In this paper, the anodization of porous silicon is explained. Porous silicon is formed through electrochemical etching. Several variable parameters are explored, garnering different results. In addition to these, a relay timer and a four point probe were fabricated to aid in the anodization process and the characterization process, respectively. Electrical characterization was done with this four point probe, which was constructed at Fort Lewis College with a cost effective setup. Anodized wafers exhibited higher resistivities than unanodized wafers. Furthermore, longer anodized wafers had more uniform anodizations. It was found that longer four point probe measurements read increased resistivities, a result that should not have been the case. This was likely caused by fluid within the pores, and as such allowed a potential application for these wafers to be used as a humidity sensor. With an applied electrical current, the fluid can evaporate, and increase the resistivity. This can be analyzed in such a way that the precipitation in the air can be monitored. These wafers can be recreated for use in electrical devices, physical filters, sensors, or other applications.
