JP4835238B2 - RESONATOR, RESONATOR MANUFACTURING METHOD, AND COMMUNICATION DEVICE - Google Patents

Description

  The present invention relates to a resonator, a method for manufacturing the resonator, and a communication device equipped with a filter having the resonator.

  In recent years, with the progress of miniaturization of mobile products such as mobile phones, there is an increasing demand for smaller, higher density and lower priced products to be installed. As a result, semiconductor IC packages have been dramatically reduced in size and density. Recently, there are many module packages that incorporate multiple IC chips, passive components, and other functional devices, rather than single IC packages. Proposed. Among the components used in this module package, technologies such as thin film bulk acoustic resonators (hereinafter referred to as FBARs) have been shown by various companies, for example, as a representative of SAW as a filter device. (See Patent Document 1).

  However, the conventional FBAR structure has a limit in the heat dissipation of the resonator, which is disadvantageous in terms of device characteristics such as power durability.

  A conventional FBAR structure example will be described with reference to FIG. The membrane type resonator (FBAR) 101 shown in FIG. 15 has a space 112 immediately below a resonator 116 formed of a buffer layer 121, a lower electrode 113, a piezoelectric film 114, and an upper electrode 115 on a substrate 111. Although dielectric loss and power loss are small and excellent in characteristics, the heat dissipation of the resonator 116 is inferior. That is, the membrane-type resonator 101 is inferior in power durability.

  As shown in FIG. 16, for example, when a power durability test is performed, heat generated in the resonator 116 is accumulated, and the center of the resonator 116 is destroyed. In the resonator 101 having the space 112 immediately below the resonator 116, heat generated by the resonator 116 which is a thin film is transmitted only in the horizontal direction (direction indicated by the arrow in the figure), and the outer peripheral portion of the resonator 116 is transferred. This is probably because there is only a heat dissipation path for heat dissipation to the silicon (Si) substrate 111. For this reason, the heat that has lost the escape is accumulated in the central portion of the resonator 116 and easily burns out at that portion.

JP 2004-357306 A

  The problem to be solved is that since the heat dissipation path of the resonator is not sufficiently secured, the heat that has lost the escape field is accumulated in the center of the resonator and is easily burned out.

  It is an object of the present invention to secure a heat dissipation path for a resonator and improve the heat dissipation characteristics of the resonator.

According to a first aspect of the present invention, there is provided a first electrode disposed on a substrate with a space around the substrate, a piezoelectric film formed on the first electrode, and the piezoelectric film. A resonator including a resonator having a second electrode formed thereon, wherein a heat radiating portion in contact with the substrate and the first electrode is provided at a central portion of the space. And

  According to the first aspect of the present invention, since the heat radiating portion for radiating the heat generated in the resonator to the substrate side is formed, the heat radiation characteristic of the resonator is improved and the resonator is prevented from being burned out.

  According to a sixth aspect of the present invention, there is provided a step of forming a sacrificial film for forming a space on the substrate, and a step of forming a first electrode that covers the sacrificial film and is supported on the substrate. Forming a piezoelectric film on the first electrode; forming a second electrode on the piezoelectric film; and removing the sacrificial film to create a space between the substrate and the first electrode. Forming a sacrificial film, wherein a hole reaching the substrate surface is formed in a central portion where the space is formed, and the hole is formed through the hole. The first electrode is formed in contact with the substrate surface.

  In the present invention according to claim 6, when the sacrificial film is formed, a hole reaching the substrate surface is formed in the central part where the space is formed, and the first electrode is formed in contact with the substrate surface through the hole. Thus, since the heat radiating portion for radiating the heat generated in the resonator to the substrate side is formed, a resonator having high heat dissipation characteristics and a resonator in which the resonator is prevented from being burned is manufactured.

  The present invention according to claim 7 includes a step of forming a sacrificial film on a substrate, a step of forming a first electrode that covers the sacrificial film and is supported on the substrate, and the first electrode. Forming a piezoelectric film thereon; forming a second electrode on the piezoelectric film; and removing the sacrificial film to form a space between the substrate and the first electrode. And a step of forming a hole reaching the substrate surface at a central portion where the space is formed and the hole is brought into contact with the substrate surface when the sacrificial film is formed. And a step of forming a heat dissipation part by embedding a heat conductor, wherein the first electrode is formed so as to be in contact with the heat dissipation part.

  In the present invention according to claim 7, a step of forming a hole reaching the substrate surface in a central portion where the space is formed, a step of forming a heat radiating portion by embedding a heat conductor so as to contact the substrate surface in the hole, and Since the first electrode is formed so as to be in contact with the heat radiating portion, the heat generated in the resonator is radiated to the substrate side, so that the resonator has high heat dissipation characteristics, and the resonator is burned out. A resonator to be prevented is manufactured.

According to an eighth aspect of the present invention, a periphery is supported on the substrate, including a step of forming a recess in the substrate, a step of forming a sacrificial film filling the recess , and the substrate including the sacrificial film. Forming the first electrode; forming a piezoelectric film on the first electrode; forming a second electrode on the piezoelectric film; and removing the sacrificial film filling the concave portion to remove the substrate And a step of forming a space between the first electrode and the first electrode, wherein when the recess is formed, the heat sink is formed by leaving the substrate at the center of the recess. And when forming the said 1st electrode, it forms so that a said 1st electrode may contact the said thermal radiation part.

  In the present invention according to claim 8, when the space is formed, the heat radiating portion is formed by leaving the substrate in the central portion where the space is formed, and when the first electrode is formed, the first electrode is used as the heat radiating portion. Since they are formed so as to be in contact with each other, a resonator having high heat dissipation characteristics is produced, and a resonator that prevents burning of the resonator is manufactured.

According to an eleventh aspect of the present invention, there is provided a first electrode disposed on a substrate with a space around the substrate , a piezoelectric film formed on the first electrode, and the piezoelectric film. In a communication device equipped with a filter having a resonator including a resonator having a second electrode formed thereon, a heat radiating portion in contact with the substrate and the first electrode is provided at a central portion of the space. It is characterized by being.

  In the present invention according to claim 11, since the filter having the resonator of the present invention is mounted, it becomes possible to mount a highly reliable filter with improved heat dissipation, and the reliability of the communication device is increased. It is done.

  According to the first aspect of the present invention, since the heat dissipating part for dissipating the heat generated in the resonator to the substrate side is provided, the heat dissipating property of the resonator can be greatly increased, so that the burnout of the resonator can be prevented. Thus, there is an advantage that the reliability of the resonator can be improved. In addition, there is an advantage that high power can be applied to the resonator and the power durability is improved.

  According to the sixth aspect of the present invention, since the heat radiating portion for radiating the heat generated in the resonator to the substrate side is formed, the heat radiation property of the resonator can be greatly improved, so that the burnout of the resonator is prevented. As a result, the reliability of the resonator can be improved. In addition, there is an advantage that high power can be applied to the resonator and the power durability is improved.

  According to the seventh aspect of the present invention, since the heat radiating portion for radiating the heat generated in the resonator to the substrate side is formed, the heat radiation property of the resonator can be greatly improved, so that the burnout of the resonator is prevented. As a result, the reliability of the resonator can be improved. In addition, there is an advantage that high power can be applied to the resonator and the power durability is improved.

  According to the eighth aspect of the present invention, since the heat radiating portion for radiating the heat generated in the resonator to the substrate side is formed, the heat radiation property of the resonator can be greatly increased, so that the burnout of the resonator is prevented. As a result, the reliability of the resonator can be improved. In addition, there is an advantage that high power can be applied to the resonator and the power durability is improved.

  According to the eleventh aspect of the present invention, since the filter having the resonator according to the present invention is mounted, it is possible to mount a highly reliable filter with improved heat dissipation, and the reliability of the communication device. There is an advantage that can be enhanced.

  An embodiment (first embodiment) relating to the resonator of the present invention will be described with reference to the schematic sectional view of FIG. In FIG. 1, a membrane type resonator (FBAR) is shown as an example.

  As shown in FIG. 1, a first electrode (lower electrode) 13 is formed so as to cover a space 12 provided on the upper surface of the substrate 11. That is, the space 12 is enclosed by the first electrode 13, and the periphery of the first electrode 13 is supported by the substrate 11. The first electrode 13 is made of, for example, molybdenum (Mo) and has a thickness of, for example, 230 nm. For the first electrode 13, in addition to molybdenum, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used. The first electrode 13 may be formed of a plurality of layers of electrode material. The substrate 11 can be, for example, a semiconductor substrate, a substrate on which a semiconductor layer is formed, and a silicon semiconductor substrate is used here as an example.

  A piezoelectric film 14 is formed on the first electrode 13. Therefore, the piezoelectric film 13 is also formed above the space 12. The piezoelectric film 14 is an aluminum nitride (AlN) film, for example, and has a thickness of 1.0 μm, for example. Since the resonance frequency of the resonator (acoustic resonator) 1 is substantially determined by the film thickness of the piezoelectric film 14, the film thickness of the piezoelectric film 14 is determined according to the resonance frequency of the resonator 1.

  Further, in order for the piezoelectric film 14 to obtain sufficient piezoelectric characteristics, an aluminum nitride (AlN) layer is oriented in the c-axis direction as much as possible. For example, the allowable value is preferably within 1.5 degrees as the half-value width in the c-axis direction.

  A second electrode 15 is formed on the piezoelectric film 14 so as to cover the space 12. The second electrode 15 is made of, for example, molybdenum (Mo), and has a thickness of, for example, 334 nm. For the second electrode 15, in addition to molybdenum, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used. The second electrode 15 may be formed of a plurality of layers of electrode material. As described above, the first electrode 13, the piezoelectric film 14, and the second electrode 15 constitute a resonator 16.

  In addition, an extraction electrode 17 for the first electrode 13 is formed through a connection hole 31 formed in the piezoelectric film 14. A via hole 32 that reaches the space 12 through the piezoelectric film 14 and the first electrode 13 is formed. The via hole 32 is used when etching a sacrificial film (not shown) for forming the space 12 as will be described in detail later in the description of the manufacturing method.

  A heat radiating portion 18 for radiating heat generated by the resonator 16 to the substrate 11 side is formed at the center of the space 12. The heat radiating portion 18 is formed of a part of the resonator 16 and is formed so as to be in contact with the surface of the substrate 11. For example, the heat radiating portion 18 is formed in an inverted truncated cone shape by the resonator 16.

  As described above, the so-called air bridge type resonator (FBAR) 1 is configured.

  In the resonator 1, since the heat radiating portion 18 for radiating the heat generated in the resonator 16 to the substrate 11 side is formed in the central portion of the space 12, the central portion of the resonator 16 that is most likely to store heat. Since the heat generated in the resonator 16 is efficiently radiated from the heat sink 18 to the substrate 11 side, the heat radiation characteristics of the resonator 1 are improved, and the resonator 16 can be prevented from being burned out. There is an advantage that the reliability of the device 1 can be improved. In addition, it is possible to apply a large amount of power to the resonator 16 and there is an advantage that the power durability is improved.

  Next, an embodiment (second example) relating to the resonator of the present invention will be described with reference to the schematic sectional view of FIG. In FIG. 2, a membrane type resonator (FBAR) is shown as an example.

  As shown in FIG. 2, a first electrode (lower electrode) 13 is formed so as to cover a space 12 provided on the upper surface of the substrate 11. That is, the space 12 is enclosed by the first electrode 13, and the periphery of the first electrode 13 is supported by the substrate 11. The first electrode 13 is made of, for example, molybdenum (Mo) and has a thickness of, for example, 230 nm. For the first electrode 13, in addition to molybdenum, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used. The first electrode 13 may be formed of a plurality of layers of electrode material. The substrate 11 can be, for example, a semiconductor substrate, a substrate on which a semiconductor layer is formed, and a silicon semiconductor substrate is used here as an example.

  A piezoelectric film 14 is formed on the first electrode 13. Therefore, the piezoelectric film 14 is also formed above the space 12. The piezoelectric film 14 is an aluminum nitride (AlN) film, for example, and has a thickness of 1.0 μm, for example. Since the resonance frequency of the resonator (acoustic resonator) 2 is substantially determined by the film thickness of the piezoelectric film 14, the film thickness of the piezoelectric film 14 is determined according to the resonance frequency of the resonator 2.

  Further, in order for the piezoelectric film 14 to obtain sufficient piezoelectric characteristics, an aluminum nitride (AlN) layer is oriented in the c-axis direction as much as possible. For example, the allowable value is preferably within 1.5 degrees as the half-value width in the c-axis direction.

  A second electrode 15 is formed on the piezoelectric film 14 so as to cover the space 12. The second electrode 15 is made of, for example, molybdenum (Mo), and has a thickness of, for example, 334 nm. For the second electrode 15, in addition to molybdenum, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used. The second electrode 15 may be formed of a plurality of layers of electrode material. As described above, the first electrode 13, the piezoelectric film 14, and the second electrode 15 constitute a resonator 16.

  In addition, an extraction electrode 17 for the first electrode 13 is formed through a connection hole 31 formed in the piezoelectric film 14. A via hole 32 that reaches the space 12 through the piezoelectric film 14 and the first electrode 13 is formed. The via hole 32 is used when etching a sacrificial film (not shown) for forming the space 12 as will be described in detail later in the description of the manufacturing method.

  A heat radiating portion 19 that radiates heat generated by the resonator 16 to the substrate 11 side is formed in contact with the first electrode 13 and the surface of the substrate 11 at the center of the space 12. The heat dissipating part 19 is made of a heat conductor, for example, a material having a thermal conductivity equal to or higher than that of the first electrode 13, such as aluminum, copper, gold, silver, tungsten, molybdenum, etc. Made of good metal material. The heat dissipating part 19 is, for example, a columnar shape, a truncated cone shape, an inverted frustoconical shape, etc. so that the heat generated in the resonator 16 can be easily released to the substrate 11 side and stress is not applied to one point of the resonator 16. As described above, it is preferable that the contact portion with the resonator 16 is formed in such a shape that no corner portion is generated.

  As described above, the so-called air bridge type resonator (FBAR) 2 is configured.

  In the resonator 2, since the heat radiating portion 19 that radiates heat generated in the resonator 16 to the substrate 11 side is formed in the central portion of the space 12, heat is radiated from the central portion of the resonator 16 that is most likely to store heat. Since the heat generated in the resonator 16 is efficiently radiated to the substrate 11 side through the portion 19, the heat dissipation characteristics of the resonator 2 are improved, and the resonator 16 can be prevented from being burned out. There is an advantage that the reliability can be improved. In addition, it is possible to apply a large amount of power to the resonator 16 and there is an advantage that the power durability is improved.

  Next, an embodiment (third example) relating to the resonator of the present invention will be described with reference to FIG. In FIG. 3, a membrane type resonator (FBAR) is shown as an example, a schematic configuration sectional view is shown in (1) of FIG. 3, and a layout diagram is shown in (2).

  As shown in FIG. 3, a first electrode (lower electrode) 13 is formed so as to cover a space 12 formed on the upper surface side of the substrate 11. That is, the space 12 is covered by the first electrode 13, and the periphery of the first electrode 13 is supported on the substrate 11 around the space 12. The first electrode 13 is made of, for example, molybdenum (Mo) and has a thickness of, for example, 230 nm. For the first electrode 13, in addition to molybdenum, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used. The first electrode 13 may be formed of a plurality of layers of electrode material. The substrate 11 can be, for example, a semiconductor substrate, a substrate on which a semiconductor layer is formed, and a silicon semiconductor substrate is used here as an example.

  A piezoelectric film 14 is formed on the first electrode 13. Therefore, the piezoelectric film 14 is also formed above the space 12. The piezoelectric film 14 is an aluminum nitride (AlN) film, for example, and has a thickness of 1.0 μm, for example. Since the resonance frequency of the resonator (acoustic resonator) 3 is substantially determined by the film thickness of the piezoelectric film 14, the film thickness of the piezoelectric film 14 is determined according to the resonance frequency of the resonator 3.

  Further, in order for the piezoelectric film 14 to obtain sufficient piezoelectric characteristics, an aluminum nitride (AlN) layer is oriented in the c-axis direction as much as possible. For example, the allowable value is preferably within 1.5 degrees as the half-value width in the c-axis direction.

  A second electrode 15 is formed on the piezoelectric film 14 so as to cover the space 12. The second electrode 15 is made of, for example, molybdenum (Mo), and has a thickness of, for example, 334 nm. For the second electrode 15, in addition to molybdenum, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used. The second electrode 15 may be formed of a plurality of layers of electrode material. As described above, the first electrode 13, the piezoelectric film 14, and the second electrode 15 constitute a resonator 16.

  In addition, an extraction electrode 17 for the first electrode 13 is formed through a connection hole 31 formed in the piezoelectric film 14. A via hole 32 that reaches the space 12 through the piezoelectric film 14 and the first electrode 13 is formed. The via hole 32 is used when etching a sacrificial film (not shown) for forming the space 12 as will be described in detail later in the description of the manufacturing method.

  In the central portion of the space 12, a heat radiating portion 20 for radiating heat generated in the resonator 16 toward the substrate 11 is formed on the substrate 11 so as to come into contact with the first electrode 13. Therefore, since the heat radiating portion 20 is made of silicon, for example, when molybdenum is used for the first electrode 13, the thermal conductivity is higher than that of the first electrode 13. In addition, the first electrode 13 is made of a metal having higher thermal conductivity than the heat radiating portion 20 so that the heat generated by the resonator 16 can be easily released to the substrate 11 side by the heat radiating portion 20. Preferably it is. Further, the heat radiating portion 20 does not cause a corner portion in contact with the resonator 16 such as a columnar shape, a truncated cone shape, or an inverted truncated cone shape so that no stress is applied to one point of the resonator 16. It is preferable to be formed in a simple shape.

  As described above, the so-called air bridge type resonator (FBAR) 3 is configured.

  In the resonator 3, since the heat radiating portion 20 for radiating the heat generated in the resonator 16 to the substrate 11 side is formed in the central portion of the space 12, the central portion of the resonator 16 that is most likely to store heat. Since the heat generated in the resonator 16 is efficiently radiated from the heat sink 20 to the substrate 11 side, the heat dissipation characteristics of the resonator 3 are improved, and the resonator 16 can be prevented from being burned out. There is an advantage that the reliability of the device 3 can be improved. In addition, it is possible to apply a large amount of power to the resonator 16 and there is an advantage that the power durability is improved.

  Next, an embodiment (fourth example) relating to the resonator of the present invention will be described with reference to the schematic sectional view of FIG. FIG. 4 shows, as an example, an improved type of the resonator 2 described with reference to FIG.

  As shown in FIG. 4, a first electrode (lower electrode) 13 is formed so as to cover a space 12 provided on the upper surface of the substrate 11. That is, the space 12 is enclosed by the first electrode 13, and the periphery of the first electrode 13 is supported by the substrate 11. The first electrode 13 is made of, for example, molybdenum (Mo) and has a thickness of, for example, 230 nm. For the first electrode 13, in addition to molybdenum, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used. The first electrode 13 may be formed of a plurality of layers of electrode material. The substrate 11 can be, for example, a semiconductor substrate, a substrate on which a semiconductor layer is formed, and a silicon semiconductor substrate is used here as an example.

  A piezoelectric film 14 is formed on the first electrode 13. Therefore, the piezoelectric film 14 is also formed above the space 12. The piezoelectric film 14 is an aluminum nitride (AlN) film, for example, and has a thickness of 1.0 μm, for example. Since the resonance frequency of the resonator (acoustic resonator) 4 is substantially determined by the film thickness of the piezoelectric film 14, the film thickness of the piezoelectric film 14 is determined according to the resonance frequency of the resonator 4.

  Further, in order for the piezoelectric film 14 to obtain sufficient piezoelectric characteristics, an aluminum nitride (AlN) layer is oriented in the c-axis direction as much as possible. For example, the allowable value is preferably within 1.5 degrees as the half-value width in the c-axis direction.

  A second electrode 15 is formed on the piezoelectric film 14 so as to cover the space 12. The second electrode 15 is made of, for example, molybdenum (Mo), and has a thickness of, for example, 334 nm. For the second electrode 15, in addition to molybdenum, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used. The second electrode 15 may be formed of a plurality of layers of electrode material. As described above, the first electrode 13, the piezoelectric film 14, and the second electrode 15 constitute a resonator 16.

  In addition, an extraction electrode 17 for the first electrode 13 is formed through a connection hole 31 formed in the piezoelectric film 14. A via hole 32 that reaches the space 12 through the piezoelectric film 14 and the first electrode 13 is formed. The via hole 32 is used when etching a sacrificial film (not shown) for forming the space 12 as will be described in detail later in the description of the manufacturing method.

  A heat radiating portion 19 that radiates heat generated by the resonator 16 to the substrate 11 side is formed in contact with the first electrode 13 and the surface of the substrate 11 at the center of the space 12. The heat dissipating part 19 is made of a heat conductor, for example, a material having a thermal conductivity equal to or higher than that of the first electrode 13, such as aluminum, copper, gold, silver, tungsten, molybdenum, etc. Made of good metal material. The heat dissipating part 19 is, for example, a columnar shape, a truncated cone shape, an inverted frustoconical shape, etc. so that the heat generated in the resonator 16 can be easily released to the substrate 11 side and stress is not applied to one point of the resonator 16. As described above, it is preferable that the contact portion with the resonator 16 is formed in such a shape that no corner portion is generated.

  Furthermore, a heat radiating via 21 that contacts the heat radiating portion 19 is formed on the substrate 11. The heat radiating via 21 is preferably formed of a material having a thermal conductivity higher than that of the heat radiating portion 19. For example, the heat radiating via 21 is formed of a metal material having a good thermal conductivity such as aluminum, copper, gold, silver, tungsten, and molybdenum. Has been. The shape of the heat dissipation via 21 is not particularly limited.

  As described above, the so-called air bridge type resonator (FBAR) 4 is configured.

  In the resonator 4, the operational effect of the resonator 2 is obtained, and the heat radiation via 21 is provided in the substrate 11, so that the heat radiated by the heat radiation portion 19 is further easily radiated to the outside of the substrate 11. There is. As a result, the heat dissipation characteristics of the resonator 4 are further improved, and the resonator 16 can be prevented from being burned out. Thus, there is an advantage that the reliability of the resonator 4 can be improved. Further, it is possible to apply a larger amount of electric power to the resonator 16 and there is an advantage that the power durability is improved.

  The configuration in which the heat dissipation via 21 is provided on the substrate 11 can be applied to the resonator 1 described with reference to FIG. 1 and the resonator 3 described with reference to FIG. When applied to the resonator 1, it is the same as the resonator 2. When applied to the resonator 3, the heat dissipation via 21 is provided instead of the heat dissipation portion 20.

  Next, an embodiment (fifth example) relating to a method for manufacturing a resonator according to the present invention will be described with reference to the manufacturing process sectional views of FIGS. 5 to 7 show, as an example, a manufacturing process of the resonator 1 described with reference to FIG.

  As shown in FIG. 5A, a sacrificial film for forming a space in a later process is formed on the upper surface of the substrate 11. This sacrificial film consists of two layers. First, a first sacrificial film 41 is formed on the substrate 11. The first sacrificial film 41 is made of, for example, a silicon oxide film, and is formed by, for example, chemical vapor deposition.

  Next, as shown in FIG. 5B, a second sacrificial film 42 is formed on the first sacrificial film 41. The second sacrificial film 42 is made of, for example, a silicon oxide film, and is formed, for example, by applying SOG (Spin on glass) or baking. Hereinafter, the first sacrificial film 41 and the second sacrificial film 42 are collectively referred to as a sacrificial film 43. The sacrificial film 43 is formed to have a thickness of a space to be formed later.

  Next, as shown in FIG. 5 (3), a resist mask 44 for leaving a sacrificial film in a space forming region is formed by normal resist coating, lithography technology (resist exposure, resist development, etc.), and resist baking. To do. In the resist mask 44, a hole 45 for forming a region to be a heat radiating portion is formed at the same time.

  Next, as shown in FIG. 5 (4), the sacrificial film 43 is patterned by an etching technique using the resist mask 44, and a sacrificial film pattern 46 in which holes 47 are formed in a region where a heat radiating portion is formed. Form. The sacrificial film pattern 46 is formed in a truncated cone shape, for example. The sacrificial film pattern 46 is preferably formed of, for example, a silicon oxide film that can be etched with, for example, hydrofluoric acid. Therefore, in addition to the above-described SOG film and silicon oxide film formed by chemical vapor deposition, it can also be formed of a phosphorous silicate glass (PSG) film, a boron phosphorous silicate glass (BPSG) film, or the like.

  Next, as shown in FIG. 5 (5), a first electrode formation film 48 is formed on the substrate 11 so as to cover the sacrificial film pattern 46. At this time, the first electrode formation film 48 is also formed on the inner surface of the hole 47. The first electrode formation film 48 is formed by depositing, for example, molybdenum (Mo) to a thickness of 230 nm, for example, by a DC magnetron sputtering method or the like. For the first electrode formation film 48, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, and copper can be used in addition to molybdenum. The first electrode formation film 48 may be formed of a plurality of layers of electrode material.

  Next, as shown in FIG. 6 (6), the first electrode 13 is formed by patterning the first electrode formation film 48 by ordinary resist coating, lithography, etching, or the like. The first electrode 13 is in contact with the substrate 11 through the hole 47.

  Next, as shown in FIG. 6 (7), the piezoelectric film 14 is formed so as to cover the first electrode 13. The piezoelectric film 14 is an aluminum nitride (AlN) film, for example, with a thickness of 1.0 μm, for example, by a DC pulse sputtering method or the like. Since the resonance frequency of the resonator (FBAR) is substantially determined by the film thickness of the piezoelectric film 14, the film thickness of the piezoelectric film 14 is determined according to the resonance frequency of the resonator.

  Next, as shown in FIG. 6 (8), the piezoelectric film 14 is patterned by normal resist coating, lithography technique, etching technique or the like to form a connection hole 31 leading to the first electrode 13.

  Next, as shown in FIG. 6 (9), a second electrode formation film 49 is formed on the piezoelectric film 14. At this time, the second electrode formation film 49 is connected to the first electrode 13 through the connection hole 31. The second electrode formation film 49 is formed by depositing, for example, molybdenum (Mo) to a thickness of, for example, 334 nm by, for example, DC magnetron sputtering. For the second electrode formation film 49, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used in addition to molybdenum. The second electrode formation film 49 can also be formed of a plurality of layers of electrode material.

  Next, as shown in FIG. 7 (10), a resist mask (not shown) for forming the second electrode and the extraction electrode is formed by normal resist coating and lithography techniques, and then this resist mask is used. The second electrode formation film 49 is patterned by an etching technique to form the extraction electrode 17 connected to the second electrode 15 and the first electrode 13 through the connection hole 31. For example, this etching is performed by reactive ion etching (RIE) using a halogen-based gas as an etching gas. Thereafter, the resist mask is removed.

  Next, as shown in FIG. 7 (11), after forming a resist mask (not shown) for forming a via hole necessary for removing the sacrificial film pattern 46 by resist coating and lithography techniques, By this etching technique using a resist mask, a via hole 32 that penetrates the piezoelectric film 14 and the first electrode 13 and reaches the sacrificial film pattern 46 is formed. For example, this etching is performed by reactive ion etching (RIE) using a halogen-based gas as an etching gas.

  Next, as shown in FIG. 7 (12), the resist mask is removed. Thereafter, the sacrificial film pattern 46 [see FIG. 7 (11)] is removed through the via hole 32. The sacrificial film pattern 46 is removed by wet etching using a hydrofluoric acid (HF) aqueous solution 50, for example. By this etching, the sacrificial film pattern 46 is completely removed, and a space 12 is formed in the removed portion.

  As a result, the space 12 is formed between the substrate 11 and the first electrode 13 as shown in FIG. In this way, the resonator 16 including the first electrode 13, the piezoelectric film 14, and the second electrode 15 is provided on the substrate 11 via the space 12, and a part of the resonator 16 is formed at the center of the space 12. An air bridge type resonator (FBAR) 1 having a heat radiating portion 18 in contact with or connected to the substrate 11 is completed.

  When the sacrificial film 43 is formed, the resonator 1 is manufactured by forming the hole 47 reaching the surface of the substrate 11 at the center where the space 12 is formed, and forming the first electrode 13. The electrode 13 is formed in contact with the surface of the substrate 11, and heat generated by the resonator (first electrode 13, piezoelectric film 14 and second electrode 15) 16 is radiated to the substrate 11 side in the center of the space 12. Since the heat dissipating part 18 is formed, there is an advantage that the resonator 1 having excellent heat dissipation of the resonator 16 and capable of preventing the resonator 16 from being burned out and having high reliability can be manufactured. In addition, a large amount of power can be applied to the resonator 16, and an improvement in power durability can be obtained.

  Next, an embodiment (sixth example) relating to a method of manufacturing a resonator according to the present invention will be described with reference to a manufacturing process sectional view of FIG. FIG. 8 shows, as an example, a manufacturing process of the resonator 2 described with reference to FIG.

  As shown in FIG. 8 (1), the first sacrificial film 41 and the second sacrificial film 42 are formed on the substrate 11 by performing the steps described with reference to FIG. 5 (1) to FIG. 5 (4). Thus, a sacrificial film pattern 46 having a hole 47 is formed in a region where the heat radiating portion is formed. The sacrificial film pattern 46 is formed in a truncated cone shape, for example, and a hole 47 is formed at the center thereof. The sacrificial film pattern 46 is preferably formed of, for example, a silicon oxide film that can be etched with, for example, hydrofluoric acid. Therefore, in addition to the above-described SOG film and silicon oxide film formed by chemical vapor deposition, it can be formed of a phosphorus silicate glass (PSG) film, a boron phosphorus silicate glass (BPSG) film, or the like.

  Next, as shown in FIG. 8 (2), the heat radiating portion 19 is formed inside the hole 47. Various methods can be adopted as a method of forming the heat radiating portion 19, and the heat radiating portion 19 may be formed only inside the hole 47. For example, after forming a material film for forming the heat dissipating part 19 so as to fill the hole 47 by sputtering, etching back or chemical mechanical polishing is performed so that the sacrificial film pattern 46 is exposed, and then the sacrificial film pattern 46 is surrounded. There is a method of removing the material film. Alternatively, there is a method in which a mask having an opening on the hole 47 is formed and the material film is selectively grown inside the hole 47 depending on the material of the heat radiation part. Alternatively, after a hole 47 is formed in the sacrificial film for forming the sacrificial film pattern 46, a material film for forming a heat radiation portion is formed so as to fill the hole 47 by sputtering, and an excessive material film on the sacrificial film is formed by, for example, chemical There is a method in which the heat radiating portion 19 is formed inside the hole 47 by removing by mechanical mechanical polishing, etch back or the like, and then the sacrificial film is patterned to form the sacrificial film pattern 46.

  Next, as shown in FIG. 8 (3), a first electrode formation film 48 is formed on the substrate 11 so as to cover the sacrificial film pattern 46. The first electrode formation film 48 is formed by depositing, for example, molybdenum (Mo) to a thickness of 230 nm, for example, by a DC magnetron sputtering method or the like. For the first electrode formation film 48, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, and copper can be used in addition to molybdenum. The first electrode formation film 48 may be formed of a plurality of layers of electrode material.

  Next, as shown in FIG. 8 (4), the piezoelectric film 14 covering the first electrode 13 is formed by performing the steps described with reference to FIGS. 6 (6) to 7 (12). The piezoelectric film 14 is an aluminum nitride (AlN) film, for example, with a thickness of 1.0 μm, for example, by a DC pulse sputtering method or the like. Since the resonance frequency of the resonator (FBAR) is substantially determined by the film thickness of the piezoelectric film 14, the film thickness of the piezoelectric film 14 is determined according to the resonance frequency of the resonator.

  Next, the connection hole 31 leading to the first electrode 13 is formed by patterning the piezoelectric film 14 by ordinary resist coating, lithography technique, etching technique or the like.

  Next, a second electrode forming film 49 is formed on the piezoelectric film 14. The second electrode formation film 49 is formed by depositing, for example, molybdenum (Mo) to a thickness of, for example, 334 nm by, for example, DC magnetron sputtering. For the second electrode formation film 49, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used in addition to molybdenum. The second electrode formation film 49 can also be formed of a plurality of layers of electrode material.

  Next, after forming a resist mask (not shown) for forming the second electrode and the extraction electrode of the first electrode by a normal resist coating and lithography technique, the above-described first etching technique using the resist mask is performed. The two-electrode formation film 49 is patterned to form the extraction electrode 17 for the first electrode 13 connected to the second electrode 15 and the first electrode 13 through the connection hole 31. For example, this etching is performed by reactive ion etching (RIE) using a halogen-based gas as an etching gas. Thereafter, the resist mask is removed.

  Next, a resist mask (not shown) for forming a via hole necessary for removing the sacrificial film pattern 46 [see FIG. 8 (3)] is formed by resist coating and lithography techniques, Via holes 32 that penetrate the piezoelectric film 14 and the first electrode 13 and reach the sacrificial film pattern 46 are formed by an etching technique using a resist mask. For example, this etching is performed by reactive ion etching (RIE) using a halogen-based gas as an etching gas.

  Next, the resist mask is removed. Thereafter, the sacrificial film pattern 46 [see FIG. 8 (3)] is removed through the via hole 32. The sacrificial film pattern 46 is removed by, for example, wet etching using a hydrofluoric acid (HF) aqueous solution. By this etching, the sacrificial film pattern 46 is completely removed, and a space 12 is formed in the removed portion.

  As a result, the space 12 is formed between the substrate 11 and the first electrode 13. In this way, the resonator 16 including the first electrode 13, the piezoelectric film 14, and the second electrode 15 is provided on the substrate 11 via the space 12, and the resonator 16, the substrate 11, The air bridge type resonator (FBAR) 2 in which the heat dissipating part 19 that contacts or is connected to is formed.

  In the method for manufacturing the resonator 2, the hole 47 reaching the surface of the substrate 11 is formed in the center of the sacrificial film pattern 46, the heat dissipating part 19 is formed so as to fill the hole 47, and the first electrode 13 is formed. In addition, since the first electrode 13 is formed so as to be in contact with the heat radiating part 19, when the space 12 is formed, a resonator (first electrode 13, piezoelectric film 14 and second electrode 15) Since the heat dissipating part 19 that dissipates the heat generated in 16 to the substrate 11 side is formed, it is possible to manufacture the highly reliable resonator 2 that is excellent in the heat dissipating property of the resonator 16 and can prevent the resonator 16 from being burned out. There is an advantage. In addition, a large amount of power can be applied to the resonator 16, and an improvement in power durability can be obtained.

  Next, an embodiment (seventh example) relating to a method for manufacturing a resonator according to the present invention will be described with reference to the manufacturing process cross-sectional views of FIGS. 9 to 11 show, as an example, a manufacturing process of the resonator 3 described with reference to FIG.

  As shown in FIG. 9A, after a resist mask (not shown) used for forming a space in the substrate 11 is formed by resist coating and lithography technology, the substrate 11 is etched by this etching technique using the resist mask. A space 12 is formed. At that time, the heat radiating portion 20 is formed by leaving a part of the substrate 11 in the center of the space 12. The space 12 is formed to a depth that does not contact the substrate 11 when the resonator vibrates, for example, a depth of 1.0 μm.

  Next, as shown in FIG. 9B, a first sacrificial film 41 is formed on the surface of the substrate 11 so as to fill the space 12. The first sacrificial film 41 is formed of, for example, a silicon oxide film, and is formed by, for example, chemical vapor deposition.

  Next, as shown in FIG. 9 (3), the second sacrificial film 42 is formed on the first sacrificial film 41, and the space 12 is completely formed by the sacrificial film 43 including the first sacrificial film 41 and the second sacrificial film 42. Embed in. The second sacrificial film 42 is made of, for example, a silicon oxide film, and is formed, for example, by applying SOG (Spin on glass) or baking. Hereinafter, the first sacrificial film 41 and the second sacrificial film 42 are collectively referred to as a sacrificial film 43. The sacrificial film 43 is preferably formed of, for example, a silicon oxide film that can be etched with, for example, hydrofluoric acid. Therefore, in addition to the above-described SOG film and silicon oxide film formed by chemical vapor deposition, it can also be formed of a phosphorous silicate glass (PSG) film, a boron phosphorous silicate glass (BPSG) film, or the like.

  Next, as shown in FIG. 9 (4), the excess sacrificial film 43 on the substrate 11 is removed to leave the sacrificial film 43 inside the space 12. For this removal processing, for example, techniques such as chemical mechanical polishing and etch back can be used.

  Next, as shown in FIG. 9 (5), a first electrode formation film 48 is formed on the substrate 11 including the sacrificial film 43. The first electrode formation film 48 is formed by depositing, for example, molybdenum (Mo) to a thickness of 230 nm, for example, by a DC magnetron sputtering method or the like. For the first electrode formation film 48, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, and copper can be used in addition to molybdenum. The first electrode formation film 48 may be formed of a plurality of layers of electrode material.

  Next, as shown in FIG. 10 (6), the first electrode forming film 48 is patterned by normal resist coating, lithography technique, etching technique, etc., and the first electrode 13 whose periphery is supported on the substrate 11 is patterned. Form. The first electrode 13 is in contact with the heat dissipation part 20.

  Next, as shown in FIG. 10 (7), a piezoelectric film 14 is formed on the substrate 11 so as to cover the first electrode 13. The piezoelectric film 14 is an aluminum nitride (AlN) film, for example, with a thickness of 1.0 μm, for example, by a DC pulse sputtering method or the like. Since the resonance frequency of the resonator (FBAR) is substantially determined by the film thickness of the piezoelectric film 14, the film thickness of the piezoelectric film 14 is determined according to the resonance frequency of the resonator.

  Next, as shown in FIG. 10 (8), a connection hole 31 for forming a take-out electrode connected to the first electrode 13 is formed in the piezoelectric film 14 by ordinary resist coating, lithography technique, etching technique or the like. To do.

  Next, as shown in FIG. 10 (9), a second electrode formation film 49 is formed on the piezoelectric film 14 including the inside of the connection hole 31. The second electrode formation film 49 is formed by depositing, for example, molybdenum (Mo) to a thickness of, for example, 334 nm by, for example, DC magnetron sputtering. For the second electrode formation film 49, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used in addition to molybdenum. The second electrode formation film 49 can also be formed of a plurality of layers of electrode material.

  Next, as shown in FIG. 11 (10), a resist mask (not shown) for forming the second electrode and the extraction electrode is formed by normal resist coating and lithography techniques, and then this resist mask is used. The second electrode forming film 49 is patterned by an etching technique to form the second electrode 15 so as to cover the region where the sacrificial film 43 is left, and the extraction electrode connected to the first electrode 13 through the connection hole 31 17 is formed. For example, this etching is performed by reactive ion etching (RIE) using a halogen-based gas as an etching gas. Thereafter, the resist mask is removed.

  Next, as shown in FIG. 11 (11), a resist mask (not shown) for forming a via hole necessary for removing the sacrificial film 43 is formed by resist coating and lithography techniques, Via holes 32 that penetrate the piezoelectric film 14 and the first electrode 13 and reach the sacrificial film 43 are formed by an etching technique using a resist mask. For example, this etching is performed by reactive ion etching (RIE) using a halogen-based gas as an etching gas.

  Next, as shown in FIG. 11 (12), the resist mask is removed. Thereafter, the sacrificial film 43 [see FIG. 11 (11)] is removed through the via hole 32. For example, the sacrificial film 43 is removed by wet etching using a hydrofluoric acid (HF) aqueous solution 50. By this etching, the sacrificial film 43 is completely removed, and the space 12 appears in the removed portion, and the heat radiating portion 20 that leaves the substrate 11 in the center where the space 12 is formed appears.

  As a result, as shown in FIG. 11 (13), the heat radiating portion 20 is formed between the substrate 11 and the first electrode 13 in the central portion of the space 12 formed in the substrate 11. In this way, the resonator 16 including the first electrode 13, the piezoelectric film 14, and the second electrode 15 is provided on the substrate 11 via the space 12, and a part of the resonator 16 is formed at the center of the space 12. An air bridge type resonator (FBAR) 3 in contact with the heat radiating portion 20 made of the substrate 11 is completed.

  The manufacturing method of the resonator 3 includes the substrate 11 at the center of the space 12 when the space 12 is formed in the substrate 11. The resonator (first electrode 13, piezoelectric film 14 and second electrode 15) Since the heat radiating part 20 for radiating the heat generated in the substrate 16 to the substrate 11 side is formed, the highly reliable resonator 3 that is excellent in the heat dissipation of the resonator 16 and can prevent the resonator 16 from being burned out. There is an advantage that it can be manufactured. In addition, a large amount of power can be applied to the resonator 16, and an improvement in power durability can be obtained.

  Next, an embodiment (eighth example) relating to a method of manufacturing a resonator according to the present invention will be described with reference to manufacturing process cross-sectional views of FIGS. 12 to 13 show, as an example, a manufacturing process of the resonator 4 described with reference to FIG.

  As shown in FIG. 12A, a sacrificial film for forming a space in a later step is formed on the upper surface of the substrate 11. This sacrificial film consists of two layers. First, a first sacrificial film 41 is formed on the substrate 11. The first sacrificial film 41 is made of, for example, a silicon oxide film, and is formed by, for example, chemical vapor deposition.

  Next, as shown in FIG. 12 (2), a second sacrificial film 42 is formed on the first sacrificial film 41. The second sacrificial film 42 is made of, for example, a silicon oxide film, and is formed, for example, by applying SOG (Spin on glass) or baking. Hereinafter, the first sacrificial film 41 and the second sacrificial film 42 are collectively referred to as a sacrificial film 43. Since the sacrificial film 43 has a depth of a space to be formed later, the sacrificial film 43 is formed to a thickness that does not contact the substrate 11 when the resonator vibrates, for example, a thickness of 1 μm.

  Next, as shown in FIG. 12 (3), a resist mask (not shown) used for forming a heat dissipation via is formed on the substrate 11 by resist coating and lithography techniques, and then an etching technique using this resist mask. Thus, a via hole 22 for forming a heat dissipation via is formed in the substrate 11. The via hole 22 is formed so as to be directly under a heat radiating portion formed in a later process. Next, after forming a heat-dissipating via formation film for embedding the via hole 22 by an embedding technique such as plating, the excess heat-dissipating via-forming film on the substrate 11 is removed, and heat dissipation is performed by the heat-dissipating via-forming film remaining in the via hole 22. A via 21 is formed.

  Next, as shown in FIG. 12 (4), a resist mask 44 for leaving a sacrificial film in a space forming region is formed by normal resist coating, lithography technology (resist exposure, resist development, etc.), and resist baking. To do. In the resist mask 44, a hole 45 for forming a region to be a heat radiating portion is formed at the same time. The sacrificial film 43 is etched using the resist mask 44.

  As a result, as shown in FIG. 13 (5), a sacrificial film pattern 46 in which holes 47 are formed in the region where the heat radiating portion is formed is formed. The sacrificial film pattern 46 is formed in a truncated cone shape, for example, and a hole 47 is formed at the center thereof. The sacrificial film pattern 46 is preferably formed of, for example, a silicon oxide film that can be etched with, for example, hydrofluoric acid. Therefore, in addition to the above-described SOG film and silicon oxide film formed by chemical vapor deposition, it can be formed of a phosphorus silicate glass (PSG) film, a boron phosphorus silicate glass (BPSG) film, or the like.

  Thereafter, the same process as described with reference to FIGS. 8 (2) to (4) is performed. That is, as shown in FIG. 13 (6), the heat radiating portion 19 is formed inside the hole 47. Various methods can be adopted as a method of forming the heat radiating portion 19, and the heat radiating portion 19 may be formed only inside the hole 47. For example, after forming a material film for forming the heat dissipating part 19 so as to fill the hole 47 by sputtering, etching back or chemical mechanical polishing is performed so that the sacrificial film pattern 46 is exposed, and then the sacrificial film pattern 46 is surrounded. There is a method of removing the material film. Alternatively, there is a method in which a mask having an opening on the hole 47 is formed and the material film is selectively grown inside the hole 47 depending on the material of the heat radiation part. Alternatively, after a hole 47 is formed in the sacrificial film for forming the sacrificial film pattern 46, a material film for forming a heat radiation portion is formed so as to fill the hole 47 by sputtering, and an excessive material film on the sacrificial film is formed by, for example, chemical There is a method in which the heat radiating portion 19 is formed inside the hole 47 by removing by mechanical mechanical polishing, etch back or the like, and then the sacrificial film is patterned to form the sacrificial film pattern 46.

  Next, as shown in FIG. 13 (7), a first electrode formation film 48 is formed on the substrate 11 so as to cover the sacrificial film pattern 46. The first electrode formation film 48 is formed by depositing, for example, molybdenum (Mo) to a thickness of 230 nm, for example, by a DC magnetron sputtering method or the like. For the first electrode formation film 48, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, and copper can be used in addition to molybdenum. The first electrode formation film 48 may be formed of a plurality of layers of electrode material.

  Next, as shown in FIG. 13 (8), a piezoelectric film 14 that covers the first electrode 13 is formed. The piezoelectric film 14 is an aluminum nitride (AlN) film, for example, with a thickness of 1.0 μm, for example, by a DC pulse sputtering method or the like. Since the resonance frequency of the resonator (FBAR) is substantially determined by the film thickness of the piezoelectric film 14, the film thickness of the piezoelectric film 14 is determined according to the resonance frequency of the resonator.

  Next, the connection hole 31 leading to the first electrode 13 is formed by patterning the piezoelectric film 14 by ordinary resist coating, lithography technique, etching technique or the like.

  Next, a second electrode forming film 49 is formed on the piezoelectric film 14. The second electrode formation film 49 is formed by depositing, for example, molybdenum (Mo) to a thickness of, for example, 334 nm by, for example, DC magnetron sputtering. For the second electrode formation film 49, a metal material such as tungsten, tantalum, titanium, platinum, ruthenium, gold, aluminum, or copper can be used in addition to molybdenum. The second electrode formation film 49 can also be formed of a plurality of layers of electrode material.

  Next, after forming a resist mask (not shown) for forming the second electrode and the extraction electrode of the first electrode by a normal resist coating and lithography technique, the above-described first etching technique using the resist mask is performed. The two-electrode formation film 49 is patterned to form the extraction electrode 17 for the first electrode 13 connected to the second electrode 15 and the first electrode 13 through the connection hole 31. For example, this etching is performed by reactive ion etching (RIE) using a halogen-based gas as an etching gas. Thereafter, the resist mask is removed.

  Next, a resist mask (not shown) for forming a via hole necessary for removing the sacrificial film pattern 46 [see FIG. 8 (3)] is formed by resist coating and lithography techniques, Via holes 32 that penetrate the piezoelectric film 14 and the first electrode 13 and reach the sacrificial film pattern 46 are formed by an etching technique using a resist mask. For example, this etching is performed by reactive ion etching (RIE) using a halogen-based gas as an etching gas.

  Next, the resist mask is removed. Thereafter, the sacrificial film pattern 46 [see FIG. 13 (7)] is removed through the via hole 32. The sacrificial film pattern 46 is removed by, for example, wet etching using a hydrofluoric acid (HF) aqueous solution. By this etching, the sacrificial film pattern 46 is completely removed, and a space 12 is formed in the removed portion.

  As a result, the space 12 is formed between the substrate 11 and the first electrode 13. In this manner, the resonator 16 including the first electrode 13, the piezoelectric film 14, and the second electrode 15 is provided on the substrate 11 via the space 12, and the resonator 16 and the substrate 11 are disposed at the center of the space 12. The air bridge type resonator (FBAR) 2 in which the heat dissipating part 19 that is in contact with or connected to the formed heat dissipating via 21 is formed is completed.

  In the method of manufacturing the resonator 4, the heat dissipation via 21 to which the heat dissipation portion 19 is connected is formed on the substrate 11, and therefore, the resonator 4 having better heat dissipation characteristics than the resonator 2 can be manufactured.

  The manufacturing method for forming the heat dissipation via 21 can also be applied to the manufacturing method of the resonator 1. In this case, the heat dissipation via 21 may be formed in the substrate 11 after the sacrificial film 43 is formed.

  Next, an example of an embodiment according to the communication apparatus of the present invention will be described with reference to the block diagram of FIG. The communication apparatus described in FIG. 14 includes a filter using any one of the resonators 1 to 4 of the present invention. This filter can be used as a high frequency (RF) filter, an intermediate frequency (IF) filter, or the like. The communication device including such a filter uses electromagnetic waves such as a mobile phone, a personal digital assistant (PDA) device, a wireless LAN device, a wireless transceiver, a television tuner, a radio tuner, and the like. There are communication devices that communicate with each other.

  As shown in FIG. 14, the configuration of the transmission system of the communication apparatus 200 will be described. This transmission system supplies, for example, I-channel transmission data to a digital / analog converter (DAC) 201I to convert it into an analog signal. Further, Q channel transmission data is supplied to a digital / analog converter (DAC) 201Q to be converted into an analog signal. The converted signal of each channel is supplied to band pass filters 202I and 202Q, signal components other than the band of the transmission signal are removed, and the outputs of the band pass filters 202I and 202Q are supplied to the modulator 210. To do.

  The modulator 210 supplies each channel to the mixers 212I and 212Q via the buffer amplifiers 211I and 211Q, and mixes the frequency signal corresponding to the transmission frequency supplied from the PLL (phase-locked loop) circuit 203 for transmission. Then, the two mixed signals are added by the adder 214 to form one transmission signal. In this case, the signal phase of the frequency signal supplied to the mixer 212I is shifted by 90 ° by the phase shifter 213 so that the I channel signal and the Q channel signal are orthogonally modulated.

  The output of the adder 214 is supplied to the power amplifier 204 via the buffer amplifier 215 and amplified so as to have a predetermined transmission power. The signal amplified by the power amplifier 204 is supplied to the antenna 207 via the transmission / reception switch 205 and the high frequency filter 206, and is wirelessly transmitted from the antenna 207. The high frequency filter 206 is a band pass filter that removes signal components other than the frequency band transmitted and received by the communication apparatus.

  As a configuration of the reception system, a signal received by the antenna 207 is supplied to the high frequency unit 220 via the high frequency filter 206 and the transmission / reception switch 205. The high frequency unit 220 amplifies the received signal with a low noise amplifier (LNA) 221, then supplies the amplified signal to the band pass filter 222 to remove signal components other than the received frequency band, and removes the signal component via the buffer amplifier 223. The obtained signal is supplied to the mixer 224. Then, the frequency signals supplied from the channel selection PLL circuit 251 are mixed to make a signal of a predetermined transmission channel an intermediate frequency signal, and the intermediate frequency signal is supplied to the intermediate frequency circuit 230 via the buffer amplifier 225.

  In the intermediate frequency circuit 230, the intermediate frequency signal supplied via the buffer amplifier 231 is supplied to the band pass filter 232 to remove signal components other than the band of the intermediate frequency signal, and the removed signal is automatically gained. The signal is supplied to an adjustment circuit (AGC circuit) 233 to obtain a signal with a substantially constant gain. The intermediate frequency signal whose gain has been adjusted by the automatic gain adjustment circuit 233 is supplied to the demodulator 240 via the buffer amplifier 234.

  The demodulator 240 supplies the intermediate frequency signal supplied via the buffer amplifier 241 to the mixers 242I and 242Q, mixes the frequency signal supplied from the intermediate frequency PLL circuit 252, and receives the received I channel signal. The component and the Q channel signal component are demodulated. In this case, the I-signal mixer 242I is supplied with a frequency signal whose signal phase is shifted by 90 ° by the phase shifter 243, and the quadrature-modulated I-channel signal component and Q-channel signal component. Is demodulated.

  The demodulated I channel and Q channel signals are supplied to band pass filters 253I and 253Q via buffer amplifiers 244I and 244Q, respectively, and signal components other than I channel and Q channel signals are removed and removed. The obtained signals are supplied to analog / digital converters (ADC) 254I and 254Q, sampled and converted into digital data, and I-channel received data and Q-channel received data are obtained.

  In the configuration described so far, band limiting is performed by applying the filter of the configuration of the above-described embodiment as a part or all of each band pass filter 202I, 202Q, 206, 222, 232, 253I, 253Q. Is possible.

  According to the communication device 200 of the present invention, since a stable DC bias voltage can be supplied to the electrostatically driven vibrator constituting the filter, temporal variation of the output high frequency signal and / or intermediate frequency signal is suppressed. In addition, the destruction of the vibrator due to the suddenly applied high voltage pulse (surge voltage) can be prevented, and a highly reliable communication device can be provided.

  In the above embodiment, each filter is configured as a band pass filter. However, a low pass filter that passes only a frequency band below a predetermined frequency, or only a frequency band above a predetermined frequency is used. The high-pass filters may be configured to pass, and the filters of the configurations of the above-described embodiments may be applied to these filters. In the example of FIG. 14, the communication device performs wireless transmission and reception. However, the communication device may be applied to a filter included in the communication device that performs transmission and reception via a wired transmission path. The filter having the configuration of the above-described embodiment may be applied to a filter included in a communication device that performs communication or a communication device that performs only reception processing.

  Since the communication device 200 according to the present invention is equipped with the filter having the resonator according to the present invention, it is possible to mount a highly reliable filter in which burnout of the resonator is prevented, and the reliability of the communication device is improved. There is an advantage that it can be increased.

1 is a schematic cross-sectional view showing an embodiment (first embodiment) relating to a resonator according to the present invention. It is a schematic structure sectional view showing one embodiment (the 2nd example) concerning a resonator of the present invention. FIG. 6 is a schematic cross-sectional view and layout diagram showing an embodiment (third embodiment) relating to the resonator of the present invention. FIG. 6 is a schematic cross-sectional view showing an embodiment (fourth example) relating to the resonator of the present invention. It is manufacturing process sectional drawing which showed one Embodiment (5th Example) regarding the manufacturing method of the resonator of this invention. It is manufacturing process sectional drawing which showed one Embodiment (5th Example) regarding the manufacturing method of the resonator of this invention. It is manufacturing process sectional drawing which showed one Embodiment (5th Example) regarding the manufacturing method of the resonator of this invention. It is manufacturing process sectional drawing which showed one Embodiment (6th Example) regarding the manufacturing method of the resonator of this invention. It is manufacturing process sectional drawing which showed one Embodiment (7th Example) regarding the manufacturing method of the resonator of this invention. It is manufacturing process sectional drawing which showed one Embodiment (7th Example) regarding the manufacturing method of the resonator of this invention. It is manufacturing process sectional drawing which showed one Embodiment (7th Example) regarding the manufacturing method of the resonator of this invention. It is manufacturing process sectional drawing which showed one Embodiment (8th Example) regarding the manufacturing method of the resonator of this invention. It is manufacturing process sectional drawing which showed one Embodiment (8th Example) regarding the manufacturing method of the resonator of this invention. It is a block diagram which shows an example of one Embodiment which concerns on the communication apparatus of this invention. It is a schematic structure sectional view showing an example of the conventional resonator. It is a schematic block diagram and a layout diagram showing an example of a heat dissipation path of a conventional resonator.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Resonator, 11 ... Board | substrate, 12 ... Space, 13 ... 1st electrode, 14 ... Piezoelectric film, 15 ... 2nd electrode, 16 ... Resonator, 18 ... Radiation part

Claims (11)

A first electrode disposed on the substrate via a space in a state where the periphery is supported by the substrate;
A piezoelectric film formed on the first electrode;
A resonator including a resonator having a second electrode formed on the piezoelectric film,
The resonator according to claim 1, wherein a heat radiating portion that contacts the substrate and the first electrode is provided at a central portion of the space . 2. The resonator according to claim 1, wherein the heat radiating portion is formed such that a part of the resonator is in contact with the surface of the substrate. The resonator according to claim 1, wherein the heat radiating portion is formed of a heat conductor that connects the surface of the substrate and the first electrode. The substrate has a recess to be the space ;
The heat dissipating part consists of the substrate part left in the central part of the recess,
The resonator according to claim 1, wherein the first electrode is formed so as to be in contact with the heat radiating portion. The resonator according to claim 1, wherein a heat radiating via contacting the heat radiating portion is formed on the substrate. Forming a sacrificial film for forming a space on the substrate;
Forming a first electrode covering the sacrificial film and having a periphery supported on the substrate;
Forming a piezoelectric film on the first electrode;
Forming a second electrode on the piezoelectric film;
A method of manufacturing a resonator comprising: removing the sacrificial film to form a space between the substrate and the first electrode;
When forming the sacrificial film, a hole reaching the substrate surface is formed in the center where the space is formed,
A method for manufacturing a resonator, comprising: forming the first electrode in contact with the substrate surface through the hole. Forming a sacrificial film on the substrate;
Forming a first electrode covering the sacrificial film and having a periphery supported on the substrate;
Forming a piezoelectric film on the first electrode;
Forming a second electrode on the piezoelectric film;
Removing the sacrificial film and forming a space between the substrate and the first electrode, comprising:
When forming the sacrificial film, a step of forming a hole reaching the substrate surface at a central portion where the space is formed, and a heat radiating portion is formed by embedding a thermal conductor in the hole so as to contact the substrate surface Comprising the steps of:
The method for manufacturing a resonator, wherein the first electrode is formed so as to be in contact with the heat radiating portion. Forming a recess in the substrate;
Forming a sacrificial film for embedding the recess ;
Forming a first electrode on the substrate including the sacrificial film, the periphery of which is supported on the substrate;
Forming a piezoelectric film on the first electrode;
Forming a second electrode on the piezoelectric film;
A step of removing the sacrificial film embedded in the recess and forming a space between the substrate and the first electrode,
When forming the concave portion , leaving the substrate in the central portion of the concave portion to form a heat radiating portion,
When forming the first electrode, the first electrode is formed so as to be in contact with the heat radiating portion. The method of manufacturing a resonator according to claim 6, wherein a heat radiating via is formed in the substrate at a position where the heat radiating portion is formed immediately after the sacrificial film is formed. The method for manufacturing a resonator according to claim 7, wherein a heat radiating via is formed in the substrate at a position where the heat radiating portion is formed immediately after the sacrificial film is formed. A first electrode surrounding is disposed through a space on the substrate while being supported by the substrate,
A piezoelectric film formed on the first electrode;
In a communication apparatus equipped with a filter having a resonator including a resonator having a second electrode formed on the piezoelectric film,
A communication device , wherein a heat radiating portion in contact with the substrate and the first electrode is provided at a central portion of the space .

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