PHOTOLUMINESCENCE AND SURFACE MORPHOLOGY OF NANOSTRUCTURED POROUS SILICON

摘要

Nanostructured porous silicon was prepared using electrochemical etching method under constant currents. We have studied the photoluminescence (PL) and surface morphology of two samples PS1 and PS2 prepared at current density 30 and 50mA/cm2under 2min. etching time respectively. Photoluminescence study showed that the electronic band gap can be tuned from 1.97 and 1.93 with respect to the applied current density. The atomic force microscopy (AFM) investigation showed the surface roughness and pyramid like hillocks. However, the granular structure in a columnar shape is confirmed by scanning electron microscope (SEM).