東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Novel RF filter structures: Acoustic...

Kulkarni, Vinay.

Linked to FindBook

Google Book

Amazon

博客來

Novel RF filter structures: Acoustically coupled piezoelectric thin films.

Record Type:	Language materials, printed : Monograph/item
Title/Author:	Novel RF filter structures: Acoustically coupled piezoelectric thin films./
Author:	Kulkarni, Vinay.
Description:	147 p.
Notes:	Adviser: Kanti Prasad.
Contained By:	Dissertation Abstracts International67-06B.
Subject:	Engineering, Electronics and Electrical. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3221068
ISBN:	9780542744679

Novel RF filter structures: Acoustically coupled piezoelectric thin films.
Kulkarni, Vinay.

Novel RF filter structures: Acoustically coupled piezoelectric thin films. - 147 p.

Adviser: Kanti Prasad.

Thesis (D.Eng.)--University of Massachusetts Lowell, 2006.

This thesis investigates methods to understand and improve electromechanical coupling by proper choice of electrode materials, device impedance matching, device symmetries, and beneficial use of external components like inductors.

ISBN: 9780542744679Subjects--Topical Terms:

626636
Engineering, Electronics and Electrical.

Novel RF filter structures: Acoustically coupled piezoelectric thin films.
LDR:03900nam 2200325 a 45 001 965269
005 20110906
008 110906s2006 eng d
020 $a 9780542744679
035 $a (UnM)AAI3221068
035 $a AAI3221068
040 $a UnM $c UnM
100 1 $a Kulkarni, Vinay. $3 1288046
245 1 0 $a Novel RF filter structures: Acoustically coupled piezoelectric thin films.
300 $a 147 p.
500 $a Adviser: Kanti Prasad.
500 $a Source: Dissertation Abstracts International, Volume: 67-06, Section: B, page: 3335.
502 $a Thesis (D.Eng.)--University of Massachusetts Lowell, 2006.
520 $a This thesis investigates methods to understand and improve electromechanical coupling by proper choice of electrode materials, device impedance matching, device symmetries, and beneficial use of external components like inductors.
520 $a Frequency selection devices, such as filters, are used to manipulate different RF bands, at widely varying frequencies in all wireless communication devices. Thin film "Piezoelectric Materials" offer great properties that can be engineered with other materials to achieve RF filtering.
520 $a In this thesis work, a Stacked Crystal Filter (SCF) is designed, fabricated and characterized. In an SCF, two piezoelectric films are vertically mounted on each other and are separated by a thin metal electrode. The SCF works on the principle of generating and transferring acoustic energy from one piezoelectric film to another at a particular range of frequencies where the structure is resonant. Simplistically, electrical energy is converted into mechanical by the input piezoelectric film, is transferred to the output piezoelectric film, which converts this mechanical energy back to electrical.
520 $a The electromechanical coupling determines the amount of energy that can be converted between electromagnetic and mechanical within a single piezoelectric film. In addition, the acoustic coupling between the two piezoelectric films determines the mechanical energy that can be transferred between them. More generally, all aspects of the electromechanical coupling in the device play important roles in determining filter center frequency, loss, and bandwidth characteristics.
520 $a Fabrication of SCF is complicated because it involves fabrication of multiple piezoelectric films. These piezoelectric films are mounted on an Acoustic Mirror to prevent loss of acoustic energy into the substrate. The acoustic mirror also serves in suppressing unwanted modes of vibration. The acoustic mirror was made up of three layers of silicon dioxide and two layers of an alloy, of titanium-tungsten. Layout of various SCF structures and process flow to fabricate these devices is presented. The center frequency was chosen as 2 GHz.
520 $a The test results of the fabricated devices are presented. On-wafer measurements were first done and compared against the model. The discrepancies between the modeled and measured were due to lower piezoelectric coupling of top piezoelectric film compared to the bottom, inaccuracies in film thickness, incorrect film parameter values such as speed and density, and formation unwanted parasitics in the structures. The model and measured data were then matched by making necessary changes to the coupling coefficient of top piezoelectric film, aluminum nitride thickness, Q of all the materials and accounting of parasitics into the model. External inductors were then connected and the increase in the filter bandwidth was shown. Another SCF was built on a different mirror which suppressed unwanted modes of vibration.
590 $a School code: 0111.
650 4 $a Engineering, Electronics and Electrical. $3 626636
690 $a 0544
710 2 0 $a University of Massachusetts Lowell. $3 1017839
773 0 $t Dissertation Abstracts International $g 67-06B.
790 $a 0111
790 1 0 $a Prasad, Kanti, $e advisor
791 $a D.Eng.
792 $a 2006
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3221068