Improvement of barium strontium titanate solidly mounted resonator quality factor by reduction in electrode surface roughness

AbstractBarium strontium titanate solidly mounted resonators (SMR) were fabricated with three different acoustic Bragg reflectors (ABR) on a sapphire substrate. The three devices had ABR structures consisting of W/SiO2/W/SiO2, Mo/SiO2/Mo/SiO2, and Pt/SiO2/Pt/SiO2 respectively. The s-parameters of all three devices were measured. The results showed that the quality factor increased as a function of the material in the ABR structure. The quality factor for the devices with tungsten, molybdenum and platinum in the ABR structures are 101, 88, and 31, respectively. This investigation showed how the material in the ABR structure can contribute to the acoustic loss in the device.

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The Effect of Patterned vs. Unpatterned Acoustic Bragg Reflector on Barium Strontium Titanate Solidly Mounted Resonator

MRS Proceedings ◽

10.1557/opl.2011.1024 ◽

2011 ◽

Vol 1368 ◽

Author(s):

George N. Saddik ◽

Robert A. York

Keyword(s):

Quality Factor ◽

Strontium Titanate ◽

Barium Strontium Titanate ◽

Sapphire Substrate ◽

Bragg Reflector ◽

Bragg Reflectors ◽

Quality Factors ◽

Barium Strontium ◽

S Parameters ◽

Resonant And Antiresonant Frequencies

ABSTRACTBarium strontium titanate solidly mounted resonators were fabricated with patterned and unpatterned acoustic Bragg reflectors on a sapphire substrate. The patterned and unpatterned solidly mounted resonator devices had acoustic Bragg reflectors consisting of Pt/SiO2/Pt/SiO2. The s-parameters of both devices were measured. The results showed that the quality factor increased for the device with the patterned acoustic Bragg reflector structure. The quality factors for the devices with patterned and unpatterned acoustic Bragg reflector structures were 54 and 115 and 28 and 86, respectively at the resonant and antiresonant frequencies. This investigation shows how an unpatterened acoustic Bragg reflector can contribute to the degradation of the overall quality factor of the device.

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Physical Characterization of BST with Different (x’) Ratios

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.487.106 ◽

2014 ◽

Vol 487 ◽

pp. 106-109

Author(s):

Nurhafizah Ramli ◽

Zaliman Sauli ◽

Vithyacharan Retnasamy ◽

They Yee Chin ◽

K. Anwar ◽

...

Keyword(s):

Thin Films ◽

Surface Roughness ◽

Strontium Titanate ◽

Barium Strontium Titanate ◽

Sol Gel ◽

Force Microscopy ◽

Atomic Force ◽

Fields Of Study ◽

Barium Strontium

Nowdays Barium strontium titanate (BST) can be applied into many fields of engineering. Its properties attracted more researchers to research and apply it into many fields of study. In this work, sol-gel method of preparing barium strontium titanate (BST) has been used. This work was done with 4 different ratio of x with 4 different deposition layers. The main purpose of this work is to investigate the relation between the ratio of barium (Ba) with different deposition layer and the surface of the substrate. Atomic force microscopy (AFM) was used in whole work to investigate the crystalline structure and surface roughness of the BST thin films.

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