Depth profiling of the recombination activity of defects measured by temperature-dependent cross-sectional EBIC

The recombination activity of crystal defects was studied in the temperature range 80 - 300 K along cross-sections of cleaved multicrystalline silicon wafers (Silso((R))). A decrease of the Electron-Beam-Induced Current (EBIC) contrast from the sample surfaces down to a depth of about 100 mum is found after hydrogen treatment of 1 hour at 310 degreesC for both grain boundaries and intragrain dislocations. Depending on the initial activity of the defects, the effect of hydrogen passivation is best visible at intermediate temperatures of 160 - 250 K. The density of deep recombination levels in the vicinity of dislocations and the degree of the passivation are estimated based on recent model calculations of the temperature dependence of the EBIC contrast.