A combination of electroless and electrochemical etching methods for enhancing the uniformity of porous silicon substrate for light detection application

► A combination of electroless and electrochemical etching of silicon is introduced. ► A novel parameter called delay-time (Td) is optimized prior to applying pulsed current. ► The uniformity of fabricated porous silicon is enhanced by applying Td = 2 min. ► The optimized porous structures show a noticeable Raman shift with small FWHM, representing good crystalline quality. ► Efficient photodetectors are fabricated on nano-structured porous silicon by a combination of electroless and electrochemical etching of silicon substrate.