Compact ferroelectric reflection phase shifters at X-band

Compact reflection phase shifters using thin film barium strontium titanate have been developed. X-band designs measuring less than 0.5 mm/sup 2/ are realized by using only lumped element components. The circuits are constructed monolithically, using planar spiral inductors, thin-film resistors, and parallel plate ferroelectric capacitors on a dielectric substrate. A novel low impedance transforming design is used to enhance performance. The first prototypes show promise, giving approximately 14/spl deg//dB. Further process and design improvements will increase performance.