High density packaging of X-band active array modules

A new high-density package design has been used to reduce the cost, weight, and size of X-band active array radars. The package used multilayer aluminum nitride (AlN) substrates, flipped monolithic microwave integrated circuit (MMIC) chips, coplanar waveguide transmission lines, and solderless fuzz button interconnects. This paper discusses the design tradeoffs, the package construction and assembly, and test results.