AFM Characterization of PS Prepared in Different Concentration of Hydrofluoric Acid

Abstract

The effect of HF concentration on the surface structure of porous silicon (PS) was carefully investigated by the AFM characterization. The results showed that no pores were present on PS surface which was prepared under the higher concentration of HF (10%). However, the pores were gradually visible with the HF concentration reduction. The main pores diameter was about 100 nm, when the concentration is 5.71%. The data of surface roughness and the main height distribution of the “hill” both showed an increase with the reduction of concentration, from 6.39 nm increase to 16.9 nm and from 30 nm increase to 90 nm, respectively, which implied that the pores were better exposed under the lower HF concentration.

Porous Silicon Fabrication and Surface Cracking Behavior Research Based on Anodic Electrochemical Etching▴

“…Effect of etching time on cracking behavior of PSi was investigated under various etching duration of 15, 25, 40, and 60 min., respectively. A constant etching current density was used at 15 mA cm −2 , and HF concentration was fixed at 5.71% [38]. Cross‐sectional SEM images of PSi prepared under various etching time were presented in Figure 3.…”