CHARACTERIZATION OF ELECTRONIC TRANSPORT-PROPERTIES IN SEMICONDUCTORSBY SCANNING PHOTOTHERMAL MICROSCOPY

In this paper we demonstrate that a photothermal microscopy experiment can be used to determine the electronic diffusivity (or carrier mobil ity). The main difficulty lies in the fact that in order to separate t hermal and carrier diffusion, the experiment must be performed for a r elatively large distance between the pump and probe beams. Phototherma l signals are therefore rather weak and great experimental care must b e taken. Wk present and. discuss experimental results on Si.