TITLE:
Temporal Evolution of Anodization Current of Porous Silicon Samples
AUTHORS:
Adriana Gutiérrez, Jairo Giraldo, Mario Enrique Rodríguez-García
KEYWORDS:
Porous Silicon; Electrochemical Etching; Anodization Current
JOURNAL NAME:
Materials Sciences and Applications,
Vol.4 No.8A,
August
14,
2013
ABSTRACT:
Temporal evolution of the anodization current of porous silicon samples was studied by means of a model of resistances connected in series that represented the temporal changes of the substrate and of the interface between the substrate and the electrolyte during the porous sample formation process. The porous samples were obtained by means of photoelectrochemical etching of (100) n-type silicon wafers with different resistivity values, all in the range of 1 - 25 Wcm. The samples were formed at room temperature in an electrolytic bath composed by a mixture of hydrofluoric acid (48%) and ethanol having a composition ratio of 1:1 in volume under potentiostatic condition (10 V and 20 V) and an etching time of 2 minutes using back illumination provided by a laser beam with a wavelength of 808 nm.