Title :
A new high performance phase shifter using Ba/sub x/Sr/sub 1-x/TiO3 thin films
Author :
Acikel, Baki ; Taylor, Troy R. ; Hansen, Peter J. ; Speck, James S. ; York, Robert A.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Santa Barbara, CA, USA
fDate :
7/1/2002 12:00:00 AM
Abstract :
In this paper, a new device topology has been proposed to implement parallel plate capacitors using Ba/sub x/Sr/sub 1-x/TiO/sub 3/ (BST) thin films. The device layout utilizes a single parallel capacitor and minimizes conductor losses in the base electrode. The new design simplifies the monolithic process and overcomes the problems associated with electrode patterning. An X-band 180/spl deg/ phase shifter has been implemented using the new device design. The circuit provided 240/spl deg/ phase shift with an insertion loss of only 3 dB at 10 GHz at room temperature. We have shown a figure of merit 93/spl deg//dB at 6.3 GHz and 87/spl deg//dB at 8.5 GHz. To our knowledge, these are the best figure of merit results reported in the literature for distributed phase shifters implemented using BST films at room temperature.
Keywords :
antenna phased arrays; barium compounds; ferroelectric capacitors; ferroelectric thin films; microwave phase shifters; strontium compounds; 10 GHz; 240/spl deg/ phase shift; 3 dB; 6.3 GHz; 8.5 GHz; Ba/sub x/Sr/sub 1-x/TiO/sub 3/; Ba/sub x/Sr/sub 1-x/TiO/sub 3/ thin films; X-band 180/spl deg/ phase shifter; base electrode conductor losses; device topology; distributed phase shifters; electrode patterning; ferroelectric varactors; figure of merit; high performance phase shifter; insertion loss; monolithic process; parallel plate capacitors; phase arrays; voltage controlled delay lines; Binary search trees; Capacitors; Conductors; Electrodes; Phase shifters; Strontium; Temperature; Thin film circuits; Thin film devices; Topology;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2002.801129
