The effect of temperature gradient on the variation of surface topography and reflectivity of anisotropically etched silicon wafers

Abstract

A novel approach to wet etching of silicon wafers (100) is described in this study. Homogenous organized surface structures were prepared by the utilization of self-organized flow in the etching solution (Bénard-Marangoni thermocapillar instability). The driving force behind this process is a temperature gradient generated by the etching apparatus exclusively constructed for this research. The influences of temperature gradients (1–20 K) and etching time (20–55 min) were studied, with the potassium hydroxide/isopropyl alcohol etching solution. Obtained results indicate that self-organized flow can be utilized for specific and rapid etching, which allows significant variation of the topography and reflectivity of the silicon wafer surface textured in this way.