Koh etching of silicon

In this research, a series of comparative etching experiments on silicon wafers have been carried out using potassium hydroxide (KOH) for different experimental etching conditions for concentration, temperature and time on (100) orientation p-type silicon wafers. Besides the basic etching conditions, the position of the immersed wafer also has unpredictable effect on the etching process. This may be attributed to the relative contact position between the surface of the immersed wafer and the flow patterns of the stirred etching solution. The surface morphology analysis indicates that the specific position of the wafer, with respect to the flow of the etchant, can lead to a higher quality of uniformly rough (100) crystal face. The lowest reflectivity of etched sample is determined by using reflectivity measurements. The study reveals that, besides conventional etching conditions, the etching positions, which can be easily disregarded, are also potential conditions that have significant influence on the etching results; this may become a principal condition for etching of silicon by KOH