Fabrication of micro-trench structures with high aspect ratio based on DRIE process for MEMS device applications

Abstract

The micro-trench structures with high aspect ratio based on the single crystal silicon substrate are fabricated via the deep reactive ion etching (DRIE) process at different etching patterns. The relationship between the micro-trench structures and the DRIE etching patterns is investigated by simulating and processing. The micro-trench structures are obtained to meet the requirements of some MEMS devices for special applications. The profile roughness and micro-trench structures are observed by the atomic force-microscope and the field emission scanning electron microscopy. The verticality (V) of micro-trench structures is average 0.19 in the oxygen environment. The micro-trench structures exhibit better verticality, less roughness and better stability than that of no oxygen. The scalloping effects gradually decreased and the profile becomes more and more polished.