Epoxy bond and stop-etch (EBASE) technique enabling backside processing of (Al)GaAs heterostructures

The epoxy bond and stop-etch (EBASE) technique enables both the frontside and the backside processing of very thin (3000Å) GaAs/AlGaAs epitaxial layer structures. Using this technique, a conventionally processed epitaxial layer structure is inverted and epoxied to a new host substrate. The original substrate is removed leaving only the original epitaxial structure expoxied to the host substrate. The exposed backside of the epitaxial structure may then be processed. Because the structures fabricated using this technique are so thin, mesas, Schottky gates, and ohmic contacts may be defined in close proximity both above and below the active device layers.