G. Romero-Paredes, R. Peña-Sierra y C. Vázquez²Electrónica del Estado Sólido, Departamento de Ingeniería Eléctrica,² Departamento de Física.CINVESTAV-IPN, Av. IPN # 2508, 07000 México, D.F., Apdo. Postal 14-740. E-mail: gromero@email.cinvestav.mx

In this work we introduce an autocatalitic copper solution for depositing copper films on silicon and porous silicon (PS). The process is a modification of the one used for isotropic silicon etching. Highly diluted copper solutions allow depositing thin films with thickness of some nanometers.

Thin copper films can be used for reducing the contact resistance on porous silicon metallic contacts. On the other hand when the copper films are oxidized it could passivate the dangling bonds of the PS filament surface, stabilizing the PS photoluminescence.

The copper and copper oxide films on silicon were characterized by ellipsometry and resistance measurements. On porous silicon the effect of these films was evaluated by means of photoluminescence, FTIR, chemical analyze, and by current voltage characteristics of PS-Silicon structures.