Porous silicon fabrication technique for large area devices

Abstract

An improved technique applied for fabrication of porous silicon layers on silicon wafers is proposed. The main principle is the vacuum pulling and holding of the sample instead of mechanical pressing or using of special acid-proof wax. Large silicon wafers can be etched in this electrochemical cell. Porous silicon coating was ‘‘deposited’’ on as-prepared solar cells. This procedure improved the cell’s performance very significantly: we have obtained ∼30% increase in efficiency on cells with no antireflection coating.