This book explain the conditions in forming porous silicon and we compare the differences on porous formation using alternating current (AC) and direct current (DC) conditions.The purpose of porous is to change energy gap and surface area of silicon substrate. By making porous on silicon substrate, the photodetector device will become more efficient than the normal silicon substrate. The basic idea of metal-semiconductor-metal photodetector based porous silicon is to reduce the light reflection in order to enhance the light sensitivity and on the other hand to enhance the effects of the...