A ruggedly packaged D-Band GaAs Gunn diode with hot electron injection suitable for volume manufacture

GaAs Gunn diodes optimized for use in second harmonic mode at 125 GHz have been fabricated with hot electron injection based on a novel step-graded Al_xGa_(1-x)As launcher. Testing was performed after encapsulation in rugged, hermetically sealed packages using a similar process to that performed for volume manufacture of devices for the automotive industry. RF power levels up to 40 mW at 121.5 GHz in second harmonic mode have been obtained with an efficiency of 1.45% and an average frequency drift of 0.5 MHz/degC. Unlike the majority of state-of-the-art unpackaged devices reported in the literature which rely on diamond heat sinking, these packaged devices incorporate an integral gold heatsink, and so offer lower unit cost, increased manufacturability, and ease of integration into real-world systems.