Fabrication of silicon tip array and its application in vacuum microelectronic accelerometer

A simple, low cost and high yield method for the fabrication of silicon tip array for potential use in microelectronic applications is proposed. Both anisotropic and isotropic wet chemical etching methods are studied. The etching mechanism, etching rate and the shape of silicon tip in different solutions are analyzed by scanning electron microscope (SEM). The results show that the undercutting rate is dramatically reduced because of adding I2 and KI in 40% mass fraction KOH solution, and a rocket tip on the upper part of silicon tip is obtained. The shape ofsilicon tip etched in HNA looks like Eiffel Tower, and the radius of curvature is less than 15 nm. This silicon tip array has been successfully integrated into the fabrication of vacuum microelectronic accelerometer.