2-38 GHz Broadband Compact InGaAs PIN Switches using a 3-D MMIC Technology

Compact SPST switches using an InGaAs PIN diode have been developed for broadband MMIC applications. The cut-off frequency which is a figure of merit of the InGaAs PIN diode is obtained to be 5.1 THz. Three different circuit schematics were designed to compare the switch performances. For high-performance of the InGaAs PIN switches, the bias networks and DC blocking capacitors are monolithically integrated. The InGaAs PIN switches were successfully fabricated by using a developed benzocyclobutene(BCB)-based multi-layer MMIC technology. The multi-layer structure and meandered microstrip line configuration effectively reduce the chip area of the SPST series-shunt-shunt type PIN switch to 0.92 times 0.70 mm². The good microwave performance and broadband characteristics have been achieved from the fabricated MMIC switches.