Robert Actis

Miniature 3D micro-machined solid state power amplifiers

In this work, a rectangular coaxial transmission line based power amplifier is discussed. This transmission line is created by sequential photolithography and plating processes, resulting in a very wide band, dispersion-less transmission medium which includes integrated passive components. This approach yields a number of advantages over conventional microstrip circuits. This 3D micro-machining technology, called PolystrataTM technology, in which the circuit is the package, and the package is the circuit, enables one other important and far reaching advantage.

Micro-coaxial lines for active hybrid-monolithic circuits

This paper discusses fundamental properties of rectangular micro-coaxial lines fabricated in the PolyStrata™ process for broadband applications from 2–20 GHz. The possible impedance ranges for coaxial lines implemented with both five and eleven Cu layers are discussed and compared with measured results for the lowest impedance (8Ω) line. Power handling and thermal properties of these miniature lines are analyzed and measured. A 50Ω line with outer conductor cross-section of 600µm by 400µm is experimentally shown to handle 53W at 2:5GHz with a 10% duty cycle. Integration with active components is investigated and a 1–10GHz measurement of a GaN 50 MMIC amplifier shows minimal performance degradation relative to on-wafer measurements.

Broadband SDLVA, SGA, SDGVGA, and vector modulator elements for Intelligent RF Microsystems

Design and performance of state of the art wideband MMICs for Intelligent RF Microsystems are described. These include a SDLVA with the widest reported bandwidth of 5 to 20 GHz, an SGA with DC to greater than 20 GHz frequency response, a four bit 5 to 16 GHz SDGVGA and a 256 state vector modulator covering 6 to 16 GHz.