Porosification Analysis on the Effect of Resistivity Dependence on N-Type Pulsed Porous Silicon

Abstract

A set of n-type porous silicon (PS) layers were fabricated by photoelectrochemical etching using direct current (DC) and pulse current (PC) techniques. The study aims to compare the effect of different resistivity (5 Ω and 10 Ω) on the formation of the PS structure. The samples were etched in a solution of HF:C2H6O with a composition ratio of 1:4. The etching process were done for 30 minutes with the current density of J = 10 mA/cm2. In the time of PC etching process, the current was supplied through a pulse generator with 14 ms cycle time (T) which the on time (Ton) set to 10 ms and pause time (Toff) set to 4 ms respectively. The samples were then being characterized in terms of surface morphology by using FESEM, AFM and XRD. Through the FESEM results, it can be seen that sample with 10 Ω resistivity which using PC form a more homogeneous structure of pores as compared to other samples.