Surface Microstructure of Monocrystalline Silicon Anisotropically Etched with Sodium Carbonate and Sodium Bicarbonate Solutions

The surface microstructure fabrication of monocrystalline silicon by anisotropic etching with sodium carbonate and sodium bicarbonate solutions have been studied in this paper. The microstructure fabrication process has been evaluated in terms of the surface morphology size, etching condition and uniformity. The experiments show that with the solution temperature changing, the average size of microstructure varies from 0.62 μm to 1.42 μm. Similarly, with the etching time increasing from 10 min to 40 min, the average size of microstructure varies from 0.62 μm to 1.12 μm. On the basis of our experiments, it is concluded that the optimized condition is 24 wt% Na2CO3, 4 wt% NaHCO3, 90 °C and 30 min. Under optimum conditions, the silicon wafers surface exhibit a lower average size of 0.62 μm and the microstructures are uniform and continuous. It is hoped that it may lead to an increase in the microfabrication of manufacturing industry. Therefore, this promising technique provides an alternative way for the microstructure fabrication of monocrystalline silicon in the industrial production.