ABSTRACTOperations on biological living cells and molecular devices have driven
research towards implementation of high-aspect-ratio nano-needles. However,
current nano-needle fabrication is complicated to control the sizes and
angles. In this work, we develop a simple method to fabricate repeatable and
integrated circuit (IC)-compatible sharp silicon nano-needles based on boron
etch-stop in tetramethyl ammonium hydroxide (TMAH) solutions, and the needle
angles can be accurately controlled. An analytical model is proposed to
efficiently predict the needle sizes and explain the etching evolution of
silicon nano-needles.
Oscillating high-aspect-ratio monolithic silicon nanoneedle array enables efficient delivery of functional bio-macromolecules into living cells