Rosfariza Radzali

The effect of ecthing duration on structural properties of porous Si fabricated by a new two-steps alternating current photo-assisted electrochemical etching (ACPEC) technique for MSM photodetector

This project presents a new method to fabricate porous Si using two-step Alternating Current Photo-Assisted Electrochemical Etching (ACPEC) technique. The n-type Si (111) was initially etched for a short time to form high density of etch pits and subsequently the sample was anodized in HF solution by using alternating current photo-assisted electrochemical etching (ACPEC) technique. The study aims to investigate the effect of different etching duration on the properties of porous Si. This new method of porous Si fabrication produced higher density, porosity and more uniform distribution of triangular-like pores compared to the sample etched without the initial etching. We observed that the pore size, porosity and average surface roughness were increased with etching duration. Amongst the samples, the 10 minutes of etched sample showed the maximum pore diameter and porosity. Subsequently, metal-semiconductor-metal (MSM) photodetector have been fabricated by depositing Al metal contacts on the non-porous an...