Patent US2476066A successfully refreshed from Google Patents.
US4642505A
Expired / Lapsed
US
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Laser trimming monolithic crystal filters to frequency
Assignee: CTS Corp
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Filing: 1984-03-05
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Granted: 1987-02-10
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Expires: 2004-03-05
Abstract
Abstract An improved method of adjusting piezoelectric devices to frequency by particularized laser trimming is disclosed. The laser removes a single contiguous area in the center of the electrodes to appropriately increase the individual resonator frequency without significantly degrading the filter "Q". In an AT-cut monolithic crystal filter, the particularized laser trimmed area can be positioned such on the face of the electrodes to simultaneously control frequency and bandwidth. This method can be substituted for the more cumbersome process of frequency adjustment by vapor deposition to provide a rapid inexpensive technique for monolithic crystal filter manufacture.
Inventors
- 👤 Aristotelis S. Arvanitis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:45
CPC Classifications
H; H03; H03H; H03H3/00; H03H3/007; H03H3/02; H03H3/04; Y; Y10; Y10T; Y10T29/00; Y10T29/42
Claims Analysis
Total Claims: 58
Claim 1
Independent Claim
90 words
An improved method of adjusting the resonant frequency of a piezoelectric device having a plurality of electrodes positioned on opposing surfaces of a crystal wafer to form at least one piezoelectric resonator, including the steps of: laser machining the electrode material from the respective resonator electrode to adjust the frequency of said resonator to a desired value, said laser machining being effected in the approximate geometric center of said electrode in a single contiguous area manner, whereby the Q of said piezoelectric device is minimally affected by said laser machining.
Claim 2
Dependent Claim
90 words
An improved method of adjusting the resonant frequency of a piezoelectric device having a plurality of electrodes positioned on opposing surfaces of a crystal wafer to form at least one piezoelectric resonator, including the steps of: laser machining the electrode material from the respective resonator electrode to adjust the frequency of said resonator to a desired value, said laser machining being effected in the approximate geometric center of said electrode in a single contiguous area manner, whereby the Q of said piezoelectric device is minimally affected by said laser machining.
Claim 3
Dependent Claim
27 words
The method as described in claim 1, wherein said single contiguous area manner of laser machining is generated by an outwardly spiralling path of partially overlapping holes.
Claim 4
Dependent Claim
21 words
The method as described in claim 2, wherein said lasered holes are partially overlapping in both the X and Y directions.
Claim 5
Dependent Claim
17 words
The method as described in claim 3, wherein said lasered holes are approximately one mil in diameter.
Claim 6
Dependent Claim
33 words
The method as described in claim 1, wherein said laser machining removes electrode material from both electrodes positioned on opposing sides of said crystal wafer substantially simultaneously with a single laser machining operation.
Claim 7
Dependent Claim
18 words
The method as described in claim 1, wherein said piezeoelectric device crystal wafer is comprised of AT-cut quartz.
Claim 8
Dependent Claim
16 words
The method as described in claim 1, wherein said piezeoelectric device is a monolithic crystal filter.
Claim 9
Dependent Claim
109 words
An improved method of adjusting the resonant frequency of a monolithic crystal filter device having a plurality of electrodes positioned on opposing surfaces of a crystal wafer to form at least two acoustically-coupled piezoelectric resonators, including the steps of: laser machining the electrode material from the respective resonator electrode to adjust the frequency of said resonator to a desired value, said laser machining being effected in a single contiguous area manner but at a location shifted from the geometric center of said electrode so as to alter the inter-resonator coupling between said resonators, whereby the Q of said monolithic crystal filter device is minimally affected by said laser machining.
Claim 10
Dependent Claim
109 words
An improved method of adjusting the resonant frequency of a monolithic crystal filter device having a plurality of electrodes positioned on opposing surfaces of a crystal wafer to form at least two acoustically-coupled piezoelectric resonators, including the steps of: laser machining the electrode material from the respective resonator electrode to adjust the frequency of said resonator to a desired value, said laser machining being effected in a single contiguous area manner but at a location shifted from the geometric center of said electrode so as to alter the inter-resonator coupling between said resonators, whereby the Q of said monolithic crystal filter device is minimally affected by said laser machining.
Claim 11
Dependent Claim
30 words
The method as described in claim 8, wherein said laser machining being effected at a location shifted toward the inter-resonator gap to narrow the bandwidth of said monolithic crystal filter.
Claim 12
Dependent Claim
31 words
The method as described in claim 8, wherein said laser machining being affected at a location shifted away from the inter-resonator gap to widen the bandwidth of said monolithic crystal filter.
Claim 13
Dependent Claim
27 words
The method as described in claim 8, wherein said single contiguous area manner of laser machining is generated by an outwardly spiralling path of partially overlapping holes.
Claim 14
Dependent Claim
21 words
The method as described in claim 11, wherein said lasered holes are partially overlapping in both the X and Y directions.
Claim 15
Dependent Claim
17 words
The method as described in claim 12, wherein said lasered holes are approximately one mil in diameter.
Claim 16
Dependent Claim
33 words
The method as described in claim 8, wherein said laser machining removes electrode material from both electrodes positioned on opposing sides of said crystal wafer substantially simultaneously with a single laser machining operation.
Claim 17
Dependent Claim
19 words
The method as described in claim 8, wherein said monolithic crystal filter device wafer is comprised of AT-cut quartz.
Claim 18
Dependent Claim
128 words
An improved method of adjusting the frequency difference between a predetermined pair of acoustically-coupled resonators of a monolithic crystal filter device having a singular common ground electrode covering the inter-resonator coupling area on one surface of a crystal wafer and individual electrodes on the opposing surface, including the steps of: laser machining the electrode material from the respective resonator electrode to adjust the frequency of said resonator to a desired value, subsequently vapor depositing material onto said singular common ground electrode to adjust the center frequency of said monolithic crystal filter device, said laser machining being effected in the approximate geometric center of said individual electrode in a single contiguous area manner, whereby the Q of said monolithic crystal filter device is minimally affected by said laser machining.
Claim 19
Dependent Claim
128 words
An improved method of adjusting the frequency difference between a predetermined pair of acoustically-coupled resonators of a monolithic crystal filter device having a singular common ground electrode covering the inter-resonator coupling area on one surface of a crystal wafer and individual electrodes on the opposing surface, including the steps of: laser machining the electrode material from the respective resonator electrode to adjust the frequency of said resonator to a desired value, subsequently vapor depositing material onto said singular common ground electrode to adjust the center frequency of said monolithic crystal filter device, said laser machining being effected in the approximate geometric center of said individual electrode in a single contiguous area manner, whereby the Q of said monolithic crystal filter device is minimally affected by said laser machining.
Claim 20
Dependent Claim
33 words
The method as described in claim 16, wherein said laser machining being effected upon the lower frequency resonator electrode of said predetermined resonator pair to decrease the frequency difference between said resonator pair.
Claim 21
Dependent Claim
33 words
The method as described in claim 16, wherein said laser machining being effected upon the higher frequency resonator electrode of said predetermined resonator pair to increase the frequency difference between said resonator pair.
Claim 22
Dependent Claim
27 words
The method as described in claim 16, wherein said single contiguous area manner of laser machining is generated by an outwardly spiralling path of partially overlapping holes.
Claim 23
Dependent Claim
21 words
The method as described in claim 19, wherein said lasered holes are partially overlapping in both the X and Y directions.
Claim 24
Dependent Claim
17 words
The method as described in claim 20, wherein said lasered holes are approximately one mil in diameter.
Claim 25
Dependent Claim
33 words
The method as described in claim 16, wherein said laser machining removes electrode material from both electrodes positioned on opposing sides of said crystal wafer substantially simultaneously with a single laser machining operation.
Claim 26
Dependent Claim
19 words
The method as described in claim 16, wherein said monolithic crystal filter device wafer is comprised of AT-cut quartz.
Claim 27
Dependent Claim
87 words
A piezoelectric device adjusted to a desired frequency having minimally affected Q, comprising: a piezoelectric crystal wafer having two opposing major surfaces, at least two electrodes, each of which is positioned on opposing surfaces in an overlying relationship to form at least one piezoelectric resonator, at least one electrode having a single contiguous area in the approximate geometric center of said electrode, said contiguous area comprised of a plurality of partially-overlapping laser-machined holes, whereby the Q of said piezoelectric device is minimally affected by said laser machining.
Claim 28
Dependent Claim
87 words
A piezoelectric device adjusted to a desired frequency having minimally affected Q, comprising: a piezoelectric crystal wafer having two opposing major surfaces, at least two electrodes, each of which is positioned on opposing surfaces in an overlying relationship to form at least one piezoelectric resonator, at least one electrode having a single contiguous area in the approximate geometric center of said electrode, said contiguous area comprised of a plurality of partially-overlapping laser-machined holes, whereby the Q of said piezoelectric device is minimally affected by said laser machining.
Claim 29
Dependent Claim
27 words
A piezoelectric device as described in claim 24, wherein said contiguous area has the maximum amount of electrode material removed from within the perimeter of said area.
Claim 30
Dependent Claim
22 words
A piezoelectric device as described in claim 24, wherein said laser-machined holes are partially overlapping in both the X and Y directions.
Claim 31
Dependent Claim
18 words
A piezoelectric device as described in claim 24, wherein said laser-machined holes are approximately one mil in diameter.
Claim 32
Dependent Claim
38 words
A piezoelectric device as described in claim 24, wherein both electrodes positioned on opposing sides of said crystal wafer each have said single contiguous area of approximately the same dimensions in approximately the same location on each electrode.
Claim 33
Dependent Claim
19 words
A piezoelectric device as described in claim 24, wherein said piezeoelectric device crystal wafer is comprised of AT-cut quartz.
Claim 34
Dependent Claim
17 words
A piezoelectric device as described in claim 24, wherein said piezeoelectric device is a monolithic crystal filter.
Claim 35
Dependent Claim
91 words
A monolithic crystal filter device adjusted to a desired frequency having minimally affected Q, comprising: a piezoelectric crystal wafer having two opposing major surfaces, a plurality of electrodes, each positioned on said opposing surfaces in an overlying relationship to form at least two acoustically-coupled piezoelectric resonators, at least one electrode having a single contiguous area at a location shifted from the geometric center of said electrode, said contiguous area comprised of a plurality of partially-overlapping laser-machined holes, whereby the inter-resonator coupling between said resonators has been altered by said laser machining.
Claim 36
Dependent Claim
91 words
A monolithic crystal filter device adjusted to a desired frequency having minimally affected Q, comprising: a piezoelectric crystal wafer having two opposing major surfaces, a plurality of electrodes, each positioned on said opposing surfaces in an overlying relationship to form at least two acoustically-coupled piezoelectric resonators, at least one electrode having a single contiguous area at a location shifted from the geometric center of said electrode, said contiguous area comprised of a plurality of partially-overlapping laser-machined holes, whereby the inter-resonator coupling between said resonators has been altered by said laser machining.
Claim 37
Dependent Claim
35 words
A monolithic crystal filter device as described in claim 31, wherein said contiguous areas are positioned at a location shifted toward the inter-resonator gap so as to narrow the bandwidth of said monolithic crystal filter.
Claim 38
Dependent Claim
35 words
A monolithic crystal filter device as described in claim 31, wherein said contiguous areas are positioned at a location shifted away from inter-resonator gap so as to widen the bandwidth of said monolithic crystal filter.
Claim 39
Dependent Claim
29 words
A monolithic crystal filter device as described in claim 31, wherein said contiguous area has the maximum amount of electrode material removed from within the perimeter of said area.
Claim 40
Dependent Claim
24 words
A monolithic crystal filter device as described in claim 31, wherein said laser-machined holes are partially overlapping in both the X and Y directions.
Claim 41
Dependent Claim
20 words
A monolithic crystal filter device as described in claim 31, wherein said laser-machined holes are approximately one mil in diameter.
Claim 42
Dependent Claim
40 words
A monolithic crystal filter device as described in claim 31, wherein both electrodes positioned on opposing sides of said crystal wafer each have said single contiguous area of approximately the same dimensions in approximately the same location on each electrode.
Claim 43
Dependent Claim
22 words
A monolithic crystal filter device as described in claim 31, wherein said monolithic crystal filter device wafer is comprised of AT-cut quartz.
Claim 44
Dependent Claim
131 words
A monolithic crystal filter device adjusted to a desired frequency having minimally affected Q, comprising: a piezoelectric crystal wafer having two opposing major surfaces, a singular common ground electrode covering the inter-resonator coupling area on one surface of said crystal wafer, at least two individual electrodes, both positioned on the opposing surface of said wafer in an overlying relationship to said common ground electrode to form a pair of acoustically-coupled piezoelectric resonators, at least one individual electrode having a single contiguous area in the approximate geometric center of said individual electrode, said contiguous area comprised of a plurality of partially-overlapping laser-machined holes, and an additional layer of electrode material vapor-deposited onto said singular common ground electrode, whereby the frequency difference between said resonator pairs has been altered by said laser machining.
Claim 45
Dependent Claim
131 words
A monolithic crystal filter device adjusted to a desired frequency having minimally affected Q, comprising: a piezoelectric crystal wafer having two opposing major surfaces, a singular common ground electrode covering the inter-resonator coupling area on one surface of said crystal wafer, at least two individual electrodes, both positioned on the opposing surface of said wafer in an overlying relationship to said common ground electrode to form a pair of acoustically-coupled piezoelectric resonators, at least one individual electrode having a single contiguous area in the approximate geometric center of said individual electrode, said contiguous area comprised of a plurality of partially-overlapping laser-machined holes, and an additional layer of electrode material vapor-deposited onto said singular common ground electrode, whereby the frequency difference between said resonator pairs has been altered by said laser machining.
Claim 46
Dependent Claim
45 words
A monolithic crystal filter device as described in claim 39, wherein said individual electrode having said contiguous area is part of the lower frequency resonator of a predetermined resonator pair, whereby the frequency difference between said resonator pair has been decreased by said laser machining.
Claim 47
Dependent Claim
45 words
A monolithic crystal filter device as described in claim 39, wherein said individual electrode having said contiguous area is part of the higher frequency resonator of a predetermined resonator pair, whereby the frequency difference between said resonator pair has been increased by said laser machining.
Claim 48
Dependent Claim
29 words
A monolithic crystal filter device as described in claim 39, wherein said contiguous area has the maximum amount of electrode material removed from within the perimeter of said area.
Claim 49
Dependent Claim
24 words
A monolithic crystal filter device as described in claim 39, wherein said laser-machined holes are partially overlapping in both the X and Y directions.
Claim 50
Dependent Claim
20 words
A monolithic crystal filter device as described in claim 39, wherein said laser-machined holes are approximately one mil in diameter.
Claim 51
Dependent Claim
40 words
A monolithic crystal filter device as described in claim 39, wherein both electrodes positioned on opposing sides of said crystal wafer each have said single contiguous area of approximately the same dimensions in approximately the same location on each electrode.
Claim 52
Dependent Claim
22 words
A monolithic crystal filter device as described in claim 39, wherein said monolithic crystal filter device wafer is comprised of AT-cut quartz.
Claim 53
Dependent Claim
20 words
The method as described in claim 1, wherein the frequency of said resonator is adjusted on the order of kilohertz.
Claim 54
Dependent Claim
20 words
The method as described in claim 8, wherein the frequency of said resonator is adjusted on the order of kilohertz.
Claim 55
Dependent Claim
20 words
The method as described in claim 16, wherein the frequency of said resonator is adjusted on the order of kilohertz.
Claim 56
Dependent Claim
29 words
A piezoelectric device as described in claim 24, wherein said single contiguous area is dimensioned such that the frequency of said device is changed on the order of kilohertz.
Claim 57
Dependent Claim
31 words
A monolithic crystal filter device as described in claim 31, wherein said single contiguous area is dimensioned such that the frequency of said device is changed on the order of kilohertz.
Claim 58
Dependent Claim
36 words
A monolithic crystal filter device as described in claim 39, wherein said single contiguous area is dimensioned such that the frequency of at least one of said resonator pairs is changed on the order of kilohertz.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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