Large area BST thin films for microwave applications deposited by pulsed laser ablation

Author(s)

C. V. Varanasi, University of Dayton
K. D. Leedy, Air Force Research Laboratory, Sensors Directorate, Wright-Patterson Air Force Base
D. H. Tomich, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base
Guru Subramanyam, University of DaytonFollow

Document Type

Article

Publication Date

3-2-2009

Publication Source

Thin Solid Films

Abstract

Large area Ba_{1 − x}Sr_xTiO₃ (BST) thin films with x = 0.4 or x = 0.5 were deposited on 75 mm diameter Si wafers in a pulsed laser deposition (PLD) chamber enabling full-wafer device fabrication using standard lithography. The deposition conditions were re-optimized for large PLD chambers to obtain uniform film thickness, grain size, crystal structure, orientation, and dielectric properties of BST films. X-ray diffraction and microstructural analyses on the BST films grown on Pt/Au/Ti electrodes deposited on SiO₂/Si wafers revealed films with (110) preferred orientation with a grain size < 100 nm. An area map of the thickness and crystal orientation of a BST film deposited on SiO₂/Si wafer also showed (110) preferred orientation with a film thickness variation < 6%. Large area BST films were found to have a high dielectric tunability of 76% at an electric field of 400 kV/cm and dielectric loss tangent below 0.03 at microwave frequencies up to 20 GHz and a commutation quality factor of ~ 4200.

Inclusive pages

2878–2881

ISBN/ISSN

0040-6090

Publisher

Elsevier ScienceDirect

Volume

517

Peer Reviewed

yes

Issue

9

Keywords

Physical vapor deposition; Ferroelectric properties;Laser ablation; Oxides

eCommons Citation

Varanasi, C. V.; Leedy, K. D.; Tomich, D. H.; and Subramanyam, Guru, "Large area BST thin films for microwave applications deposited by pulsed laser ablation" (2009). Electrical and Computer Engineering Faculty Publications. 22.
https://ecommons.udayton.edu/ece_fac_pub/22