Deep Dry Etching Patterned Silicon Using GeSbSnOx Thermal Lithography Photoresist

Abstract

An innovative chemical composition GeSbSnOx is introduced as positive-type photo-resist in sub-micro scale lithography. Unlike the conventional acrylic type photo-resist, this innovative photo-resistor can overcome the diffraction limit using the thermal mode recording and leave a small hole diameter of 350 nm on the surface under this experimental condition. The effects of the reactive ion etching parameter on the silicon etching were reported. The major etching parameters include passivated time, etching time, passivation cycles, total worked backing pressure, platen power, coil power and passivation gases applied. The etched depth increased monotonically with increasing the gas pressures and the platen powers. The most important factors to reduce the reaming effect of Si etching are found to be the ratio of passivation time to etching time and the etching gas flow rate. Both etched depth and reamed width decreased with increasing the ratio of passivation time to etching time and the linear relation was observed between the etched depth and the ratio.