Y. Kang et J. Jorne, DISSOLUTION MECHANISM FOR P-SI DURING POROUS SILICON FORMATION, Journal of the Electrochemical Society, 144(9), 1997, pp. 3104-3111
The anodic polarizations of p-Si with various doping levels in concent
rated HF solution have been studied. A theoretical model, based on the
potential distribution during anodization, is developed. The computed
polarization curves fit the experimental data quite well. Both the sp
ace charge region and the Helmholtz interface control the anodic behav
ior of p-Si. The effect of the Helmholtz interface becomes dominant as
the doping level increases. The most likely dissolution mechanism dur
ing porous silicon formation involves the capture of two holes to form
Si(II), which further reacts with protons to produce Si(IV) and H-2 g
as.