PHOTOLUMINESCENCE AND MINORITY-CARRIER DIFFUSION LENGTH IMAGING IN SILICON AND GAAS

The correlation between the distribution of minority carrier diffusion lengths monitored using surface photovoltage measurements and the distribution of photoluminescence intensity has been investigated in silicon and III-V semiconductor materials. Photovoltage measurements have been performed using a non-contact probe and constant photon flux method at room temperature, while the scanning photoluminescence measurements have been done in the room to liquid helium temperature range. To demonstrate the combined capabilities of the two methods, assessments of a liquid phase electroepitaxial InxGa1-xAs single crystal and 450-degrees-C annealed silicon have been performed. The discussion emphasises the effects of non-uniform carbon distribution in InGaAs and oxygen-related defects in silicon.