Patent ID: 8603314
Filing Date: 2013-12-10
Classification: C25D,C25F,H01L,Y02E,Y02P

Abstract:
1. A method comprising: a) providing a semiconductor wafer comprising a front side comprising an oxidized emitter layer, a back side and a PN junction; b) contacting the semiconductor wafer with a composition comprising one or more sources of bifluorides, one or more fluoride salts, or mixtures thereof and one or more sources of metal ions; c) generating an electrical current in the composition; d) applying anodic current for a predetermined period of time, followed by turning the anodic current off for a predetermined period of time and repeating the cycle to form a nanoporous layer on the oxidized emitter layer of the semiconductor wafer; and e) applying cathodic current and light to deposit a metal on the nanoporous layer.