Reactive Ion Etching of Through‐the‐Wafer via Connections for Contacts to GaAs FET's

Abstract

Through‐the‐wafer via connections can provide low impedance contacts for FET's which significantly improve device characteristics. In this paper, we describe the use of a simple, thick, positive resist mask together with reactive ion etching in low pressure mixtures. This process provides controlled via profiles suitable for connections through 100 μm thick substrates. The use of this process in the fabrication of a monolithic distributed amplifier resulted in a significant improvement in gain.