Observation of phase-locking and phase-transition of pores in silicon electrochemistry

In this work, via anodization of n-type silicon specimens pre-textured with different patterns, phase-transition of pores induced by varied HF concentrations and phase-locking of pores imposed by predefined nuclei were evidenced. Based on the analysis of scanning electron microscope (SEM) micrographs and current-voltage curves, the competition between physical and chemical elements was found to be crucial to understand the observations. Not least, our results indicate strongly that pore density can act independently as a function of the initial morphology of sample surface. Electric-field effect as well as current-burst-model (CBM) was employed to interpret the underlying mechanism.