直流电化学腐蚀法制备多孔硅的表面形貌研究

采用正交实验，直流电化学腐蚀法制备多孔硅。用原子力显微镜对表面进行观察，研究电化学腐蚀参数对其表面形貌的影响。氢氟酸浓度（CHF）升高，使临界电流密度（JPS）增大，有利于多孔硅的形成。电流密度（J）增大，多孔硅的孔隙率和孔径随之变大，而其纳米粒径将变小。腐蚀时间（t）越长，孔径越大，孔越深。

MORPHOLOGICAL STUDIES OF FOROUS SILIOCN FABRICATED BY GALVANOSTATIC ELECTROCHEMICAL ETCHING METHOD

With the orthogonal experiment,porous silicon(PS) was fabricated by galvanostatic electrochemical etching method.Surface morphology of PS was observed by Atomic Force Microscopy(AFM),and the effect of the electrochemical etching parameters on the surface morphology was studied systematically.The increased C_(HF) concentration makes the critical current density(J_(PS)) higher,which enhances the formation of PS.The current density is the main factor affecting the radius of the etched holes and the remaining silicon columns and the porosity.The higher current density makes the porosity and the radius of the etched holes and larger and the left silicon columns smaller.The anodization duration mainly affects the radius and thickness of the etched holes.The longer the anodization duration is,the thicker the PS layer and the larger of the radius of the etched holes will be.