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Interplay between thin film ferroelectric composition, microstructure and microwave phase shifter performance
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Mueller, Carl H. Miranda, Felix A. Alterovitz, Samuel A. Romanofsky, Robert R. VanKeuls, Frederick W. |
| Copyright Year | 2003 |
| Description | One of the keys to successfully incorporating ferroelectric films into Ku-band (12 to 18 GHz) phase shifters is to establish the composition, microstructure, and thickness required to meet the tuning needs, and tailor the film properties to meet these needs. Optimal performance is obtained when the film composition and device design are such that the device performance is limited by odd mode dielectric losses, and these losses are minimized as much as possible while still maintaining adequate tunability. The parameters required to maintain device performance will vary slightly depending on composition, but we can conclude that the best tuning-to-loss figures of merit (K-factor) are obtained when there is minimal variation between the in-plane and out-of-plane lattice parameters, and the full-width half maximum values of the BSTO (002) peaks are less than approximately 0.04 deg. We have observed that for phase shifters in which the ferroelectric crystalline quality and thickness are almost identical, higher losses are observed in films with higher BaISr ratios. The best performance was observed in phase shifters with Ba:Sr = 30:70. The superiority of this composition was attributed to several interacting factors: the B a: Sr ratio was such that the Curie temperature (180 K) was far removed from room temperature, the crystalline quality of the film was excellent, and there was virtually no difference between the inplane and out-of-plane lattice parameters of the film. |
| File Size | 1135641 |
| Page Count | 12 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20030014587 |
| Archival Resource Key | ark:/13960/t4tj3g60g |
| Language | English |
| Publisher Date | 2003-01-01 |
| Access Restriction | Open |
| Subject Keyword | Space Communications, Spacecraft Communications, Command And Tracking Thin Films Phase Shift Circuits Ferroelectricity Adaptive Filters Crystallinity Microstructure Room Temperature Microwaves Tuning Curie Temperature Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
