Niobate-tantalate thin films microwave varactors
2006 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Thin solid films, Vol. 515, no 2, 619-622 p.Article in journal (Refereed) Published
We present comparative characteristics of microwave variable capacitors (varactors) fabricated on Na0.5K0.5NbO3 (NKN), AgTa0.5Nb0.5O3 (ATN) and Ba0.5Sr0.5TiO3 (BST) ferroclectric films sintered by pulsed laser deposition technique. Two port 2 mu m finger gap coplanar waveguide interdigital capacitive (CPWIDC) structures were defined on ferroelectric films surface by a standard lift off technique. Results of the microwave on-wafer tests performed in frequency range 1 to 40 GHz have been examined with a de-embedding technique to extract device characteristics from the measured S-parameters. The frequency dispersion of capacitance was 37%, 4.3%, and 17%; the voltage tunability (200 kV/cm) 22%, 4.7%, and 22% at 20 GHz; loss tangent similar to 0.23, 0.068, and 0.137 at 20 GHz for NKN/Nd:YAlO3, ATN/Al2O3, and BST/Al2O3 films capacitors.
Place, publisher, year, edition, pages
2006. Vol. 515, no 2, 619-622 p.
ferroelectric ceramics, pulsed laser deposition, epitaxial films, pottasium sodium niobate, silver tantalate niobate, barium strontium titanate, coplanar waveguides, voltage tunable microwave devices, scattering parameters measurement
Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-6582DOI: 10.1016/j.tsf.2005.12.212ISI: 000241220600057ScopusID: 2-s2.0-33748755445OAI: oai:DiVA.org:kth-6582DiVA: diva2:11332
QC 201009062006-12-122006-12-122011-09-28Bibliographically approved