JP2005110017A - High frequency filter module and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly miniaturized high frequency filter module which makes full use of a small size that a film bulk acoustic wave resonator has, and to provide a method of manufacturing it at low cost. <P>SOLUTION: This high frequency filter module is provided with: the film bulk acoustic wave resonator which has a mounting board, a substrate and an oscillator formed on the substrate, wherein the oscillator is mounted by a flip chip method above the mounting board so that the oscillator faces without contact with the mounting board; hollow sealing resin for sealing the surroundings of the film bulk acoustic wave resonator so as to hold the oscillator in a hollow space; an electric device connected onto the mounting board; and integral sealing resin for integrally sealing the thin film piezoelectric resonator, the hollow sealing resin and the electric device. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high-frequency band filter module and a manufacturing method thereof, and more particularly, to a high-frequency filter module having a thin film piezoelectric resonator and a manufacturing method thereof.

  In recent years, wireless communication technology has made remarkable progress, and has continued to be developed for the purpose of high-speed transmission of information. Looking at the frequency range used in these wireless communication technologies, the frequency band around 2 GHz has been widely used in the market due to the introduction of PHS (Personal Handyphone System) system, third generation mobile communication, wireless LAN (Local Area Network), etc. The number of subscribers and the number of terminals are also increasing dramatically. For the purpose of speeding up the amount of information transmitted, the frequency of the carrier wave itself has further increased, and commercialization up to the 5 GHz band has been started in the wireless LAN system.

  There is a strong demand for reduction in size and weight with respect to these high-frequency communication devices, and it is very important to make them thin so that they can be used with PC cards, particularly in personal computer (PC) applications. Wireless devices such as PC cards are generally roughly classified into an RF front-end unit that processes radio frequency (RF) and a baseband (BB) unit that performs digital signal processing. Of these, the BB portion is a portion that performs signal modulation / demodulation by digital signal processing, and can basically be constituted by an LSI chip based on a Si (silicon) substrate, so the height of the BB portion is It can be easily reduced to about 1 mm or less.

  On the other hand, the RF unit is a part that performs amplification and frequency conversion using a high-frequency signal as an analog signal, and is difficult to configure only with an LSI chip, and has a complicated configuration including many passive components such as an oscillator and a filter. Of the passive components, dielectric filters and LC filters have conventionally been used as filters, but these components are essential for filtering high-frequency signals using the passband characteristics of cavity resonators and LC circuits. However, it is difficult to reduce the size and to make the height below several mm. For this reason, there has been a limit to reducing the size and thickness of these high-frequency devices.

  In order to solve such a problem, a thin film piezoelectric resonator (FBAR) has been attracting attention. A thin film piezoelectric resonator is an element formed on a cavity (air gap) formed on a substrate by sandwiching a thin film piezoelectric body made of aluminum nitride (AlN), zinc oxide (ZnO), or the like between two electrodes. . That is, since the thin film piezoelectric resonator is mainly composed of a thin film on a semiconductor substrate, it can be easily miniaturized and can easily realize a size of 1 mm or less, which is difficult with an existing filter in terms of height. Also, mounting with transistors, ICs, and LSIs is easy. For this reason, by using a thin film piezoelectric resonator in the RF part of a high-frequency communication device, there is a possibility that various types of devices that are significantly smaller than conventional devices can be realized.

  However, to make a thin film piezoelectric resonator together with an amplifier such as a transistor, IC, LSI or a capacitor, a resistor, an inductor, etc. by taking advantage of its small size, there are the following problems. there were.

  That is, since the thin-film piezoelectric resonator uses a bridge structure floating in the air as a vibrator, it becomes inoperable when touched with a conventionally used epoxy resin or the like during mounting. For this reason, in order to configure a module in combination with other elements, it is necessary to make at least the thin film piezoelectric resonator hollow. On the other hand, a suitable module structure has not existed conventionally.

  The present invention has been made on the basis of recognition of such a problem, and an object of the present invention is to provide an ultra-small high-frequency filter module that can sufficiently take advantage of the small size of a thin-film piezoelectric resonator and a manufacturing method thereof at low cost. It is to provide.

  In order to solve the above-described problems, according to the present invention, a mounting board, a board, and a vibrator formed on the board are provided, and the vibrator faces the mounting board without contacting the board. A thin film piezoelectric resonator that is flip-chip mounted on the mounting substrate in a state of being mounted, a hollow sealing resin that seals the periphery of the thin film piezoelectric resonator so that the vibrator is held in the hollow, and the mounting An electrical element connected on a substrate, the thin film piezoelectric resonator, the hollow sealing resin, and an integral sealing resin for integrally sealing the electrical element, A high frequency filter module is provided.

  Here, the hollow sealing resin may have a viscosity before curing of 100 to 200 Pa · s.

  Alternatively, according to the present invention, the mounting substrate, the substrate, and the vibrator formed on the substrate, the mounting in a state where the vibrator is opposed to the mounting board without contacting the mounting board. A thin film piezoelectric resonator flip-chip mounted on a substrate; a sheet-like hollow sealing resin that seals the periphery of the thin film piezoelectric resonator so that the vibrator is held in a hollow space; An integrated sealing resin that integrally seals the electrical element connected to the thin film piezoelectric resonator, the hollow sealing resin, and the electrical element, and is made of the same material as the hollow sealing resin And a high-frequency filter module characterized by comprising:

  Alternatively, according to the present invention, it includes a mounting substrate, a support substrate flip-chip mounted on the mounting substrate, a substrate, and a vibrator formed on the substrate. A thin film piezoelectric resonator flip-chip mounted on the support substrate in a state of facing the support substrate without contacting the support substrate, and the support substrate and the thin film piezoelectric resonator so that the vibrator is held in a hollow space. A hollow sealing resin for sealing the periphery, an electric element connected on the mounting substrate, the support substrate, the thin film piezoelectric resonator, the hollow sealing resin, and the electric element are integrated. A high-frequency filter module is provided, which is provided with an integral sealing resin for sealing.

  Alternatively, according to the present invention, a semiconductor substrate, a substrate, and a vibrator formed on the substrate are provided, and the vibrator is opposed to the semiconductor substrate without contacting the semiconductor substrate. A thin film piezoelectric resonator flip-chip mounted on a substrate, a hollow sealing resin for sealing the periphery of the thin film piezoelectric resonator so that the vibrator is held in a hollow, the thin film piezoelectric resonator, There is provided a high-frequency filter module comprising an integral sealing resin that integrally seals a hollow sealing resin.

  Here, the thin film piezoelectric resonator may have a plurality of bumps exceeding the number of terminals around the vibrator and be flip-chip mounted through the plurality of bumps.

  According to the present invention, a plurality of thin film piezoelectric resonators each including a substrate and a vibrator formed on the substrate are provided on a support substrate so that the vibrator does not contact the support substrate. Flip chip mount in a state of being opposed to each other, seal the periphery of each of the plurality of thin film piezoelectric resonators with a hollow sealing resin so that the vibrator is held in the hollow, and cut the support substrate Thus, each of the plurality of thin film piezoelectric resonators is separated into pieces together with the support substrate, and the thin film piezoelectric resonator separated into pieces together with the support substrate is fixed on a mounting substrate, and another electric element is obtained. A method of manufacturing a high frequency filter module is provided.

  In the present specification, the “thin film piezoelectric resonator” is different from a ceramic resonator or a SAW (surface acoustic wave) device, and resonance using an elastic wave in the thickness direction of the thin film, that is, the entire film with the thin film as a bulk. This means a resonator using the elastic wave.

  According to the present invention, it is possible to provide a high-frequency filter module having a high-frequency band thin film piezoelectric resonator that is small in size, low in cost, and high in yield, and a method for manufacturing the same.

  The present inventor studied and prototyped an integrated mounting module having an amplifier, a passive component such as a capacitor, and a thin film piezoelectric resonator, such as a high-frequency front end. As a result, in order to mount a thin film piezoelectric resonator that requires hollow sealing integrally with these other components at low cost, it is optimal to use multiple appropriate resins according to the purpose. It has been found that an integrated module can be realized while maintaining a compact and highly reliable filter made of a piezoelectric resonator.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view showing a high-frequency filter module according to a first embodiment of the present invention. That is, this figure shows a specific example in which the present invention is applied to an amplifier transmitter module for 2 GHz W-CDMA (wideband-code division multiple access). That is, the module of the present embodiment includes a multilayer ceramic substrate 100 and a thin film piezoelectric resonator 110, an amplifier 120, and a passive component 130 mounted thereon. The multilayer ceramic substrate 100 has a structure in which a wiring layer 103 and vias 104 and 105 are provided in an insulating substrate. The thin film piezoelectric resonator 110 is connected to the substrate 100 by bumps 150. The amplifier 120 is appropriately wired by a wire 122. The passive component 130 is connected to the substrate 100 by the bumps 132.

  As will be described in detail later, the thin film piezoelectric resonator 110 includes a substrate 111 and a vibrator 112 formed in a bridge shape thereon. In the present embodiment, the thin film piezoelectric resonator 110 is mounted such that the vibrator 112 faces the multilayer ceramic substrate 100. Further, the periphery of the thin film piezoelectric resonator 110 is hollow-sealed with a hollow sealing resin 140 made of NCP (Non Conductive Polymer), and further sealed with other parts by a resin (epoxy resin) 160 from above. Has been. In this way, the integral sealing resin (epoxy) 160 is prevented from wrapping around the vibrator 112 of the thin film piezoelectric resonator 110, and the vibrator 112 of the thin film piezoelectric resonator 110 is stably placed in the hollow portion 142. Can be retained.

  FIG. 2 is a cross-sectional view illustrating a schematic structure of the thin film piezoelectric resonator 110.

The thin film piezoelectric resonator 110 obtains frequency resonance in the thickness direction in which the lower electrode and the upper electrode in contact with the air layer and the piezoelectric film are combined, and has a thickness in the range of 0.5 μm to several μm, which is easy to make by film formation. Corresponds to several GHz, which is advantageous for resonance in the high frequency region of the GHz band. The thin film piezoelectric resonator 110 illustrated in FIG. 2 includes a bridge-type vibrator 112 formed on a Si (silicon) substrate 111. That is, the conductive layer 114 is provided on the silicon substrate 111, and the lower electrode 115, the piezoelectric film 116, and the upper electrode 117 are stacked on the conductive layer 114 via the air gap 113. For example, it is possible to obtain a filter characteristic by vibrating a bridge having a sandwich structure in which the lower electrode 115 is made of Al (aluminum), the piezoelectric film 116 is made of AlN (A aluminum nitride), and the upper electrode 117 is made of Ir (iridium).
A filter circuit can be formed by combining such a thin film piezoelectric resonator 110.
FIG. 3 is a schematic diagram illustrating an example of a band-pass filter circuit using the thin film piezoelectric resonator 100. That is, this filter circuit has a “ladder type” structure in which two thin film piezoelectric resonators 110 are connected in series and one thin film piezoelectric resonator 110 is connected in parallel.

  FIG. 4 is a graph showing impedance characteristics of the series resonator and the parallel resonator of the band pass filter. As shown in the figure, the center frequency of the resonators connected in parallel and in series is slightly changed. Here, the resonance frequency of the resonator connected in series and the anti-resonance frequency of the resonator connected in parallel are different. The band pass filter is configured to be matched.

  In the module shown in FIG. 1, a thin film piezoelectric resonator 110 having AlN as a piezoelectric film 116 is employed, three thin film piezoelectric resonators 110 are connected in series, and two thin film piezoelectric resonators 110 are connected in parallel. The “2.5-stage ladder type” filter circuit was adopted.

  Further, the thin film piezoelectric resonator 110 can obtain good characteristics by controlling the orientation of AlN constituting the piezoelectric film 116. As a result of the inventor's trial production, when an AlN thin film was formed by sputtering, the orientation could be controlled to 2 ° or less with an X-ray rocking curve, and high frequency characteristics were obtained. Further, by performing stress control, the bridge portion, that is, the portion above the air gap 113 can be stabilized. The air gap 113 can be formed by forming a sacrificial layer (not shown) in a pattern on the substrate 111, forming an air bridge structure thereon, and then etching away the sacrificial layer.

  Further, the passband frequency of the filter provided in the module of FIG. 1 is adjusted to 1.92 to 1.98 GHz. This frequency adjustment is performed by appropriately adjusting the thickness of the piezoelectric film (AlN) 116 or the electrode (Al) 115 of each thin film piezoelectric resonator 110 constituting the filter circuit.

  On the other hand, the amplifier 120 is composed of an MMIC (microwave monolithic integrated circuit) centered on a GaAs-based HBT (heterobipolar transistor). For example, an inductor or a capacitor is mounted as the passive component 130.

  The thin film piezoelectric resonator 110, the amplifier 120, and the passive component 130 are all mounted in the same package in a chip-by-chip format as shown in FIG. The passive component 130 is mounted on the substrate 100 by solder reflow, and the amplifier 120 and the thin film piezoelectric resonator 110 are mounted on the substrate 100 via stud bumps.

  As described above, the thin film piezoelectric resonator 110 is provided so that the vibrator 112 faces the ceramic substrate 100 side. That is, in FIG. 1, the substrate 111 is disposed above the piezoelectric body 116 of the thin film piezoelectric resonator 110. The periphery of the thin film piezoelectric resonator is hollow-sealed by a hollow sealing resin 140 made of highly viscous NCP (Non Conductive Polymer), and the condition is strictly set so that the portion of the vibrator 112 is held in the hollow. Is set.

  5 and 6 are graphs showing the experimental results regarding the hollow sealing of the thin film piezoelectric resonator 110. FIG. This experiment was conducted in the 5 GHz band in order to investigate the change of the thin film piezoelectric resonator 110 precisely. That is, the thin film piezoelectric resonator 110 was flip-chip mounted on the ceramic substrate 100 using Au (gold) bumps 150, and changes in filter characteristics before and after sealing were compared using three types of sealing resins. The Au bump 150 had a height of 20 to 30 μm after mounting.

  FIG. 6 shows the results when normal NCP is used as the sealing resin 140. If normal NCP is used, as shown in FIG. 6B, the vibrator 112 is affected by the capillary penetration phenomenon. As a result, as shown in FIG. 6A, the sealed thin film piezoelectric resonator 110 does not perform a characteristic function as a filter. That is, the vibrator 112 is fixed by the resin 140 and vibration is prevented.

  FIG. 5 shows a result when NCP having high viscosity is used as the sealing resin 140. As shown in FIG. 5A, when the viscosity of NCP is high, a phenomenon in which resin penetrates to the vibrator 112 due to a capillary phenomenon is not seen, and a hollow space 142 is secured. As a result, the filter characteristics can be maintained as shown in FIG.

  In addition to NCP, there is a similar resin called “dam agent”. However, in this case, although there is a filter characteristic, there has been a problem that all transmission absorption characteristics are shifted to a low frequency side. This is considered to have occurred because the volatile component contained in the dam agent adhered to the portion of the vibrator 112 of the thin film piezoelectric resonator 110.

  From the above results, the material of the hollow sealing resin 140 that seals the periphery of the thin film piezoelectric resonator 110 is required to have a high viscosity, a small capillary penetration phenomenon, and a small amount of volatile components. In the present embodiment, the periphery of the thin film piezoelectric resonator 110 is hollow-sealed with a sealing resin 140 made of NCP, and then double-sealed together with the HBT element (amplifier) 120 and the passive component 130 with an epoxy resin 160. By doing so, the reliability with respect to temperature and humidity has been dramatically improved. Note that the distance from the outer periphery of the thin film piezoelectric resonator 110 to the vibrator 112 is preferably 50 μm or more, and a high frequency filter module can be formed with a high yield by further separating 100 μm or more. In addition, by using an NCP viscosity index of 100 to 200 Pa · s, it was possible to produce a high-frequency filter module with high yield and high throughput.

  7 and 8 are schematic cross-sectional views showing a high-frequency filter module as a comparative example. In these drawings, the same elements as those described above with reference to FIGS. 1 to 6 are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 7 represents a so-called “hermetic” module. A hollow mounting method in which a component mounted on the substrate 100 is covered with a hermetic 200 such as metal is also conceivable. However, in the case of this structure, the member cost of the hermetic 200 and the substrate 100 bonded to the hermetic 200 is extremely high, and there is a problem that it cannot be provided at low cost for consumer applications.

  On the other hand, as shown in FIG. 8, the thin film piezoelectric resonator 110 mounted on the substrate 100 is sealed together with other components from the back side by a laminate type resin sheet 300, thereby thin film piezoelectric resonance. It is also conceivable to seal the vessel 110 hollow. However, as a result of the trial production by the present inventor, it was found that the module sealed by this method is weak in humidity and has a problem in reliability. This is because it is difficult to sufficiently suppress the ingress of moisture in the laminate-type resin sheet 300 that enables hollow sealing.

  On the other hand, the W-CDMA amplifier transmitter module to which the present invention is applied was able to achieve the performance of sufficiently ensuring the required system specifications including reliability. Since the filter and the amplifier are integrally mounted on the substrate 100 and integrated design is possible, problems such as phase interference and local leak related to the filter do not occur. In addition, according to the present invention, the characteristic maintenance margin is further improved due to the effect that the thin film piezoelectric resonator 110 is packaged in the same manner as other components, and compared with the comparative examples illustrated in FIGS. The equivalent parts can be reduced by about 50%. In addition, there are problems in terms of phase matching and impedance matching, such as when the transmission line between the amplifier 120 and the thin film piezoelectric resonator 110 in the previous stage is long. The problem has been reduced.

FIG. 9 is a schematic cross-sectional view showing a high frequency filter module according to a second embodiment of the present invention.
FIG. 10 (a) is a partially enlarged view thereof.
Also in these drawings, the same elements as those described above with reference to FIGS. 1 to 8 are denoted by the same reference numerals, and detailed description thereof is omitted.
This example also applies the present invention to a 2 GHz band W-CDMA amplifier transmitter module. The feature of this example is that it is once hollow-sealed with a sheet-like resin 170 in order to prevent the integral sealing resin (epoxy resin) 160 from wrapping around. The sheet-like resin 170 is the same epoxy-based thin and plastic resin as the integral sealing resin 160. In this way, the sealing conditions by the resin sheet 170 are set so that the thin film piezoelectric resonator 110 is hollow.

  When a resin sheet having a thickness of 0.05 mm to 0.5 mm was used, good results were obtained. Even if it is in a sheet form, the capillary penetration phenomenon is not completely eliminated. Therefore, it is important to use the optimum conditions for the curing of the resin 170, particularly with respect to temperature and pressure. According to the present embodiment, the W-CDMA amplifier transmitter module can be designed as a module that sufficiently secures the necessary system specifications. A feature compared to the first embodiment is that reliability is improved. The resin sheet 170 is very close in component to the epoxy resin in the case of integral sealing (phenol curable), and the coefficient of thermal expansion is almost the same after curing. Become.

  Further, as shown in FIG. 10B, the filter characteristics after sealing were extremely excellent, and the sealing yield was high. The data shown in FIG. 10 is also measured in the 5 GHz band in order to grasp the change in the filter characteristics of the thin film piezoelectric resonator 110 more sensitively.

FIG. 11: is a schematic cross section showing the high frequency filter module concerning the 3rd Embodiment of this invention. Also in this figure, the same elements as those described above with reference to FIGS. 1 to 10 are denoted by the same reference numerals, and detailed description thereof is omitted.
In this specific example, the present invention is applied to a 2 GHz band W-CDMA amplifier transmitter module. The feature of this specific example is that the thin film piezoelectric resonator 110 is mounted on the support substrate 180 and the periphery thereof is hollow-sealed with a plastic sheet-like resin 170. That is, the sealing conditions of the resin sheet 170 are set so that the thin film piezoelectric resonator 110 is hollow.

  Details of the module characteristics and the filter are the same as those in the first and second embodiments. As a structural feature of the present embodiment, by separately providing a support substrate 180 for the thin film piezoelectric resonator 110, the degree of freedom in designing thermal characteristics and high frequency characteristics is increased, and the thermal characteristics of the module are increased. The characteristic improvement is obtained. At the same time, a very large merit can be obtained in terms of cost, for example, the portion of the substrate 100 having a large area can be made of resin.

  According to the present embodiment, the substrate 100 on which other components are mounted can be made of resin, and the cost can be reduced to 1/3 or less. As for the amplifier 120, heat dissipation is improved by die-bonding the chip on the substrate 100, while for the thin film piezoelectric resonator 110, the amplifier 120 is mounted on the support substrate 180 made of alumina or the like. The inflow of heat from 120 can be made difficult to receive directly. As a result, it was possible to improve the “thermal droop characteristic” which is one of the transmission characteristics.

This embodiment also has a great feature in its manufacturing method.
12 and 13 are schematic views showing the main part of the method for manufacturing the high-frequency filter module of the present embodiment.

That is, as shown in FIG. 12A, the thin film piezoelectric resonator 110 is first flip-chip mounted on the alumina support substrate 180 in a lump. Next, as shown in FIG. 12B, the epoxy resin sheet 170 is thermocompression bonded from the back after mounting, and is sealed hollow.
After that, as shown in FIG. 12C, it is cut into pieces by a dicer. Since the chip of the thin film piezoelectric resonator separated in this way is sealed hollow, it can be handled as a normal part.

  Thereafter, as shown in FIG. 13A, all of the separated thin film piezoelectric resonator 110 filter, amplifier 120, and passive component 130 are formed on the same substrate 100 in a chip-by-chip format. Implement above. The passive component 130 can be mounted by solder reflow, and can be mounted by amplifier 120 and thin film piezoelectric resonator 110 die bonding. Furthermore, wire bonding is performed on the amplifier 120.

  Finally, as shown in FIG. 13B, the whole is integrally sealed with the epoxy resin 160 to complete the main part of the high-frequency filter module.

  According to the method described above, since the hollow sealing of the thin film piezoelectric resonator 110 can be performed collectively, the throughput can be greatly improved. This is advantageous in that it is easier than drawing the NCP resin around the thin film piezoelectric resonator 110 with a dispenser, or placing the resin sheet 170 on the substrate 100 only on the portion of the thin film piezoelectric resonator 110 and crimping it. is there.

  FIG. 14 is a schematic cross-sectional view showing a high frequency filter module according to a fourth embodiment of the present invention. Also in this figure, the same elements as those described above with reference to FIGS. 1 to 13 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In this specific example, the present invention is applied to a reception-side high-frequency front end for a wireless LAN of 5 GHz band. The feature of this example is that the thin film piezoelectric resonator 110 is directly flip-chip mounted on the semiconductor element 190 and sealed hollow. The semiconductor element 190 is formed of an LNA (low noise amplifier), a DC (down converter), and a VCO (voltage controlled oscillator). In the case of this specific example as well, a structure that combines the hollow sealing of the portion of the thin film piezoelectric resonator 110 and the reliability as a module in which the semiconductor element 190 and the filter are integrated by double resin sealing. Can be. The upper surface of the module is a so-called CSP (Chip Scale Package) which also serves as a semiconductor substrate. After a pad region is formed on the semiconductor element 190, the thin film piezoelectric resonator 110 is flip-chip mounted with an Au (gold) pad, and is hollow-sealed with a resin sheet 170 in which a conductive electrode to the semiconductor element 190 is embedded. The whole was further covered with a liquid resin 160 and ground and flattened.

  The passband frequency of the filter is adjusted to 5.03 to 5.25 GHz. The thin film piezoelectric resonator filter operates as a high performance interstage filter, and the module size can be reduced to 2 mm × 2 mm × 0.5 mm.

  FIG. 15 is a schematic diagram showing a planar arrangement of a thin film piezoelectric resonator 110 according to the fifth embodiment of the present invention. That is, this specific example defines an appropriate bump shape of the thin film piezoelectric resonator 110. In the normal thin film piezoelectric resonator 110, a total of six bumps are provided for the input side ground G, signal line IS, and ground G, and output side ground G, signal line OS, and ground G. In contrast, in the present embodiment, as shown in FIG. 15, a total of 12 bumps are provided. Moreover, the positions of the bumps are devised alternately. This is advantageous in that the bump itself is used to prevent the encapsulating resin from being wrapped around. The yield can be further increased by applying the thin film piezoelectric resonator 110 of the present embodiment to the first to fourth embodiments.

  The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.

  For example, each of the above-described embodiments can be used singly, but some of them can be combined to achieve a greater effect. The thin film piezoelectric resonator 110 may be used not only as a filter but also as a voltage controlled oscillator. Alternatively, an element combining MEMS (Micro-Electro-Mechanical Systems) may be used.

  In addition, all high-frequency filter modules or manufacturing methods that can be implemented by those skilled in the art based on the above-described high-frequency filter module or manufacturing method thereof as embodiments of the present invention are also included in the scope of the present invention. Belonging to.

It is a schematic cross section showing the high frequency filter module concerning a 1st embodiment of the present invention. 2 is a cross-sectional view illustrating a schematic structure of a thin film piezoelectric resonator 110. FIG. 4 is a schematic diagram illustrating an example of a band-pass filter circuit using the thin film piezoelectric resonator 100. FIG. It is a graph showing the impedance characteristic of the series resonator and parallel resonator of a band pass filter. It is a graph showing the experimental result regarding the hollow sealing of the thin film piezoelectric resonator. It is a graph showing the experimental result regarding the hollow sealing of the thin film piezoelectric resonator. It represents a so-called “hermetic” module. FIG. 4 is a schematic diagram showing a structure in which a thin film piezoelectric resonator 110 mounted on a substrate 100 is sealed together with other components from a back surface by a laminate type resin sheet 300. It is a schematic cross section showing the high frequency filter module concerning a 2nd embodiment of the present invention. It is a graph showing the result of having investigated the filter characteristic after sealing. It is a schematic cross section showing the high frequency filter module concerning a 3rd embodiment of the present invention. It is a schematic diagram showing the principal part of the manufacturing method of the high frequency filter module of this embodiment. It is a schematic diagram showing the principal part of the manufacturing method of the high frequency filter module of this embodiment. It is a schematic cross section showing the high frequency filter module concerning the 4th Embodiment of this invention. It is a schematic diagram showing planar arrangement | positioning of the thin film piezoelectric resonator 110 concerning the 5th Embodiment of this invention.

Explanation of symbols

100 substrate (mounting substrate)
DESCRIPTION OF SYMBOLS 110 Thin film piezoelectric resonator 111 Silicon substrate 112 Vibrator 113 Air gap 114 Conductive layer 115 Lower electrode 116 Piezoelectric body 117 Upper electrode 120 Amplifier 130 Passive component 140 Hollow sealing resin 142 Hollow part 150 Bump 160 Epoxy resin (integrated sealing resin)
170 Resin sheet 180 Support substrate 190 Semiconductor element 200 Hermetic 300 Resin sheet

Claims (7)

A mounting board;
A thin film piezoelectric resonator having a substrate and a vibrator formed on the substrate, wherein the vibrator is flip-chip mounted on the mounting substrate in a state of being opposed to the mounting substrate without contacting the mounting substrate. ,
A hollow sealing resin for sealing the periphery of the thin film piezoelectric resonator so that the vibrator is held in the hollow;
An electrical element connected on the mounting substrate;
An integral sealing resin for integrally sealing the thin film piezoelectric resonator, the hollow sealing resin, and the electrical element;
A high frequency filter module comprising:   The high-frequency filter module according to claim 1, wherein the hollow sealing resin has a viscosity of 100 to 200 Pa · s before curing. A mounting board;
A thin film piezoelectric resonator having a substrate and a vibrator formed on the substrate, wherein the vibrator is flip-chip mounted on the mounting substrate in a state of being opposed to the mounting substrate without contacting the mounting substrate. ,
A sheet-like hollow sealing resin that seals the periphery of the thin film piezoelectric resonator so that the vibrator is held in the hollow;
An electrical element connected on the mounting substrate;
The thin film piezoelectric resonator, the hollow sealing resin, and the electric element are integrally sealed, and an integral sealing resin made of the same material as the hollow sealing resin;
A high frequency filter module comprising: A mounting board;
A support substrate flip-chip mounted on the mounting substrate;
A thin film piezoelectric resonator having a substrate and a vibrator formed on the substrate, wherein the vibrator is flip-chip mounted on the support substrate in a state of being opposed to the support substrate without contacting the support substrate; ,
A hollow sealing resin for sealing the periphery of the support substrate and the thin film piezoelectric resonator so that the vibrator is held in the hollow;
An electrical element connected on the mounting substrate;
An integrated sealing resin that integrally seals the support substrate, the thin film piezoelectric resonator, the hollow sealing resin, and the electrical element;
A high frequency filter module comprising: A semiconductor substrate;
A thin film piezoelectric resonator having a substrate and a vibrator formed on the substrate, wherein the vibrator is flip-chip mounted on the semiconductor substrate in a state of facing the semiconductor substrate without contacting the semiconductor substrate; ,
A hollow sealing resin for sealing the periphery of the thin film piezoelectric resonator so that the vibrator is held in the hollow;
An integral sealing resin for integrally sealing the thin film piezoelectric resonator and the hollow sealing resin;
A high frequency filter module comprising:   6. The thin film piezoelectric resonator has a plurality of bumps exceeding the number of terminals around the vibrator, and is flip-chip mounted through the plurality of bumps. The high frequency filter module as described in any one. A flip chip in which a plurality of thin film piezoelectric resonators having a substrate and a vibrator formed on the substrate are opposed to the support substrate without contacting the support substrate. Mount and
The periphery of each of the plurality of thin film piezoelectric resonators is sealed with a hollow sealing resin so that the vibrator is held in the hollow,
By cutting the support substrate, each of the plurality of thin film piezoelectric resonators is separated into pieces together with the support substrate,
A method of manufacturing a high-frequency filter module, wherein the thin film piezoelectric resonator separated into pieces together with the support substrate is fixed on a mounting substrate and resin-sealed integrally with other electric elements.

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