Influence of high pressure and temperature on defect structure of silicon crystals implanted with N or Si ions

(111) oriented Fz-Si crystals were implanted with N+ or Si+ at 150 keV energy to a dose of 2x1016 cm-2. After implantation the samples were treated at a high temperature (up to 1400 K) under hydrostatic argon pressure (up to 1.1 GPa) for 1-5 h. Structural properties of Si:N and Si:Si before and after the treatment were investigated by high-resolution X-ray diffraction, synchrotron topography, transmission electron microscopy and photoluminescence methods. The structural properties of Si:N and Si:Si treated under hydrostatic pressure at 1270 K are different. A buried layer of uniform thickness with smooth interface was formed in Si:N under HP=1.1 GPa; the buried layer/Si interface becomes less smooth with rising treatment time. The shape of interference fringes and their changing distance at rocking curves are explained as an effect of nitrogen diffusion to the buried layer during the treatment. For the treated Si:Si samples, the observed strain changes are related to the out-diffusion of interstitial silicon atoms from the implanted layer to the sample surface and to creation of numerous extended defects near the implanted atoms range. Prolonged treatment (for 5 h) at 1.1 GPa and 1400 K results in creation of dislocations for Si:N while for Si:Si samples the structure of treated samples is more complex, involving also creation of amorphous-like surface film