Effect of Nd:YAG laser irradiation on the characteristics of porous silicon photodetector

Electrical and photoresponse properties of a Al/porous silicon/crystalline silicon/Al structure (Al/PSi/Si/Al) are investigated under irradiation of Nd:YAG laser pulses. The effect of Nd-YAG laser irradiation on the morphological and structural properties of a porous silicon layer is also demonstrated. The porous Si layer is synthesized on a single crystalline p-type Si using electrochemical etching in aqueous hydrofluoric acid at a current density of 20 mA/cm2 for a 40-min etching time. The structure of the porous layer is investigated using atomic force microscopy and optical microscopy. The electrical properties and photodetector figures of merit (responsivity, detectivity, and carrier lifetime) are found to be dependent on the laser fluence.