly composed by amorphous-like material and that reordering is initiated at preferential growth sites present at nonplanar crystal-amorphous interfaces.