Air-Bridge Electron-Beam Lithography for Coplanar Millimeter Wave Circuits

Abstract

ABSTRACTIn the development of air bridges for low capacitance crossovers, resists of 3–6μm thickness a e needed, which calls for special alignment techniques. A technique has been developed for an air bridge tec nology, which is realized entirely by electron beam lithography. Such an all-electron-beam technique for sub-micron devices and ultrahigh frequency circuits, results in a fast turn-around-time in the development of integrated circuits.Gold plated air bridges with 20 to 120 pm span, 5–60 μm width, 2.6 pm height, and 2–4 μm thickness, were realized on GaAs and InP.