A wafer-level interposer based microwave circuit and system integration technology

A wafer-scale microwave system and circuit integration method has been developed that allows the embedding of multiple semiconductor dice having varied function and material into a compact chip-scale module. This circuit integration technology includes low loss planar transmission line interconnects and integrated precision thin film resistors, capacitors and inductors; all of these structures are embedded in a micromachined silicon interposer. To demonstrate this interposer-based monolithic microwave integrated circuit (iMMIC) technology a Class-A Ku-band power amplifier has been designed and fabricated utilizing a discrete Triquint 1.2 mm X 0.35 µm pHEMT. A compact single stage amplifier produced 1 Watt of saturated output power at 14 GHz with a drain efficiency of 42.9 %, and 7.1 dB power gain. Wafer-scale micro-lithographic processing as well as selection of known-good-die for integration, will improve yield and reduced cost compared to current state-of-the-art hybrid technology. In this paper, we discuss architecture, design methodology, and the results of our demonstrated power amplifier in this new technology.