Metal contacts to p-type crystalline CuInSe2

Bilayers of metal contacts were deposited on p-type monocrystalline copper indium diselenide (CuInSe2) and the resistance between two contacts were measured to find low resistance metal contacts on crystalline CuInSe2. The first metal layer was Ni, Pt, Se, or Te and the second metal layer was Au, Ag, Al or Cu. It was observed that the resistance reduced when the surface of crystalline CuInSe2 were etched before metal deposition with a solution containing H2SO4 (1 %, w/w) and CrO3 (1 %, w/w). It was confirmed that the resistance increases after heat- treatments at high temperature. The stability of the metal contacts in room air was estimated from the resistance measured for a period of over 20 days.