Grating-mode-type wide-band SAW resonators for VCOs

Isobe, Aki; Hikita, M.; Asai, K.; Sumioka, A.

doi:10.1109/ultsym.1998.762110

Cited by 22 publications

(11 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to interaction between two modes, the coupling of the spurious mode grows around these values faster than far from interaction points. It is nearly zero at h/Λ about 12.5%, which agrees with previously published optimal thickness of Al electrodes [4]. With deviation of frequency or metal thickness to lower values of parameter h/Λ, it grows faster because of increasing interaction between two modes.…”

Section: Theoretical Investigation Of Two Surface Modessupporting

confidence: 90%

“…Shimizu [3] found experimentally that the Rayleigh-type mode can be minimized in 15°YX cut of LiNbO 3 with gold electrodes of optimal thickness about 4.2% Λ , where Λ is SAW wavelength at synchronous resonance condition. Isobe [4] found that with Al electrodes the same orientation provides minimum spurious mode if electrode thickness is about 12.5%Λ. Hashimoto [5] found that the optimal thickness is about 7.5%Λ when Cu is employed as electrode material.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Optimal cut of lithium niobate with suppressed Rayleigh-type mode for application in resonator SAW filters

Naumenko

Abbott²

2008

2008 IEEE Ultrasonics Symposium

View full text Add to dashboard Cite

Results of resonators constructed on rotated YX lithium niobate (LiNbO 3 ), to provide minimum coupling of the spurious Rayleigh-type mode are reported. The resonator employs non-leaky waves which result when the metal grating's electrodes are sufficiently heavy to suppress attenuation of leaky waves. The coupling of two SAW modes propagating in rotated YX cuts was estimated as function of cut angle and electrode thickness, with Al or Cu as electrode material. The optimal orientation, 19°YX for Al grating or 20°YX for Cu grating, is compared with previously reported 15°YX cut. If the electrode thickness is optimized to suppress the spurious mode, in 15°YX the coupling of this mode grows fast with variation of frequency or electrode thickness because of close proximity between the velocities of two modes. In 19°YX cut the resonance of the spurious mode is located in the middle of the interval between the resonance and anti-resonance of non-leaky SAW mode. The spurious mode is made less sensitive to variations of frequency or metal thickness and provides better performance of resonator filters. This conclusion is confirmed experimentally.

show abstract

Section: Theoretical Investigation Of Two Surface Modessupporting

confidence: 90%

Section: Introductionmentioning

confidence: 99%

Optimal cut of lithium niobate with suppressed Rayleigh-type mode for application in resonator SAW filters

Naumenko

Abbott²

2008

2008 IEEE Ultrasonics Symposium

View full text Add to dashboard Cite

show abstract

“…It has been suggested that the application of highly piezoelectric non-leaky share-horizontal (SH) type SAWs propagating under very thick gratings on YX-LiNbO 3 may be one of the candidates for the present purpose [1], [2]. For example, the authors have proposed an ultra-wideband ladder type filter with a small insertion loss [3], consisting of resonators employing SH type SAWs on Cugrating/15 • YX-LiNbO 3 structure [4]; its minimum insertion loss of less than 1 dB and extremely wide passband of 18% around 1 GHz are experimentally achieved as shown in Fig.…”

Section: Introductionmentioning

confidence: 99%

P6G-2 Synthesis of Frequency Response for Wideband SAW Ladder Type Filters

Omori

Tanaka²,

Hashimoto³

et al. 2007

2007 IEEE Ultrasonics Symposium Proceedings

View full text Add to dashboard Cite

Numerical synthesis of frequency response is discussed for a ladder type filter consisting of ultra-wideband SAW resonators on Cu-grating/15 • YX-LiNbO3 structure. For the synthesis, two parameters of each resonator, i.e., the static capacitance and resonant frequency were numerically optimised, while the capacitance ratio and figure of merit were fixed at specific values determined by substrates and grating electrodes employed. First, six-stage SAW ladder type filters having the passband width of 7 to 21% were designed. The result showed that the specified bandwidth is successfully synthesised. Next, a six-stage ladder type filter having the passband width of 8% was fabricated on Cugrating/15 • YX-LiNbO3 structure for experimental discussion. It was shown that the measured frequency response of the filter was in good agreement with the design, where some in-band spurious dips were removed by weighted dummy electrodes. By making analysis on the behaviour of resonant and anti-resonant frequencies of each resonator, it is shown that the method can be extended to the synthesis of filters having sophisticated frequency responses. The result suggested that the proposed method could become one of the powerful design tools for SAW ladder type filters with specified passband width.

show abstract

“…1 forming Al electrode fingers in a grating shape on a 15° YX-LiNbO 3 substrate. What is unique in this resonator is that a special SAW is used for which the excitation energy is trapped at the edges of the Al grating electrode fingers [8,9]. This is different from the Love-wave-type SAW in which gold electrodes with a large mass are used [5] and is unique to Al grating electrode fingers [12].…”

Section: Grating Mode and Electrode Finger Film Thicknessmentioning

confidence: 99%

“…The authors have already reported a grating-modetype SAW resonator using Al as the electrode finger material on a 15° YX-LiNbO 3 substrate [8,9]. The present resonator is realized by discovery of a special SAW in © 2001 Scripta Technica Electronics and Communications in Japan, Part 2, Vol.…”

Section: Introductionmentioning

confidence: 96%

Fabrication method for grating‐mode‐type SAW resonator used in voltage‐controlled oscillator: optimum shape for electrode fingers and investigation of accurate process techniques

Asai¹,

Hikita²,

Isobe³

et al. 2001

Electron. Comm. Jpn. Pt. II

View full text Add to dashboard Cite

SUMMARYAn optimum electrode finger shape is obtained for the grating-mode-type SAW resonator on a 15° YXLiNbO 3 with a large relative bandwidth used for a high-C/N broadband VCO. Spurious responses by Rayleigh wave need to be suppressed completely in the SAW resonator. Its impedance characteristics are extremely sensitive to the variations of electrode finger linewidth and film thickness. The specifications for the film thickness and linewidth of the electrode finger are derived by simulation and experiment. It is demonstrated that the electrode finger film thickness of h/O 0 = 0.1325 and the relative electrode finger linewidth ratio of L / L S 0.575 are standard and their deviations need to be controlled accurately in fabrication. Assuming applications to industrial wireless terminals at 170 and 420 MHz, process accuracy enhancement is discussed so that the electrode finger specifications are satisfied. In the present SAW resonator with a thick electrode finger, an antireflection film is introduced in the photoresist process. Al-Cu alloy is used for the electrode fingers to produce an excellent impedance characteristic. The VCO using the present SAW resonator satisfies the specifications of the above wireless terminals. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(9): 1120, 2001

show abstract

Grating-mode-type wide-band SAW resonators for VCOs

Cited by 22 publications

References 8 publications

Optimal cut of lithium niobate with suppressed Rayleigh-type mode for application in resonator SAW filters

Optimal cut of lithium niobate with suppressed Rayleigh-type mode for application in resonator SAW filters

P6G-2 Synthesis of Frequency Response for Wideband SAW Ladder Type Filters

Fabrication method for grating‐mode‐type SAW resonator used in voltage‐controlled oscillator: optimum shape for electrode fingers and investigation of accurate process techniques

Contact Info

Product

Resources

About