Frequency adjusting method for surface sound wave device and electronic apparatus
A surface acoustic wave and frequency adjustment technology, applied in circuits, electrical components, electric solid devices, etc., can solve problems such as poor operation, and achieve the effect of easy frequency adjustment, prevention of frequency fluctuation, and low center frequency
Inactive Publication Date: 2004-07-07
SEIKO EPSON CORP
View PDF5 Cites 3 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0046] Hereinafter, embodiments of the present invention will be described with reference to the drawings. figure 1 (a) A perspective view showing a schematic structure of a surface acoustic wave device a to which the frequency adjustment method of the present invention is applied. figure 1 (b) is along figure 1 (a) Cross-sectional view of line A-A. The surface acoustic wave device a as figure 1 As shown, there are: a quartz substrate 1; an IDT electrode 2 formed on the main plane of the quartz substrate 1; and reflector electrodes 3a, 3b.
[0047] exist figure 1 Among them, t is the thickness of the quartz substrate 1 , P is the pitch of the IDT electrodes 2 , λ is the wavelength of the IDT, and h is the thickness of the IDT electrodes 2 . Here, the quartz substrate 1 is cut out so that quasi-longitudinal wave type leaky surface acoustic waves can be excited. The quartz substrate 1 has a predetermined thickness t for propagating quasi-longitudinal type leaky surface acou...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention provides a surface acoustic wave device capable of precisely controlling a frequency, of reducing changes in the center frequency with the lapse of time after controlling the frequency, and of performing a stable operation for a long time. The thickness of an IDT electrode formed on a quartz substrate is set to be slightly larger than the desired thickness so that the center frequency is slightly lower than the desired frequency. Next, a voltage is applied to the IDT electrode and the center frequency is measured. At this time, the measured center frequency is slightly lower than the desired frequency. The rear surface of the quartz substrate is etched while checking the measured center frequency. As a result, the measured center frequency gradually increases and approaches the desired frequency by etching the rear surface of the quartz substrate. Further, the rear surface of the quartz substrate is continuously etched until the center frequency is the desired frequency. The etching is stopped at the point of time where the measured center frequency is the desired frequency.
Description
technical field [0001] The present invention relates to a frequency adjustment method of a surface acoustic wave device, and electronic equipment using the surface acoustic wave device adjusted by the frequency adjustment method. Background technique [0002] Patent Document 1: JP-A-2000-156620 [0003] Patent Document 2: JP-A-2002-33633 [0004] Patent Document 3: JP-A-63-305604 [0005] Patent Document 4: JP-A-3-19406 [0006] Patent Document 5: Japanese Unexamined Patent Publication No. 9-162691 [0007] Surface acoustic wave devices are circuit elements that convert electrical signals into surface waves for signal processing, and are widely used as filters and resonators. In general, conversion and inverse conversion from electrical signals to surface waves are performed by providing electrodes made of conductive films called IDT electrodes on piezoelectric elastic substrates (piezoelectric substrates). The characteristics of the surface acoustic wave device depend ...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Applications(China)
IPC IPC(8): H03B5/30H03H3/08H03H3/10H03H9/02H03H9/05H03H9/25H03H9/64
CPCH03H9/0547Y10T29/42H03H9/1071H03H9/0585H03H9/25H03H9/02622H03H3/10H03H9/059H01L2224/16225H01L2224/48091H01L2224/48465H01L2224/73265H01L2924/10158H01L2224/14H01L2924/00014H01L2924/00H01L2224/0401
Inventor 押尾政宏
Owner SEIKO EPSON CORP