Micro-fabrication of crystalline silicon by controlled alkali etching

AFM is used for sliding and forming silicon dioxide as a cover on the silicon wafer surface (1 0 0) in ambient atmosphere. The silicon dioxide layer (mask) is made through reaction of silicon and oxygen in the atmosphere during the cutting process. Then the silicon wafer samples are etched in alkaline solutions and micro-convex profile (length×width: 5 μm×5 μm, 10 μm×10 μm) is formed. As a result of the anisotropic behavior of single crystalline silicon, the etching rates in alkaline solutions depend greatly on the various crystal planes. Effect of etching conditions such as etching temperature and time as well as KOH concentrations of the alkaline solutions on the external appearance, etching rates and height of the micro-protuberances has been studied.