GISAXS Study of Hydrogen Implanted Silicon

The grazing incidence small angle X-ray scattering (GISAXS) technique was used to study monocrystalline silicon samples implanted with H-2 ions at an energy of 31 keV and to the dose of 10(16) ions/cm(2). Samples were annealed isochronally at different temperatures. Although the H depth distribution was expected to be smooth initially, nanosized features, like agglomerates of defects, have been detected. Annealing destroys this feature due to the relaxation of defects, i.e. redistribution of vacancies and hydrogen. Above 300degreesC a well defined film with highly correlated borders is formed on the edge of the layer rich in defects, whose thickness is slowly decreasing from 25 to 22 nm with increasing annealing temperature. Moreover, defects as well as hydrogen are migrating towards the surface with increasing annealing temperature, as indicated by the increase in surface roughness.