Low-cost, high-performance package for a multi-chip MMIC module

A ceramic package for a multichip monolithic microwave integrated circuit (MMIC) has been developed which consists of a multilayer ceramic frame whose layers are metallized over most of both surfaces and cofired. The frame is metallized on all sides including inner and outer walls, and metal-to-ceramic hermetically sealed. Microstrip lines and through-wall microstrips with shielded walls for the RF I/O ports are designed for 50- Omega impedance. The insertion loss of each I/O port is less than 0.5 dB up to 33 GHz, with a complementary I/O isolation in excess of 30 dB. The package also provides 1.32:1 input VSWR (voltage standing-wave ratio). A 30-GHz-band multichip MMIC amplifier incorporating four GaAs MMICs was demonstrated using this ceramic package. A maximum gain of 19 dB is achieved with 1.5:1 input VSWR across the 20.5-to-32.5-GHz band.<>