High performance mixer diode

High performance passivated GaAs schottky barrier diodes having an excellent diode n-factor (<1. 10) and a high zero bias cutoff frequency (700 GHz) were developed. Large plated gold bumps supported by thick polyimide allows one to make contact to a small cross-shaped schottky junction area with extremely low parasitic capacitance and inductance. This leads to lower conversion loss and wider bandwidth than can be achieved with conventional planar or beam lead devices. When the diode was used in a single-ended image and sum-enhanced microstrip mixer operating at an rf frequency of 12 GHz and an IF of 550 MHz, a conversion loss of 2.4 dB was achieved with 4 mW of power applied to the diode.