High resolution InP via holes for millimeter wave device applications

Abstract

A Cl/sub 2/:HBr:BCl/sub 3/:Ar-based reactive ion etch process capable of producing high resolution via holes in InP has been developed. Tapered sidewall profiles are obtained using this process as a result of controlled photoresist mask erosion at an optimized etch condition. To demonstrate feasibility of this process for millimeter wave device applications, single-doped AlInAs/GaInAs/InP HEMTs with individually grounded source finger vias have been fabricated.