DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 02/07/2025 is/are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement are being considered by the examiner.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1, 3, and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang (US8345513B2) in view of Horsley (US10562069B2).
Claim 1
Huang teaches: A semiconductor device, comprising:
a first microelectromechanical system (MEMS) structure (711) over a first substrate (615), wherein the first MEMS structure (711) comprises a first flexible membrane (612) and a first cavity between the first substrate (615) and the first flexible membrane (612); and
a second MEMS structure (712) on a second substrate (616) that is connected to a conductive layer (611) over the first substrate (615), and the second MEMS structure (712) stacked above the first MEMS structure (711), wherein the second MEMS structure (712) comprises a second flexible membrane (722) overlying a second cavity (723) of the second substrate (616), and the second cavity (723) is positioned above the first cavity; wherein the first MEMS structure (711) and the second MEMS structure (712) are independently coupled (first CMUT structure 711 and second CMUT structure 712 may operate independently of each other, especially when the two CMUTS 711 , 712 operate in separate frequency ranges; see para. 0047) to an interconnect structure over the first substrate (615).
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Huang does not expressly disclose: [the] second substrate [being] bonded to a conductive layer over the first substrate.
Horsley notably teaches a PMUT device comprising first and second substrates 10 and 104 bonded together using a conductive bonding layer 106. The conductive bonding layer 106 provides both a mechanical connection between the substrates and an electrical connection between conductive layer/electrode 124 on the first substrate and electrical interconnect 114 on the second substrate (see para. 0017).
It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to employ a similar conductive substrate bonding arrangement of Horsley to the stacked CMUT arrangement of Huang to provide both mechanical attachment and electrical connection of the stacked ultrasonic transducer structures to an underlying electrical interconnect. Both references concern MEMs ultrasonic transducers, and the use of a conductive bonding layer to mechanically and electrically couple transducer substrates.as a known technique. The resulting combination would provide the predictable benefit of electrically coupling the stacked transducers while mechanically joining the substrate structures.
Claim 3/1
Huang as modified by Horsely teaches: The semiconductor device of Claim 1, but does not expressly disclose: wherein the first MEMS structure (711) further comprises a first bottom electrode (617) and a first top electrode (611), wherein the first cavity (618) is formed between the first top electrode (611) and the first bottom electrode (617), and the first top electrode (611) comprise or be a part of (via connector supports 614) the first flexible membrane (612).
Claim 9/1
Huang as modified by Horsely teaches: The semiconductor device of Claim 1, wherein the first MEMS structure (711) includes a plurality of first MEMS ultrasonic transducers (1-D array, 1.5-D array, 1.75-D array, 2-D array, annular array) arranged as an array over the first substrate (615), and the second MEMS structure (712) is positioned above the array of the first MEMS ultrasonic transducers correspondingly, wherein each of the first MEMS ultrasonic transducers includes the first flexible membrane (612) and the first cavity between the first substrate (615) and the first flexible membrane (612).
Claim 10
Huang teaches: A method of forming a semiconductor device, comprising: providing a first semiconductor structure that comprises a first microelectromechanical system (MEMS) structure (711) over a first substrate (615), wherein the first MEMS structure (711) comprises a first flexible membrane (612) and a first cavity between the first substrate (615) and the first flexible membrane (612), and the first flexible membrane (612) is configured to vibrate at a first frequency (first CMUT is independently operated at separate frequency ranges to the second CMUT; see para. 0031 and 0047); providing a second semiconductor structure that comprises a second MEMS structure (712) on a second substrate (616), wherein the second MEMS structure (712) comprises a second flexible membrane (722) overlying a second cavity (723) of the second substrate (616), and the second flexible membrane (722) is configured to vibrate at a second frequency (second CMUT is independently operated at separate frequency ranges to the first CMUT; see para. 0031 and 0047); wherein the second MEMS structure (712) is vertically stacked above the first MEMS structure (711); and electrically connecting the second MEMS structure (712) to an interconnect structure (611) over the first substrate (711).
Huang is silent, however, to: bonding the second semiconductor structure to the first semiconductor structure;
Horsley notably teaches a PMUT device comprising first and second substrates 10 and 104 bonded together using a conductive bonding layer 106. The conductive bonding layer 106 provides both a mechanical connection between the substrates and an electrical connection between conductive layer/electrode 124 on the first substrate and electrical interconnect 114 on the second substrate (see para. 0017).
It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to employ a similar conductive substrate bonding arrangement of Horsley to the stacked CMUT arrangement of the prior art to provide both mechanical attachment and electrical connection of the stacked ultrasonic transducer structures to an underlying electrical interconnect. Both references concern MEMs ultrasonic transducers, and the use of a conductive bonding layer to mechanically and electrically couple transducer substrates.as a known technique. The resulting combination would provide the predictable benefit of electrically coupling the stacked transducers while mechanically joining the substrate structures.
Claim 11/10
Huang as modified by Horsely teaches: The method of Claim 10, but does not expressly disclose in the embodiment used in Claim 10: wherein the first frequency is an ultrasound frequency.
Huang does however disclose in an additional embodiment of their semiconductor device that stacked CMUT structures are ultrasonic transducers configured for transmitting and receiving ultrasound. In particular, first CMUT 1011 may operate at a lower center frequency of approximately 0.5-3MHz for HIFU, while second CMUT 1012 may operate at a higher center frequency of approximately 5-10MHz for ultrasound frequency (see para. 0056-0057).
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Thus, the first frequency is an ultrasound frequency, and it would therefore have been obvious to a person having ordinary skill in the art before the claimed invention was filed to employ a first frequency of the first CMUT within the disclosed ultrasound frequency range for HIFU or other ultrasonic operation. Such a modification would enable the first CMUT to perform HIFU treatment using a lower frequency ultrasound signal.
Claim 12/10
Huang as modified by Horsely teaches: The method of Claim 10, wherein the second cavity (723) is positioned above the first cavity and shields the first cavity (618).
Claim(s) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley in view of Margalit (US20240340576A1) and Margalit2 (US2016360320A1).
Claim 2/1
Huang as modified by Horsely teaches: The semiconductor device of Claim 1, but does not expressly disclose: wherein the first MEMS structure is configured to be an ultrasound pump, and the second MEMS structure is configured to be a frequency modulator.
Margalit conversely teaches an ultrasonic pump having vertically arranged first, second, and third membranes 101, 107, and 111, wherein the first and third membranes are actuated to generate fluid flow. Fig. 1B for example shows an enclosed fluid volume 127 defined between the first and third membranes, with fluid conduits 123 and 125 communicating with the enclosed volume. Figs. 3A-3D for example, illustrate movement of the membranes in response to periodic actuation signals, including different phase relationships between the first and third membranes. Fig. 4A illustrates the movement of the membranes changes the volume and pressure of enclosed volume 127, thereby causing fluid to be drawn into or expelled from the volume and producing pump action (see para. 0046-0051).
Margalit further teaches that the membranes have respective mechanical resonance frequencies and that actuation at a resonance frequency produces maximum membrane displacement (ex. Fig. 10A; para. 0058). Margalit further discloses ultrasonic resonance frequencies including 100-200kHz, 200-400kHz, 400-600kHz, and above 600kHz. Thus, Margalit teaches configuring a MEMs membrane structure as an ultrasonic pump and actuating the membrane at a first ultrasonic frequency.
It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to configure the MEMs structure of the prior art as an ultrasonic pump as taught by Margalit because Margalit expressly teaches vertically arranged MEMs type structures and an enclosed fluid volume that cooperate to generate fluid flow, thereby providing a known ultrasonic pumping implementation for a MEMs membrane structure.
Margalit2 teaches a MEMs based acoustic system comprising an oscillation membrane 302 and a MEMs shutter 303. The oscillation membrane is configured to generate an ultrasonic acoustic carrier signal 321 at a carrier frequency fc, while the MEMs shutter is configured to modulate the ultrasonic carrier signal in response to a modulation signal 333 having a modulation frequency fm (see figs. 2 and 3; see para. 0038-0048, and 0050-0053). Margalit further explains that the modulation frequency fm is the frequency of modulation of the MEMs shutter and that the resulting modulated signal includes a lower frequency component based on the frequency difference between the carrier frequency fc and modulation frequency fm.
Thus, the MEMs shutter 303 provides the claimed frequency modulating second MEMs structure, while the oscillation membrane 302 provides the higher frequency ultrasonic first MEMs structure. It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to employ a similar frequency modulating MEMs structure to Margalit2 with the ultrasonic MEMs pump arrangement of Huang and Margalit to provide controlled modulation of the ultrasonic output and thereby generate a desired lower frequency acoustic component.
Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley in view of Tsai (US2021078857A1).
Claim 4/1
Huang as modified by Horsely teaches: The semiconductor device of Claim 1, wherein the second MEMS structure (712) further comprises: a shared bottom electrode 611 and a top electrode (721) on the flexible membrane (722).
Huang does not expressly disclose: a second bottom electrode on the second flexible membrane; a second top electrode over the second bottom electrode; and an actuator layer between the second top electrode and the second bottom electrode.
Tsai conversely teaches a PMUT device having a membrane stack including a top electrode 104PT, a piezoelectric layer 104PM, and a bottom electrode 104PB. The piezoelectric layer 104PM is disposed of between the top and bottom electrodes and operates through the piezoelectric effect to generate ultrasonic waves in response to an applied electric field. Accordingly, the bottom electrode 104PB, top electrode 104PT, and piezoelectric layer 104PM correspond to the claimed second bottom electrode, second top electrode, and actuator layer, respectively.
It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to employ a similar piezoelectric membrane stack configuration of Tsai in the second CMUT structure of the prior art to provide a piezoelectrically actuated ultrasonic transducer and thereby obtain the known ultrasonic generation functionality of a PMUT. Tsai expressly teaches integration of PMUT and CMUT devices in a hybrid ultrasonic transduce, making the modification applicable to the stacked ultrasonic transducer architecture disclosed by Huang.
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley in view of Huang2 (US8363514B2).
Claim 5/1
Huang as modified by Horsely teaches: The semiconductor device of Claim 1 but does not expressly disclose: further comprising: a controller independently coupled to the first MEMS structure and the second MEMS structure wherein the controller independently applies actuation voltages to first MEMS structure and the second MEMS structure (712) during operation of the semiconductor device.
Huang2 conversely teaches two CMUTs 101 and 101A that are individually addressed and provided with respective input signals from input signal sources 110 and 110A. Huang2 explains that different input signal may be applied to the respective CMUTS and that the CMUTs may therefore have different operation voltages and operate under different conditions. Each CMUT is also switched between transmission and reception modes using respective switches 108 and 108A.
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Accordingly, Huang2 supplies the independent voltage control aspect not expressly provided by Huang. It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to provide the independently operated stacked CMUTs 711 and 712 of the prior art with the individually addressed voltage control arrangement of Haung2, including separate input signals and operation voltages, to permit the respective CMUTs to be independently controlled and operated under different operating conditions. Such a modification would have been a predictable use of a known individual addressing and voltage control technique in the stacked CMUT architecture.
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley in view of Lin (US9938134B2).
Claim 6/1
Huang as modified by Horsely teaches: The semiconductor device of Claim 1, but does not expressly disclose: wherein a bonding structure vertically extends between the second substrate and the conductive layer over an interconnect structure on the first substrate, and the bonding structure is positioned within a periphery region of the second substrate.
Lin conversely teaches a MEMs structure bonded to an underlying logic substrate having an interconnect structure. Specifically, Lin discloses a MEMs substrate 108 having a downwardly extending protrusion 230 positioned in a peripheral opening 216 of a passivation layer 214. The underlying logic chip 104 includes an interconnect structure 206 having interconnect layers 208. A eutectic bond layer 232 is positioned between the protrusion 230 and the upper interconnect layer 208 and bonds and electrically couples the MEMs substrate 108 to the logic chip 104. The protrusion 230 extends laterally to enclose the cavity 110, thereby providing the claimed peripheral bonding structure.
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Lin expressly describes the eutectic bond layer 232 as being between the top interconnect layer 108 and the bottom surface of protrusion 230, and describes the protrusion as extending laterally to enclose the cavity. Lin also describes forming the eutectic bond layer and hard mask in a ring shape (see para 0034). It would have been obvious to a person having ordinary skill in the art before ethe claimed invention was filed to modify the prior art’s stacked CMUT structure to employ a similar peripheral substrate to interconnect bonding arrangement of Lin. Lin demonstrates a known concept of bonding a MEMs substrate to an underlying substrate/interconnect structure using a vertically extending conductive bonding structure located around the MEMs cavity. Applying such a peripheral bonding arrangement to Huang’s stacked MEMs structure would provide mechanical attachment and electrical coupling while preserving the compact vertically stacked MEMs configuration.
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley and Lin in view of Teng (US9269679B2).
Claim 7/6/1
Huang as modified by Horsely and Lin teaches: The semiconductor device of Claim 6, but does not expressly disclose: wherein the first MEMS structure includes first MEMS devices arranged as an array, when the second substrate is bonded to the conductive layer over the interconnect structure on the first substrate by the bonding structure, the bonding structure surrounds the first MEMS devices in top view.
Teng conversely teaches a wafer level packaging technique for MEMs related structures. Teng provides support for the array/surrounding bond ring concept. Teng expressly teaches a wafer level package having a second substrate comprising a plurality of MEMs devices, with an array of bond ring structures arranged between first and second substrates. Teng also expressly describes a MEMs bond ring 408 surrounding the periphery of a MEMs device and being bonded to a CMOS bond ring 404.
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Teng ultimately teaches that he package can have a first substrate, a second substrate comprising a plurality of MEMs devices, and an array of bond ring structures between the substrates and further describes the MEMs bond ring as surrounding the periphery of the MEMs device.
It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to apply a similar peripheral/ring shaped bonding arrangement of Lin to the array configuration of Huang, as further taught by Teng, such that the bonding structure surrounds the array of the first MEMs devices. Teng demonstrates that surrounding MEMs devices with peripheral bond rings is a known wafer level packaging technique, including where a plurality of MEMs devices are provided on a substrate.
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley and Lin in view of Hideo (US7728487B2).
Claim 8/1
Huang as modified by Horsely teaches: The semiconductor device of Claim 1, wherein the first MEMS structure (711) is a capacitive micromachined ultrasonic transducer (CMUT), and the second MEMS structure (712) is a capacitive micromachined ultrasonic transducer (CMUT). Huang also acknowledges the use of piezoelectric transducers however, Huang has preferably opted for a MUT structure as an alternative as MUTs can be manufactured using more efficient semiconductor micromachining techniques, and MUTs demonstrate a comparable dynamic performance to PZT transducers (see para. 0003).
Huang however does not disclose that: the second MEMS structure is a piezoelectric micromachined ultrasonic transducer (PMUT).
Hideo teaches an ultrasound transducer having a CMUT 32 and PMUT 33. The PMUT includes a piezoelectric film 46 and electrodes 35 and 36, while the CMUT employs electrostatic transduction. Hideo expressly teaches combining the CMUT and PMUT to increase transmitted ultrasound output and receiving sensitivity.
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It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to modify the stacked CMUT arrangement of the prior art by implementing the second stacked transducing structure as the PMUT of Hideo, while retaining the first CMUT, in order to obtain the known benefits of combining electrostatic and piezoelectric ultrasound transduction, including increased ultrasound transmission output and receiving sensitivity.
Claim(s) 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley in view of Cohn (US7750462B1).
Claim 13/10
Huang as modified by Horsely teaches: The method of Claim 10, wherein the second substrate (616) is bonded to a conductive layer (611) over the first substrate (615);
Huang as modified by Horsely does not expressly disclose: the second substrate is bonded to a conductive layer over the first substrate by thermal compression bonding.
Cohn conversely teaches thermocompression bonding of a MEMs substrate to another substrate. IN particular, first and second substrates 120 and 140 are placed in aligned confronting relation and subject to heat and pressure, causing conductive bonding features 160 and 160’ to plastically deform and form thermocompressive bonds. Cohn further teaches that, when conductive bonding material is used, the resulting thermocompression bonds can both mechanically bond the substates and electrically couple devices disposed on the respective substrates (see para. 0041-0046).
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It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to employ the thermocompression bonding technique of Cohn to bond the second substrate of the prior art to a conductive layer over the first substrate, thereby providing both mechanical bonding and electrical interconnection between the stacked MEMs structure and the underlying interconnect structure. This technique may also permit small conductive contacts and reduced parasitic capacitance.
Claim(s) 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley and Lin in view of Shim (US9643212B2).
Claim 14/10
Huang as modified by Horsely teaches: The method of Claim 10, but does not expressly disclose: wherein the second MEMS structure is electrically connected to the interconnect structure by wire bonding.
Shim conversely teaches electrically connecting a CMUT chip 110 to an electrical circuit 150 using wire bonding. In particular, the CMUT chip includes first electrode pads 120, and the electrical circuit includes corresponding second electrode pads 160, and wires 170 electrically connecting the first electrode pads 1230 to the second electrode pads 160 by wire bonding.
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It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to connect the second MEMs structure of the stacked transducer taught by the prior art to the interconnect structure using the wire bonding technique of Shim thereby providing a known electrical connection between a MEMs/CMUT structure and associated circuitry.
Claim(s) 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley in view of Chiu (US8716070B2).
Claim 15/10
Huang as modified by Horsely teaches: The method of Claim 10, but does not expressly disclose: further comprising: electrically connecting a conductive contact of the interconnect structure to an external electrical component; and mounting a lid on the external electrical component to cover th1e second semiconductor structure and the first semiconductor structure stacked vertically, thereby providing an assembly structure package.
Chiu conversely teaches packaging a MEMs element 141 disposed on a chip 14, wherein the chip includes electrical connection pads 140, and a lid 12 is mounted on the chip to cover the EMs element. Chiu further teaches conductive contacts 122 electrically connected to the electrical connection pads 140, wherein the contacts 122 are used to electrically connect the chip to another electronic element.
It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to electrically connect a conductive contact of the interconnect structure of the device of the prior art to an external electrical component as taught by Chiu and to mount the disclosed lid over the stacked MEMs structures to provide a packaged assembly. Such a configuration would protect the MEMs structures while providing an external electrical interface for connection to other electronic circuitry.
Claim(s) 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang in view of Horsley and Lin2 (US2018086627A1).
Claim 16
Huang teaches: A method of forming a semiconductor device, comprising: providing an integrated circuit (IC) structure (integrated circuits may be formed on 611; see para. 0045) over a first substrate (615); wherein the first MEMS structure (711) comprises a first flexible membrane (612) and a first cavity between the first substrate (615) and the first flexible membrane (612), and the first MEMS structure (711) is coupled to an IC device (611) on the first substrate (615); providing a second substrate (616) with a second MEMS structure (712), wherein the second MEMS structure (712) comprises a second flexible membrane (722) overlying a second cavity (723) of the second substrate (616); and the second MEMS structure (712) stacked above the first MEMS structure (711), wherein the second cavity (723) is positioned between the second flexible membrane (722) and the first flexible membrane (612).
Huang doesn’t expressly disclose: providing an integrated circuit (IC) structure that comprises an interconnect structure over a first substrate; forming a first microelectromechanical system (MEMS) structure over the IC structure; the first MEMS structure is coupled to an IC device on the first substrate; and bonding the second substrate to a conductive layer over the interconnect structure.
Lin2 teaches integrating a MEMs structure with an interconnect structure formed over a semiconductor substrate. For example, Lin discloses an integrated MEMs structure over a substrate and conductive interconnects formed through an insulating layer, including interconnect 505 formed through ILD layer 508 and further interconnect layers including conductive interconnects 417 and 419.
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It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to implement the first MEMs structure of Huang over an integrated circuit/interconnect structure as taught by Lin2, thereby providing the first MEMs structure over an IC structure having an interconnect structure over the first substrate. Such a modification would provide the benefit of electrically coupling the MEMs structure with semiconductor circuitry through the underlying interconnect structure.
Horsley notably teaches a PMUT device comprising first and second substrates 10 and 104 bonded together using a conductive bonding layer 106. The conductive bonding layer 106 provides both a mechanical connection between the substrates and an electrical connection between conductive layer/electrode 124 on the first substrate and electrical interconnect 114 on the second substrate (see para. 0017).
It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to employ a similar conductive substrate bonding arrangement of Horsley to the stacked CMUT arrangement of the prior art to provide both mechanical attachment and electrical connection of the stacked ultrasonic transducer structures to an underlying electrical interconnect. Both references concern MEMs ultrasonic transducers, and the use of a conductive bonding layer to mechanically and electrically couple transducer substrates.as a known technique. The resulting combination would provide the predictable benefit of electrically coupling the stacked transducers while mechanically joining the substrate structures.
Claim(s) 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley and Lin2 in view of Shim.
Claim 17/16
Huang as modified by Horsley and Lin2 teaches: The method of Claim 16, but does not expressly disclose: further comprising: electrically connecting the second MEMS structure (712) to the interconnect structure over the first substrate (615).
Shim conversely teaches electrically connecting a CMUT chip 110 to an electrical circuit 150 using wire bonding. In particular, the CMUT chip includes first electrode pads 120, and the electrical circuit includes corresponding second electrode pads 160, and wires 170 electrically connecting the first electrode pads 1230 to the second electrode pads 160 by wire bonding.
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It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to connect the second MEMs structure of the stacked transducer taught by the prior art to the interconnect structure using the wire bonding technique of Shim thereby providing a known electrical connection between a MEMs/CMUT structure and associated circuitry.
Claim(s) 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley and Lin2 in view of Margalit.
Claim 18/16
Huang as modified by Horsley and Lin2 teaches: The method of Claim 16, wherein the first MEMS structure operated at a first frequency; and the second cavity (723) of the second substrate (616) acts as an ultrasound pumping chamber.
Huang as modified by Lin and Horsley does not expressly teach: wherein the first MEMS structure is configured to be an ultrasound pump to vibrate at a first frequency, and the second cavity of the second substrate acts as an ultrasound pumping chamber.
Margalit conversely teaches an ultrasonic pump having vertically arranged first, second, and third membranes 101, 107, and 111, wherein the first and third membranes are actuated to generate fluid flow. Fig. 1B for example shows an enclosed fluid volume 127 defined between the first and third membranes, with fluid conduits 123 and 125 communicating with the enclosed volume. Figs. 3A-3D for example, illustrate movement of the membranes in response to periodic actuation signals, including different phase relationships between the first and third membranes. Fig. 4A illustrates the movement of the membranes changes the volume and pressure of enclosed volume 127, thereby causing fluid to be drawn into or expelled from the volume and producing pump action (see para. 0046-0051).
Margalit further teaches that the membranes have respective mechanical resonance frequencies and that actuation at a resonance frequency produces maximum membrane displacement (ex. Fig. 10A; para. 0058). Margalit further discloses ultrasonic resonance frequencies including 100-200kHz, 200-400kHz, 400-600kHz, and above 600kHz. Thus, Margalit teaches configuring a MEMs membrane structure as an ultrasonic pump and actuating the membrane at a first ultrasonic frequency.
It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to configure the MEMs structure of the prior art as an ultrasonic pump as taught by Margalit because Margalit expressly teaches vertically arranged MEMs type structures and an enclosed fluid volume that cooperate to generate fluid flow, thereby providing a known ultrasonic pumping implementation for a MEMs membrane structure.
Claim(s) 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley, Lin2, and Margalit in view of Margalit2.
Claim 19/18/16
Huang as modified by Horsley, Lin2 and Margalit teaches: The method of Claim 18, but does not expressly disclose: wherein the second MEMS structure is configured to be a frequency modulator to vibrate at a second frequency, and the second frequency is less than the first frequency.
Margalit2 teaches a MEMs based acoustic system comprising an oscillation membrane 302 and a MEMs shutter 303. The oscillation membrane is configured to generate an ultrasonic acoustic carrier signal 321 at a carrier frequency fc, while the MEMs shutter is configured to modulate the ultrasonic carrier signal in response to a modulation signal 333 having a modulation frequency fm (see figs. 2 and 3; see para. 0038-0048, and 0050-0053). Margalit further explains that the modulation frequency fm is the frequency of modulation of the MEMs shutter and that the resulting modulated signal includes a lower frequency component based on the frequency difference between the carrier frequency fc and modulation frequency fm.
Thus, the MEMs shutter 303 provides the claimed frequency modulating second MEMs structure, while the oscillation membrane 302 provides the higher frequency ultrasonic first MEMs structure. It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to employ a similar frequency modulating MEMs structure to Margalit2 with the ultrasonic MEMs pump arrangement of Huang and Margalit to provide controlled modulation of the ultrasonic output and thereby generate a desired lower frequency acoustic component.
Claim(s) 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Huang as modified by Horsley and Lin2 in view of Lemmerhirt (US8399278B2).
Claim 20/16
Huang as modified by Horsley and Lin2 teaches: The method of Claim 16, but does not expressly disclose: wherein the IC structure is a complementary metal-oxide- semiconductor (CMOS) structure, and the IC device that is coupled to the first MEMS structure is a part of a CMOS circuit.
Lemmerhirt conversely teaches ultrasound system 10 comprising an integrated circuit transducer device comprising a substrate, a complementary metal oxide semiconductor (CMOS) circuit fabricated on the substrate, and a capacitive micromachined ultrasonic transducer (CMUT) element 112 fabricated in the substrate and electrically connected to the CMOS circuit 110. The CMUT includes a lower electrode 116, upper electrode 118, membrane structure 124, and cavity 120.
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It would have been obvious to a person having ordinary skill in the art before the claimed invention was filed to implement the integrated circuit associated with Huang’s first CMUT 711 as a CMOS circuit as taught by Lemmerhirt, thereby providing the claimed CMOS IC structure and CMOS circuit coupled to the first MEMs structure. Such a combination would provide the known benefit of integrating the CMUT and its control/readout circuitry on a common semiconductor substrate, reducing interconnect distance and facilitating compact integration.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to AHMED F SECK whose telephone number is (571)272-4638. The examiner can normally be reached Monday - Friday 7:30 am - 4:30 pm.
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/AHMED F SECK/Examiner, Art Unit 2834
/CHRISTOPHER M KOEHLER/Supervisory Patent Examiner, Art Unit 2834
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