The effect of a thin sample on the extended defect evolution in Si~+ implanted Si

摘要

The annealing kinetics of implant damage in Si~+ implanted Si has been investigated using in-situ and ex-situ annealing of transmission electron microscopy (TEM) samples prepared prior to annealing. The defect evolution at 800 deg C was studied for a Si wafer implanted with Si~+ at 100keV to a dose of 2x10~(14) cm~(-2). This implant was above the sub-threshold loop formation threshold allowing one to study simultaneously the {311} defect dissolution and dislocation loop nucleation and growth. In order to study the effect on the defect evolution of using a thin sample for an in-situ annealing experiment, a pair of samples, one thick and one thinned into a TEM sample, were annealed in a furnace simultaneously. It was found that the presence of a second surface 2000A below the implant damage did not affect the extended defect evolution. For the insitu annealing study it was found that the {311} dissolution process and sub-threshold dislocation loop formation process was not affected by the TEM electron beam at 160kV as long as an 800 deg C furnace pre-anneal was done prior to in-situ annealing. The dissolution rate of the {311} defects was used to confirm the TEM holder furnace temperature. The results of both the in-situ the {311} defects is released during the 311 dissolution process and 30percent comes to reside in dislocation loops. Thus, the loops appear to contain a significant fraction of the total interstitial concentration introduced by the implant.