Patent Publication Number: US-2015084710-A1

Title: Resonating element, resonator, electronic device, electronic apparatus, and moving body

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation patent application of U.S. application Ser. No. 13/915,740 filed Jun. 12, 2013, which claims priority to Japanese Patent Application No. 2012-133533 filed Jun. 13, 2012, all of which are incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a resonating element, a resonator, an electronic device, an electronic apparatus, and a moving body. 
     2. Related Art 
     In the related art, a surface mounting type electronic device has been widely used in which a piezoelectric resonator element where an excitation electrode is formed on a piezoelectric substrate is air-tightly sealed in a package. Here, the piezoelectric resonator element uses an AT cut quartz crystal resonator element or the like which performs thickness-shear vibration and employs, for example, a thin plate into which a piezoelectric substrate is cut at a cut angle called an AT cut, by using the characteristics in which the thin plate into which the piezoelectric substrate such as a quartz crystal is cut at a predetermined angle and thickness has an inherent resonance frequency. 
     For example, a surface mounting type quartz crystal oscillator, in which a quartz crystal resonator element and electronic parts such as semiconductor circuit elements including an oscillation circuit which oscillates the quartz crystal resonator element are mounted in the same package and are sealed, is used as an electronic device provided with the quartz crystal resonator element, and is widely used as a reference source of a frequency or time. 
     JP-A-2010-50508 discloses a quartz crystal oscillator in which a quartz crystal resonator is mounted on a pedestal formed by a quartz crystal which is disposed on an electronic part and an IC so as to substantially cover an opening of a recess of a container, in order to solve the problem that stable frequency-temperature characteristics cannot be obtained since stress distortion occurs due to a difference between linear expansion coefficients of a package material and the quartz crystal, resulting from an ambient temperature variation if a quartz crystal resonator element is directly mounted on a package using a conductive adhesive or the like. 
       FIG. 7  is a circuit diagram illustrating an example of a voltage controlled quartz crystal oscillator in the related art. The reference sign X1 indicates a quartz crystal resonator, the reference sign A1 indicates an amplifier, the reference signs Ca and Cb indicate capacitors, the reference sign D1 indicates a variable capacitance diode, the reference sign IN indicates a control voltage input terminal, the reference sign Rd indicates a resistor for applying a control voltage, and the reference sign OUT indicates a frequency output terminal of a voltage controlled quartz crystal oscillator. 
     In addition, a general equivalent circuit of the quartz crystal resonator X1 is shown in  FIG. 8 . In  FIG. 8 , the reference sign L1 indicates an equivalent series inductance, the reference sign C1 indicates an equivalent series capacitance, the reference sign R1 indicates an equivalent series resistance, and the reference sign C0 indicates a parallel capacitance. 
     If a load capacitance (combined capacitance) of a circuit side including the amplifier A1, viewed from the quartz crystal resonator X1 is set to CL, and a capacitance ratio is set to γ(C0/C1), a variation Δf/f0 of the resonance frequency f0 depending on the load capacitance CL is represented by the following well-known equation. 
       Δ f/f 0 =C 0/(2γ( C 0+ CL ))
 
     In other words, in relation to a frequency of the voltage controlled quartz crystal oscillator, the resonance frequency thereof varies depending on a variation in the load capacitance of an oscillation loop. 
     In addition, the variable capacitance diode D1 is a diode of which a capacitance value varies depending on a reverse voltage applied between two terminals thereof. Therefore, the variable capacitance diode D1 is inserted into the oscillation loop and a voltage applied thereto is varied, thereby controlling an oscillation frequency. 
     However, if the quartz crystal resonator is to be miniaturized so as to correspond to miniaturization of a recent portable telephone, an information terminal or the like, an excitation electrode of a quartz crystal resonator element is reduced. Therefore, a capacitance of a package for the equivalent series capacitance C1 or a ratio of floating capacitances between electrodes increases, and, as a result, there is a problem in that the capacitance ratio γ of the quartz crystal resonator increases, and thereby a desired frequency variable width cannot be obtained. 
     As a piezoelectric resonator capable of adjusting the frequency variable width, a piezoelectric resonator in which an inductor circuit pattern is provided in a package and an inductor L is connected to a piezoelectric resonator element accommodated in the package is disclosed in, for example, JP-A-2-226905. The inductor L which is inserted into the oscillation loop for this purpose is generally called an extension coil (or, simply a “coil”). This is based on a principle that, when the inductor L is connected in series to the piezoelectric resonator X1, a resonance frequency becomes lower than a frequency before the inductor L is inserted, but an antiresonance frequency does not vary, and thus an interval between the resonance frequency and the antiresonance frequency becomes spread. 
     However, in the piezoelectric resonator disclosed in JP-A-2-226905, a dedicated package in which the inductor circuit pattern is provided is necessary, and thus there is a problem in that a package does not have versatility. 
     SUMMARY 
     An advantage of some aspects of the invention is to solve at least a part of the problems described above and the invention can be implemented as the following forms or application examples. 
     Application Example 1 
     This application example is directed to a resonating element including a resonator element that includes a vibrating portion and an excitation electrode provided on both main surfaces of the vibrating portion; an intermediate substrate in which the resonator element is mounted so as to be spaced from the excitation electrode; and a spiral electrode pattern that is provided on the intermediate substrate, in which the electrode pattern is electrically connected to the excitation electrode. 
     According to this application example, when the resonating element has a structure in which the resonator element which is stably excited is mounted on the intermediate substrate, and is thus mounted in a package, the intermediate substrate reduces stress distortion due to a difference from a linear expansion coefficient of the package so as to obtain stable frequency-temperature characteristics. In addition, there is an effect of obtaining a desired frequency variable width in a case of forming an oscillator since an inductance is given by the spiral electrode pattern formed on the intermediate substrate even if a capacitance ratio  7  increases according to miniaturization. 
     Application Example 2 
     This application example is directed to the resonating element according to the application example described above, wherein the electrode pattern and the excitation electrode are connected in series or in parallel to each other. 
     According to this application example, the series connection corresponds to inserting an inductor into an oscillation loop of the oscillator, and thereby there is an effect of increasing a frequency variable width. In addition, the parallel connection achieves an effect that it is possible to suppress influence of an unnecessary capacitance such as a floating capacitance between electrodes in the oscillator. 
     Application Example 3 
     This application example is directed to the resonating element according to the application example described above, wherein the electrode pattern and the excitation electrode are disposed so as not to overlap each other in plan view. 
     According to this application example, the excitation electrode and the electrode pattern for inductance do not overlap each other, and thereby it is possible to prevent adverse effects caused by a floating capacitance between electrodes of the excitation electrode and the electrode pattern for inductance from being exerted on oscillation characteristics. 
     Application Example 4 
     This application example is directed to the resonating element according to the application example described above, wherein the electrode patterns are provided on both main surfaces of the intermediate substrate, and the electrode patterns are connected in series to each other. 
     According to this application example, it is possible to make an inductance large and to thereby increase more effectively a frequency variable width since the length of the electrode patterns can increase without increasing the size of the intermediate substrate as compared with a case where an electrode pattern for inductance is provided only one main surface of the intermediate substrate. 
     Application Example 5 
     This application example is directed to the resonating element according to the application example described above, wherein the electrode pattern is provided on one main surface of both main surfaces of the intermediate substrate which are front and rear surfaces, a shield electrode is provided on the other main surface, and the other main surface is opposite to the excitation electrode. 
     According to this application example, the shield electrode is provided between the excitation electrode and the electrode pattern for inductance, and thereby it is possible to prevent adverse effects caused by a floating capacitance between electrodes of the excitation electrode and the electrode pattern for inductance from being exerted on oscillation characteristics. 
     Application Example 6 
     This application example is directed to the resonating element according to the application example described above, wherein the resonator element includes the vibrating portion; and an outer edge portion that is integrally formed with an outer edge of the vibrating portion and is thinner than the vibrating portion. 
     According to this application example, since the vibrating portion of the resonator element has a mesa structure, coupling with a spurious profile can be prevented, and thus vibration energy of only the main vibration can be confined. Therefore, it is possible to provide a resonating element in which CI is small and a spurious frequency around a resonance frequency is suppressed. 
     Application Example 7 
     This application example is directed to the resonating element according to the application example described above, wherein the resonator element includes the vibrating portion; and an outer edge portion that is integrally formed with an outer edge of the vibrating portion and is thicker than the vibrating portion. 
     According to this application example, since even a high frequency resonating element in which the vibrating portion of the resonator element is very thin can be mounted on the thick part which is integrally formed with the vibrating portion, it is possible to provide a resonating element with good resistance to impact or resistance to vibration. 
     Application Example 8 
     This application example is directed to a resonator including the resonating element according to the application example described above; and a package in which the resonating element is mounted by including the intermediate substrate mounted therein. 
     According to this application example, the resonating element is accommodated in the package, and thereby it is possible to prevent influence of disturbance such as a temperature variation, a humidity variation or influence due to contamination. Therefore, there is an effect that it is possible to provide a resonator which has good frequency reproducibility, frequency-temperature characteristics, CI-temperature characteristics, and frequency aging characteristics and has thus a large frequency variable width. 
     Application Example 9 
     This application example is directed to an electronic device including the resonating element according to the application example described above; a package in which the resonating element is mounted by including the intermediate substrate mounted therein; and an oscillation circuit that excites the vibrating portion. 
     According to this application example, since the resonating element having an inductance is used, there is an effect that it is possible to provide an electronic device such as a voltage controlled oscillator having good frequency-temperature characteristics and a large frequency variable width. 
     Application Example 10 
     This application example is directed to an electronic device including the resonating element according to the application example described above; a package in which the resonating element is mounted by including the intermediate substrate mounted therein; and an oscillation circuit that excites the vibrating portion, in which the shield electrode is connected to a ground terminal of the package. 
     According to this application example, when the quartz crystal resonating element which has the shield electrode between the excitation electrode and the electrode pattern for inductance is mounted in a package, the shield electrode of the quartz crystal resonating element is connected to a ground terminal of the oscillator, and thereby there is an effect that it is possible to prevent adverse effects caused by a floating capacitance between electrodes of the excitation electrode and the electrode pattern for inductance from being exerted on oscillation characteristics. 
     Application Example 11 
     This application example is directed to an electronic apparatus including the resonating element according to the application example described above. 
     According to this application example, there is an effect that an electronic apparatus having a favorable reference frequency source can be formed using the resonating element with good frequency-temperature characteristics. 
     Application Example 12 
     This application example is directed to a moving body including the resonating element according to the application example described above. 
     According to this application example, there is an effect that a stable reference frequency source can be formed, and thus a moving body including a stable and accurate electronic control unit can be formed, using the resonating element with good frequency-temperature characteristics. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIGS. 1A and 1B  are schematic diagrams illustrating a structure of a resonator element according to a first embodiment of the invention, in which  FIG. 1A  is a plan view when viewed from the top, and  FIG. 1B  is a cross-sectional view taken along the line A-A. 
         FIGS. 2A to 2C  are schematic diagrams illustrating a structure of an intermediate substrate according to the first embodiment of the invention, in which  FIG. 2A  is a plan view when viewed from the top,  FIG. 2B  is a cross-sectional view taken along the line B-B, and  FIG. 2C  is a plan view when viewed from the bottom. 
         FIGS. 3A and 3B  are schematic diagrams illustrating a structure of a resonating element according to the first embodiment of the invention, in which  FIG. 3A  is a plan view when viewed from the top, and  FIG. 3B  is a cross-sectional view taken along the line C-C. 
         FIGS. 4A and 4B  are schematic diagrams illustrating a structure of a resonator according to the first embodiment of the invention, in which  FIG. 4A  is a plan view when viewed from the top, and  FIG. 4B  is a cross-sectional view taken along the line N-N. 
         FIGS. 5A and 5B  are schematic diagrams illustrating a structure of an electronic device according to the first embodiment of the invention, in which  FIG. 5A  is a plan view when viewed from the top, and  FIG. 5B  is a cross-sectional view taken along the line D-D. 
         FIG. 6  is a circuit diagram illustrating an example of a circuit of an oscillator. 
         FIG. 7  is a circuit diagram illustrating an example of a voltage controlled quartz crystal oscillation circuit as an oscillator in the related art. 
         FIG. 8  is a circuit diagram illustrating an example of an equivalent circuit of a quartz crystal resonator. 
         FIGS. 9A to 9C  are schematic diagrams illustrating a structure of an intermediate substrate according to a second embodiment of the invention, in which  FIG. 9A  is a plan view when viewed from the top,  FIG. 9B  is a cross-sectional view taken along the line E-E, and  FIG. 9C  is a plan view when viewed from the bottom. 
         FIGS. 10A and 10B  are schematic diagrams illustrating a structure of a resonating element according to the second embodiment of the invention, in which  FIG. 10A  is a plan view when viewed from the top, and  FIG. 10B  is a cross-sectional view taken along the line F-F. 
         FIGS. 11A to 11C  are schematic diagrams illustrating a structure of an intermediate substrate according to a third embodiment of the invention, in which  FIG. 11A  is a plan view when viewed from the top,  FIG. 11B  is a cross-sectional view taken along the line G-G, and  FIG. 11C  is a plan view when viewed from the bottom. 
         FIGS. 12A and 12B  are schematic diagrams illustrating a structure of a resonating element according to the third embodiment of the invention, in which  FIG. 12A  is a plan view when viewed from the top, and  FIG. 12B  is a cross-sectional view taken along the line H-H. 
         FIGS. 13A to 13C  are schematic diagrams illustrating a structure of an intermediate substrate according to a fourth embodiment of the invention, in which  FIG. 13A  is a plan view when viewed from the top,  FIG. 13B  is a cross-sectional view taken along the line I-I, and  FIG. 13C  is a plan view when viewed from the bottom. 
         FIGS. 14A and 14B  are schematic diagrams illustrating a structure of a resonating element according to the fourth embodiment of the invention, in which  FIG. 14A  is a plan view when viewed from the top, and  FIG. 14B  is a cross-sectional view taken along the line J-J. 
         FIGS. 15A and 15B  are schematic diagrams illustrating a structure of an electronic device according to the fourth embodiment of the invention, in which  FIG. 15A  is a plan view when viewed from the top, and  FIG. 15B  is a cross-sectional view taken along the line K-K. 
         FIGS. 16A and 16B  are schematic diagrams illustrating a structure of a resonator element according to a fifth embodiment of the invention, in which  FIG. 16A  is a plan view when viewed from the top, and  FIG. 16B  is a cross-sectional view taken along the line L-L. 
         FIGS. 17A and 17B  are schematic diagrams illustrating a structure of a resonating element according to the fifth embodiment of the invention, in which  FIG. 17A  is a plan view when viewed from the top, and  FIG. 17B  is a cross-sectional view taken along the line M-M. 
         FIGS. 18A and 18B  are schematic diagrams illustrating a structure of a resonator element according to a sixth embodiment of the invention, in which  FIG. 18A  is a plan view when viewed from the top, and  FIG. 18B  is a cross-sectional view taken along the line O-O. 
         FIGS. 19A and 19B  are schematic diagrams illustrating a structure of a resonating element according to the sixth embodiment of the invention, in which  FIG. 19A  is a plan view when viewed from the top, and  FIG. 19B  is a cross-sectional view taken along the line P-P. 
         FIG. 20  is a perspective view illustrating a configuration of a mobile type (or a notebook type) personal computer which is an electronic apparatus including the resonating element according to the first embodiment of the invention. 
         FIG. 21  is a perspective view illustrating a configuration of a mobile phone (including PHS) which is an electronic apparatus including the resonating element according to the first embodiment of the invention. 
         FIG. 22  is a perspective view illustrating a configuration of a digital camera which is an electronic apparatus including the resonating element according to the first embodiment of the invention. 
         FIG. 23  is a perspective view illustrating a configuration of an automobile which is a moving body to which the resonator or the electronic device including the resonating element according to the first embodiment of the invention is applied. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, embodiments of the invention will be described in detail with reference to the drawings. 
     Resonator Element 
       FIG. 1A  is a schematic plan view when an example of a quartz crystal resonator element which is a resonator element according to a first embodiment of the invention is viewed from the top, and  FIG. 1B  is a cross-sectional view taken along the line A-A of  FIG. 1A . 
     A quartz crystal resonator element  1  which is formed using a quartz crystal is formed using, for example, a quartz crystal wafer which is a single-crystalline substrate which is cut at a predetermined cut angle from a quartz crystal Lambert in which some of synthetic quartz crystal ore is formed on a block by clarifying a crystal axis (optical axis) thereof. Here, the predetermined cut angle indicates a cut angle which is tilted by a desired angle with respect to the crystal axis of the quartz crystal, and, in the present embodiment, a description will be made of the quartz crystal resonator element  1  which is formed using a so-called AT cut quartz crystal cut at a cut angle tilted by 35° 15′ from the crystal axis and shows a thickness-shear vibration mode. The quartz crystal resonator element  1  using this AT cut quartz crystal is a piezoelectric resonator element with good temperature characteristics which can provide a stable frequency in a wide temperature region. 
     The quartz crystal resonator element  1  includes, as shown in  FIG. 1A , a quartz crystal substrate  10 , excitation electrodes  20   a  and  20   b , and external connection terminals  22   a  and  22   b . The quartz crystal substrate  10  includes a support portion  14  which is a fixed end (the left side of the quartz crystal resonator element  1  in  FIGS. 1A and 1B ) and a vibrating portion  12  which is a free end (one end (the right side of the quartz crystal resonator element  1  in  FIGS. 1A and 1B ) on a side of the quartz crystal resonator element  1  which is not fixed). The support portion  14  indicates a region between the vibrating portion  12  and the fixed end (the left side) of the quartz crystal resonator element  1 . A pair of excitation electrodes  20   a  and  20   b  are provided so as to be opposite to each other on both main surfaces of the vibrating portion  12 . In addition, the external connection terminals  22   a  and  22   b  which respectively correspond to the excitation electrodes  20   a  and  20   b  are provided on both main surfaces of the support portion  14 , and the excitation electrodes  20   a  and  20   b  are respectively electrically connected to the corresponding to external connection terminals  22   a  and  22   b  via lead electrodes  21   a  and  21   b . In addition, the external connection terminals  22   a  and  22   b  provided so as to be opposite to each other on both the main surfaces of the support portion  14  are respectively electrically connected to each other via side electrodes  23   a  and  23   b.    
     The quartz crystal substrate  10  is etched so as to form an exterior of the quartz crystal resonator element  1 , and, then, a metal film using, for example, gold (Au), is formed on a ground layer of, for example, nickel (Ni) or chrome (Cr) through deposition or sputtering and is subsequently patterned using photolithography, thereby forming the electrode pattern of the electrodes, the terminals, and the like. 
     In the embodiment shown in  FIG. 1A , an example in which shapes of the excitation electrodes  20   a  and  20   b  are rectangular has been described, but shapes of the excitation electrodes  20   a  and  20   b  are not limited thereto and may be circular or elliptical. 
     Intermediate Substrate 
       FIG. 2A  is a schematic plan view when an intermediate substrate according to the first embodiment of the invention is viewed from the top,  FIG. 2B  is a cross-sectional view taken along the line B-B of  FIG. 2B , and  FIG. 2C  is a schematic plan view when  FIG. 2A  is viewed from the bottom. 
     An intermediate substrate  2  includes, as shown in  FIGS. 2A to 2C , a substrate  15 , an electrode pattern  30  for inductance, terminals  32   a  and  32   b  for joining to the quartz crystal resonator element  1 , and connection terminals  34   a  and  34   b . The substrate  15  includes a base portion  17 , a joining region to the quartz crystal resonator element  1 , and an inductance forming region (a region in which the spiral electrode pattern  30  is formed) which are integrally formed in an arranged state on the plane. In addition, if the substrate  15  is formed of a quartz crystal substrate which is an insulating material and has the same cut angle as the quartz crystal resonator element  1 , there is no difference in the linear expansion coefficient, and thus stress distortion caused by joining to the quartz crystal resonator element  1  does not occur, thereby obtaining stable frequency-temperature characteristics. 
     The base portion  17  is a portion which is fixed when a quartz crystal resonating element  3  in which the quartz crystal resonator element  1  overlaps the intermediate substrate  2  is joined to a package (refer to  FIGS. 4A to 5B ), and is provided with the connection terminals  34   a  and  34   b  used for electrical connection between the quartz crystal resonator element  1 , the electrode pattern  30  for inductance, and the package. In addition, the connection terminals  34   a  and  34   b  which are provided so as to be opposite to each other on both main surfaces of the base portion  17  are respectively electrically connected to each other via side electrodes  35   a  and  35   b.    
     As shown in  FIG. 2A , one main surface of the substrate  15  is a surface on which the quartz crystal resonator element  1  is mounted, and is provided with the joining terminals  32   a  and  32   b  and the electrode pattern  30  for inductance. The connection terminal  34   a  is electrically connected to the terminal  32   a  for joining to the quartz crystal resonator element  1  via a lead electrode  33 . In addition, the terminal  32   b  for joining to the quartz crystal resonator element  1  is electrically connected to the electrode pattern  30  for inductance via a lead electrode  31 . The electrode pattern  30  for inductance is an inductor which is inserted into an oscillation loop of an oscillation circuit such as a quartz crystal oscillator and is generally called an extension coil or simply a coil. The electrode pattern  30  for inductance of the present embodiment is formed as a coil in which a thin and long wire is directed to the inner circumference from the outer circumference so as to have a rectangular spiral shape in the induction forming region on one main surface of the substrate  15 . In addition, a shape of the electrode pattern  30  for inductance is not limited thereto, and may be a shape in which a distance from a start end to a finish end of an inductance pattern using a wire is as long as possible, for example, a typical spiral shape with an arc. Further, the electrode pattern  30  for inductance may be formed as a coil with a shape which is folded many times from one end part to the other part. 
     In addition, as shown in  FIG. 2C , the other main surface of the substrate  15  is a surface on a side which is joined to a package in the quartz crystal resonator or the quartz crystal oscillator of the present embodiment (refer to  FIGS. 4A to 5B ). A lead electrode  36  is drawn out from the connection terminal  34   b  toward the inductance forming region, is led up to directly under the central end part of the electrode pattern  30  for inductance provided on one main surface, and is electrically connected to the electrode pattern  30  for inductance via an in-layer pattern  37  such as a through-hole. Thereby, a single inductor is formed by the electrode pattern  30  for inductance between the terminal  32   b  for joining to the quartz crystal resonator element  1  provided on one main surface in the base portion  17  of the substrate  15  and the connection terminal  34   b  provided in the base portion  17 . In addition, in the present embodiment, in order to increase a frequency variable width of the oscillator, the quartz crystal resonator element  1  is connected in series to the electrode pattern  30  for inductance, the invention is not limited thereto, and the quartz crystal resonator element  1  may be connected in parallel to the electrode pattern  30  for inductance in order to suppress an unnecessary capacitance such as a floating capacitance between the respective electrodes in the oscillator. 
     Resonating Element 
     Next, a description will be made of a resonating element in which the quartz crystal resonator element  1  and the intermediate substrate  2  according to the present embodiment are stacked and are joined to each other with reference to the drawings. 
       FIG. 3A  is a schematic plan view when an example of a quartz crystal resonating element which is a resonating element according to the first embodiment of the invention is viewed from the top, and  FIG. 3B  is a cross-sectional view taken along the line C-C of  FIG. 3A . 
     As shown in  FIGS. 3A and 3B , the quartz crystal resonating element  3  is formed by mounting the quartz crystal resonator element  1  on the intermediate substrate  2 . The terminals  32   a  and  32   b  for joining to the quartz crystal resonator element  1  provided on one main surface of the intermediate substrate  2  are aligned with the corresponding external connection terminals  22   a  and  22   b  and are joined thereto via a joining member  40 . The joining member  40  uses a conductive joining member  40  such as a conductive adhesive or solder, and thereby mechanical joining can be performed along with electrical connection. In addition, the vibrating portion  12  of the quartz crystal resonator element  1  is disposed with a gap by the joining member  40  with respect to one main surface of the intermediate substrate  2  on which the electrode pattern  30  for inductance is formed. 
     In addition, if the substrate  15  of the intermediate substrate  2  is formed of a quartz crystal substrate having the same cut angle as the quartz crystal resonator element  1 , there is no difference in the linear expansion coefficient, and stress distortion occurring when the quartz crystal resonator element  1  and the intermediate substrate  2  are stacked and are joined is small. Therefore, there is an effect that a resonating element having stable frequency-temperature characteristics can be obtained. 
     Resonator 
       FIG. 4A  is a schematic plan view when an example of a quartz crystal resonator which is a resonator according to the first embodiment of the invention is viewed from the top, and  FIG. 4B  is a cross-sectional view taken along the line N-N of  FIG. 4A . In addition, in  FIGS. 4A and 4B , for convenience of description of an inner configuration of the quartz crystal resonator, a state in which a lid member is removed is shown. 
     A quartz crystal resonator  4  includes the quartz crystal resonating element  3 , a package main body  60  which is formed in a rectangular box shape so as to accommodate the quartz crystal resonating element  3 , and a lid member  70  made of metal, ceramic, glass, or the like. 
     The package main body  60 , as shown in  FIG. 4B , is formed by stacking a first substrate  61 , a second substrate  62 , a sealing  68 , and a mounting terminal  86 . The mounting terminal  86  is formed in plurality on an outer bottom of the first substrate  61 . The second substrate  62  is a ring-shaped body of which the center is removed, and the sealing  68  such as, for example, Kovar is formed on the upper rim of the second substrate  62 . 
     A cavity  65  which accommodates the quartz crystal resonating element  3  is formed by the second substrate  62 . A plurality of element mounting pads  81  which are electrically connected to the mounting terminals  86  by conductors (not shown) formed inside the first substrate  61  are provided at predetermined positions of the upper surface of the first substrate  61 . The element mounting pads  81  are disposed so as to correspond to the connection terminals  34   a  and  34   b  formed in the base portion  17  of the intermediate substrate  2  when the quartz crystal resonating element  3  is placed. 
     The above-described first substrate  61  and second substrate  62  of the package main body  60  are made of a ceramic insulating material or the like. In addition, the respective electrodes, terminals, wire patterns or in-layer wire patterns electrically connecting the electrodes or the terminals to each other, or the like provided in the package main body  60  are generally formed by screen-printing a metal wire material such as tungsten (W) or molybdenum (Mo) on a ceramic insulating material so as to be baked at high temperature, and by performing plating such as nickel (Ni) or gold (Au) thereon. 
     If the quartz crystal resonating element  3  is to be supported and fixed (mounted), first, a joining member  42  and a joining member  44 , for example, conductive adhesives are coated at positions corresponding to the element mounting pads  81  which correspond to the connection terminals  34   a  and  34   b  of the quartz crystal resonating element  3  and the end part (the right side of the quartz crystal resonating element  3  in  FIGS. 4A and 4B ) on the opposite side to the base portion  17  of the intermediate substrate  2  forming the quartz crystal resonating element  3 , and a load is applied thereto by placing the connection terminals  34   a  and  34   b  of the quartz crystal resonating element  3  and the end part of the intermediate substrate  2  of the quartz crystal resonating element  3  thereon. 
     Next, the joining member  42  and the joining member  44  are put inside a high temperature furnace of a predetermined temperature for a predetermined time so as to be cured. The joining member  42  and the joining member  44  are cured and then undergo an annealing process, and a frequency is adjusted by adding the mass to the excitation electrode  20   a  or by reducing the mass. Thereafter, the lid member  70  is placed on the sealing  68  formed on the upper surface of the second substrate  62  of the package main body  60 , and the lid member  70  is sealed through seam welding in vacuum or in a nitrogen gas atmosphere such that the quartz crystal resonator  4  is completed. Alternatively, there may be a method in which the lid member  70  is placed on low melting glass coated on the upper surface of the package main body  60  and is melted so as to be cohered. Also in this case, the cavity  65  of the package main body  60  is made to be vacuum, or is filled with an inert gas such as a nitrogen gas, thereby completing the quartz crystal resonator  4 . 
     In addition, in the present embodiment, an example of using a conductive adhesive as the joining member  44  has been described, but, in a case where electrical connection is not necessary, a non-conductive adhesive may be used. Further, the end part on the opposite side to the connection terminals  34   a  and  34   b  of the quartz crystal resonating element  3  is joined in order to increase the mounting strength of the quartz crystal resonating element  3 , but the invention is not limited thereto, and the end part may not be joined. 
     Electronic Device 
       FIG. 5A  is a schematic plan view when an example of a quartz crystal oscillator which is an electronic device according to the first embodiment of the invention is viewed from the top, and  FIG. 5B  is a cross-sectional view taken along the line D-D of  FIG. 5A . In addition, in  FIGS. 5A and 5B , for convenience of description of an inner configuration of the quartz crystal oscillator, a state in which the lid member is removed is shown. 
     A quartz crystal oscillator  5  includes a package main body  60   a , the lid member  70 , the quartz crystal resonating element  3 , and an IC chip  50  in which an oscillation circuit exciting the quartz crystal resonating element  3  is mounted. 
     The quartz crystal oscillator  5  according to the present embodiment is a one-chip quartz crystal oscillator of a so-called Surface Mount Device (SMD) type in which the IC chip  50  including the quartz crystal resonator element  1  and the oscillation circuit is joined to the inner cavity  65  of the package main body  60   a  and is sealed, and surface mounting is possible. In addition, the SMD type quartz crystal oscillator  5  which is standardized as a surface mount part is advantageous to simplification of mounting processes or low costs, since it is not necessary to cut or mold a lead wire for external connection so as to conform with a connection terminal shape of an external substrate, and automation for mounting on an external substrate is easily performed, for example, unlike a type of quartz crystal resonator in which a quartz crystal resonator element joined to a substrate is covered with a cylindrical cap so as to be sealed. 
     As shown in  FIG. 5B , the package main body  60   a  is formed by stacking a first substrate  61 , a second substrate  62 , a third substrate  63 , a sealing  68 , and a mounting terminal  86 . The mounting terminal  86  is formed in plurality on the outer bottom of the first substrate  61 . The second substrate  62  and the third substrate  63  are ring-shaped bodies of which the center is removed, and the sealing  68  such as Kovar is formed on the upper rim of the second substrate  62 . 
     A cavity  65  which accommodates the quartz crystal resonating element  3  and a recess  66  which accommodates the IC chip  50  in which the oscillation circuit exciting the quartz crystal resonating element  3  is mounted are formed by the second substrate  62  and the third substrate  63 . The upper surface of the first substrate  61  which is a bottom of the recess  66  is provided with a plurality of IC joining terminals  84  to which the IC chip  50  is connected. A plurality of element mounting pads  81  which are electrically connected to the mounting terminals  86  by conductors (not shown) formed inside the first substrate  61  and the third substrate  63  are provided at predetermined positions of the upper surface of the third substrate  63 . The element mounting pads  81  are disposed so as to correspond to the connection terminals  34   a  and  34   b  formed in the base portion  17  of the intermediate substrate  2  when the quartz crystal resonating element  3  is placed. 
     The above-described first substrate  61  to the third substrate  63  of the package main body  60   a  are made of a ceramic insulating material or the like. In addition, the respective electrodes, terminals, wire patterns or in-layer patterns electrically connecting the electrodes or the terminals to each other, or the like, provided in the package main body  60   a  are generally formed by screen-printing a metal wire material such as tungsten (W) or molybdenum (Mo) on a ceramic insulating material so as to be baked at high temperature, and by performing plating such as nickel (Ni) or gold (Au) thereon. 
     In  FIG. 5B , the IC chip  50  which is a semiconductor circuit element including an excitation circuit for exciting and resonating the quartz crystal resonator element  1  is joined to the IC joining terminals  84  provided at the bottom of the recess  66  of the package main body  60   a , for example, using a brazing filler metal or an adhesive. In the present embodiment, the IC chip  50  is joined onto the IC joining terminals  84  in a face-down manner by bumps  46  which are made of a metal or a solder provided in electrode pad (not shown) of the IC chip  50  in advance. The joining of the IC chip  50  through the face-down joining is advantageous to thinning (low height) of the quartz crystal oscillator  5 . In addition, after the IC chip  50  is joined in a face-down manner by the bumps  46 , a gap between the IC chip  50  and the bottom of the recess  66  of the package main body  60   a  is filled with an under-filling material which is cured, so as to further increase the joining strength of the IC chip  50 . Further, joining of the IC chip  50  to the package main body  60   a  is not limited to the face-down joining, and may be performed using other IC mounting techniques such as wire bonding. 
     The quartz crystal resonating element  3  in which the quartz crystal resonator element  1  is joined onto the intermediate substrate  2  is joined using conductive joining member  42  and joining member  44  such as conductive adhesives in the cavity  65  of the package main body  60   a  in a state in which the connection terminals  34   a  and  34   b  of the intermediate substrate  2  are aligned with the corresponding element mounting pads  81 . In addition, positions or the number of the element mounting pads  81  are not limited to the aspect shown in  FIGS. 5A and 5B , and may be appropriately varied depending on a connection relationship between the quartz crystal resonator element  1  and the electrode pattern  30  for inductance, and a connection relationship between the quartz crystal resonating element  3  and the IC chip  50 . Further, a connection between the quartz crystal resonating element  3  and the element mounting pads  81  is also not limited to the face-down joining, and may be a connection using wire bonding, or may be a connection using a combination of the face-down joining and the wire bonding. Furthermore, direct wire bonding may be performed between the terminals  32   a  and  32   b  for joining to the quartz crystal resonator element  1  and the element mounting pads  81 . 
     Thereby, the IC chip  50  including oscillation circuit oscillating the quartz crystal resonator element  1  can be connected in series to the quartz crystal resonator element  1  via the electrode pattern  30  for inductance of the intermediate substrate  2  interposed therebetween.  FIG. 6  is a circuit diagram illustrating an example of a circuit in which the electrode pattern  30  for inductance is interposed between the quartz crystal resonator element  1  and the IC chip  50  in the quartz crystal oscillator. As shown in  FIG. 6 , in the quartz crystal oscillator, the IC chip  50  includes terminals  50   a  and  50   b , and, in the series circuit of the quartz crystal resonator element  1  and the electrode pattern  30  for inductance between the two terminals, the quartz crystal resonator element  1  may be connected to the terminal  50   a  and the electrode pattern  30  for inductance may be connected to the terminal  50   b.    
     In addition, the quartz crystal resonator element  1  is disposed in the package main body  60   a  with the intermediate substrate  2  including the electrode pattern  30  for inductance interposed between the quartz crystal resonator element  1  and the IC chip  50 . 
     In addition, of the joining member  42  and the joining member  44  used for joining between the quartz crystal resonating element  3  and the package main body  60   a , the conductive joining member  42  may use a conductive adhesive or the like in which, for example, polyimide, or a resin such as a silicon-based or epoxy-based resin is mixed with silver (Ag) filament or nickel (Ni) powder. 
     The lid member  70  is joined onto the second substrate  62  of the package main body  60   a  in which the IC chip  50  and the quartz crystal resonating element  3  are joined together. Specifically, the lid member  70  which is made of a metal such as 42Alloy (an alloy in which nickel of 42% is contained in iron) or Kovar (an alloy of iron, nickel, and cobalt) is seam-welded via the sealing  68  which is formed by cutting a iron-nickel (Fe—Ni) alloy or the like in a frame shape. In addition, the lid member  70  may use ceramic, glass, or the like in addition to the above-described metal, and, for example, in a case where the lid member  70  made of glass is used, a joining member may be appropriately selected depending on a material of the lid member  70  such as using low melting glass as a joining member, and thereby the package main body  60   a  may be joined to the lid member  70 . 
     The cavity  65  formed by the package main body  60   a  and the lid member  70  is a space for the quartz crystal resonator element  1  being operated. The cavity  65  may be sealed airtightly in a decompressed space or in an inert gas atmosphere in the quartz crystal oscillator  5  according to the present embodiment. For example, in a case where the cavity  65  is sealed airtightly in a compressed space, the quartz crystal oscillator  5  is placed in a vacuum chamber in a state in which a solid sealing material is disposed in a sealing hole (not shown) of the package main body  60   a , and is decompressed up to a predetermined degree of vacuum so as to exhaust a gas emitted from inside of the quartz crystal oscillator  5  through the sealing hole, and then the solid sealing material is melted and is cured so as to close the sealing hole, thereby sealing the cavity  65 . Thereby, the quartz crystal resonator element  1  and the IC chip  50  joined in the recess  66  of the package main body  60   a  can be airtightly sealed. 
     In addition, the sealing material preferably has, as a melting point, a temperature higher than a reflow temperature when the completed quartz crystal oscillator  5  is mounted on an external mounting substrate, and may use, for example, an alloy of gold and tin (Sn), an alloy of gold and germanium (Ge), or the like. 
     According to the quartz crystal oscillator  5  of the above-described embodiment, the IC chip  50  which is a semiconductor circuit element including the oscillation circuit and the electrode pattern  30  for inductance connected to the quartz crystal resonator element  1  which is a piezoelectric resonator element are provided inside the package main body  60   a , and thus it is possible to provide the quartz crystal oscillator  5  which is a one-chip piezoelectric oscillator having high reliability and a large frequency variable width due to the one-seal structure. 
     Particularly, in the quartz crystal oscillator  5  of the above-described embodiment, the electrode pattern  30  for inductance is connected in series to the quartz crystal resonator element  1 , and thus it is possible to more notably achieve an effect of increasing a frequency variable width by inserting an inductor into the oscillation loop of the quartz crystal oscillator  5 . 
     In addition, since the quartz crystal resonator element  1  is mounted on the intermediate substrate  2  in which the electrode pattern  30  for inductance is formed, it is possible to provide the one-chip quartz crystal oscillator  5  of which oscillation characteristics are stable by using a general purpose package. 
     Further, since the intermediate substrate  2  in which the electrode pattern  30  for inductance is disposed between the IC chip  50  and the quartz crystal resonator element  1 , the intermediate substrate  2  achieves a shield effect, and thus it is possible to suppress influence caused by a floating capacitance between the electrodes of the IC chip  50  and the quartz crystal resonator element  1  from being exerted on oscillation characteristics. 
     Modification Example 1 of Intermediate Substrate 
       FIGS. 9A to 9C  show a modification example of the intermediate substrate shown in  FIGS. 2A to 2C , in which  FIG. 9A  is a schematic plan view when a structure of the intermediate substrate according to a second embodiment of the invention is viewed from the top,  FIG. 9B  is a cross-sectional view taken along the line E-E of  FIG. 9A , and  FIG. 9C  is a schematic plan view when  FIG. 9A  is viewed from the bottom. 
     An intermediate substrate  102  according to the present modification example includes, as shown in  FIGS. 9A to 9C , a substrate  115 , an electrode pattern  130  for inductance, terminals  132   a  and  132   b  for joining to the quartz crystal resonator element  1 , and connection terminals  134   a  and  134   b , and has the same configuration as the intermediate substrate  2  of the embodiment shown in  FIGS. 2A to 2C . However, a gap between the electrode pattern  130  for inductance and the terminals  132   a  and  132   b  for joining to the quartz crystal resonator element  1  is substantially the same length as the length of the quartz crystal resonator element  1 . 
     One main surface of the substrate  115  is a surface on which the quartz crystal resonator element  1  is mounted, and is provided with the electrode pattern  130  for inductance, the joining terminals  132   a  and  132   b , and the connection terminals  134   a  and  134   b , which are respectively electrically connected to each other via lead electrodes  131  and  133 . In addition, the other main surface of the substrate  115  is provided with the connection terminals  134   a  and  134   b , and a lead electrode  136  is drawn out from the connection terminal  134   b  and is electrically connected to the electrode pattern  30  for inductance provided on one main surface via an in-layer wire  37  using a through-hole. 
     Since, in the intermediate substrate  102 , a gap between the electrode pattern  130  for inductance and the terminals  132   a  and  132   b  for joining to the quartz crystal resonator element  1  is wide, in a case where a quartz crystal resonating element is formed by stacking and joining the quartz crystal resonator element  1  and the intermediate substrate  102 , the excitation electrode  20   b  of the quartz crystal resonator element  1  and the electrode pattern  130  for inductance can be made not to overlap each other. 
     Modification Example 1 of Quartz Crystal Resonating Element 
       FIGS. 10A and 10B  show a modification example of the quartz crystal resonating element, in which  FIG. 10A  is a schematic plan view when a structure of the quartz crystal resonating element according to the second embodiment of the invention is viewed from the top, and  FIG. 10B  is a cross-sectional view taken along the line F-F of  FIG. 10A . 
     As shown in  FIGS. 10A and 10B , a quartz crystal resonating element  103  according to the present modification example is formed by mounting the quartz crystal resonator element  1  on the intermediate substrate  102  which is a modification example of the intermediate substrate  2  of the embodiment shown in  FIGS. 2A to 2C . The terminals  132   a  and  132   b  for joining to the quartz crystal resonator element  1  provided on one main surface of the intermediate substrate  102  are aligned with the corresponding external connection terminals  22   a  and  22   b  of the quartz crystal resonator element  1  and are joined thereto via a joining member  40 . In addition, the vibrating portion  12  of the quartz crystal resonator element  1  is disposed with a gap by the joining member  40  with respect to one main surface of the intermediate substrate  102  on which the electrode pattern  130  for inductance is formed. 
     In the quartz crystal resonating element  103 , a gap between the electrode pattern  130  for inductance and the terminals  132   a  and  132   b  for joining to the quartz crystal resonator element  1  provided on one main surface of the intermediate substrate  102  is wide. For this reason, in a case where the quartz crystal resonator element  1  is joined onto the intermediate substrate  102 , the excitation electrode  20   b  of the quartz crystal resonator element  1  and the electrode pattern  130  for inductance do not overlap, and thus it is possible to prevent a floating capacitance between electrodes of the excitation electrode  20   b  and the electrode pattern  130  for inductance. 
     Modification Example 2 of Intermediate Substrate 
       FIGS. 11A to 11C  show a modification example of the intermediate substrate, in which  FIG. 11A  is a schematic plan view when a structure of the intermediate substrate according to a third embodiment of the invention is viewed from the top,  FIG. 11B  is a cross-sectional view taken along the line G-G of  FIG. 11A , and  FIG. 11C  is a schematic plan view when  FIG. 11A  is viewed from the bottom. 
     As shown in  FIG. 11A , in an intermediate substrate  202  according to the present modification example, a configuration of one main surface side of the substrate  215  is completely the same as the configuration of the intermediate substrate  2  of the embodiment shown in  FIGS. 2A to 2C . In other words, the substrate  215  is provided with an electrode pattern  230   a  for inductance, terminals  232   a  and  232   b  for joining to the quartz crystal resonator element  1 , and connection terminals  234   a  and  234   b.    
     In addition, as shown in  FIG. 11C , on the other main surface of the substrate  215 , a lead electrode  233   b  is drawn out from the connection terminal  234   b  and is connected to an electrode pattern  230   b  for inductance which is formed in an inductance forming region. 
     The electrode pattern  230   b  for inductance formed on the other main surface is formed in the same shape and arrangement so as to overlap the electrode pattern  230   a  for inductance formed on one main surface in plan view. In this way, it is possible to suppress a defect such as reduction in frequency variable sensitivity due to canceling-out of inductances between the electrode patterns for inductance in a case where shapes or arrangements of the electrode patterns  230   a  and  230   b  for inductance on both main surfaces are misaligned, for example, in a case where winding directions of the rectangular spiral shapes are opposite to each other. 
     The electrode pattern  230   a  for inductance and the electrode pattern  230   b  for inductance formed on both main surfaces of the intermediate substrate  202  are electrically connected to each other at the center of the inductance forming region via an in-layer wire  237  such as a through-hole. Thereby, it is possible to provide the intermediate substrate  202  in which the two electrode patterns  230   a  and  230   b  for inductance are connected in series to each other between the terminal  232   b  for joining to the quartz crystal resonator element  1  provided on one main surface and the connection terminal  234   b  provided on the other main surface. 
     According to the intermediate substrate  202  of the present modification example, two electrode patterns  230   a  and  230   b  for inductance are connected in series to each other formed on both main surfaces of the intermediate substrate  202  are formed in a state of being connected in series to each other. Thereby, it is possible to increase an effect of increasing a frequency variable width by the electrode patterns  230   a  and  230   b  for inductance without increasing the size of the intermediate substrate as compared with a case where an electrode pattern for inductance is provided only one main surface of the intermediate substrate. 
     Modification Example 2 of Quartz Crystal Resonating Element 
       FIGS. 12A and 12B  show a modification example of the quartz crystal resonating element, in which  FIG. 12A  is a schematic plan view when a structure of the quartz crystal resonating element according to a third embodiment of the invention is viewed from the top, and  FIG. 12B  is a cross-sectional view taken along the line H-H of  FIG. 12A . 
     As shown in  FIGS. 12A and 12B , a quartz crystal resonating element  203  according to the present modification example is formed by mounting the quartz crystal resonator element  1  on the intermediate substrate  202  which is a modification example of the intermediate substrate  2  of the embodiment shown in  FIGS. 2A to 2C . The terminals  232   a  and  232   b  for joining to the quartz crystal resonator element  1  provided on one main surface of the intermediate substrate  202  are aligned with the corresponding external connection terminals  22   a  and  22   b  of the quartz crystal resonator element  1  and are joined thereto via a joining member  40 . In addition, the vibrating portion  12  of the quartz crystal resonator element  1  is disposed with a gap by the joining member  40  with respect to one main surface of the intermediate substrate  202  on which the electrode pattern  230   a  for inductance is formed. 
     Since, in the quartz crystal resonating element  203 , the electrode patterns  230   a  and  230   b  for inductance provided on both main surfaces of the intermediate substrate  202  are formed in a state of being connected in series to each other, it is possible to obtain a frequency variable width larger than in the quartz crystal resonating element  3  of the embodiment shown in  FIGS. 3A and 3B . 
     Modification Example 3 of Intermediate Substrate 
       FIGS. 13A to 13C  show a modification example of the intermediate substrate, in which  FIG. 13A  is a schematic plan view when a structure of the intermediate substrate according to a fourth embodiment of the invention is viewed from the top,  FIG. 13B  is a cross-sectional view taken along the line I-I of  FIG. 13A , and  FIG. 13C  is a schematic plan view when  FIG. 13A  is viewed from the bottom. 
     An intermediate substrate  302  according to the present modification example includes, as shown in  FIGS. 13A to 13C , a substrate  315 , a shield electrode  340 , terminals  332   a  and  332   b  for joining to the quartz crystal resonator element  1 , connection terminals  334   a  and  334   b , and an electrode pattern  330  for inductance. 
     One main surface of the substrate  315  is a surface on which the quartz crystal resonator element  1  is mounted, and is provided with the shield electrode  340 , a pad electrode  341 , the joining terminals  332   a  and  332   b , the connection terminals  334   a  and  334   b , and lead electrodes  333   a  and  333   b.    
     The other main surface of the substrate  315  is provided with an electrode pattern  330  for inductance, a pad electrode  343 , connection terminals  334   a  and  334   b , and lead electrodes  331   b  and  336 . The electrode pattern  330  for inductance and the connection terminal  334   b  are electrically connected to each other via the lead electrode  336 . In addition, an insulating film  55 , for example, a silicon oxide film is formed on the electrode pattern  330  for inductance so as to prevent the electrode pattern  330  for inductance and the lead electrode  336  from being short-circuited. 
     The connection terminals  334   a  and  334   b , the lead electrodes  331   b  and  333   b , and the pad electrodes  341  and  343 , formed on both main surfaces of the substrate  315 , are respectively electrically connected to each other via side electrodes  335   a ,  335   b ,  337   b  and  342 . 
     Since, in the intermediate substrate  302 , the shield electrode  340  is formed on the surface on which the quartz crystal resonator element  1  is mounted, in a case where a quartz crystal resonating element is formed by stacking and joining the quartz crystal resonator element  1  and the intermediate substrate  102 , it is possible to prevent influence of a floating capacitance between electrodes of the excitation electrode  20   b  of the quartz crystal resonator element  1  and the electrode pattern  330  for inductance by using the shield electrode  340 . 
     In addition, in the intermediate substrate  302  according to the present modification example, the joining terminals  332   a  and  332   b  are formed on the surface on which the shield electrode  340  is formed; however, the joining terminals  332   a  and  332   b  may be formed on the surface on which the electrode pattern  330  for inductance with a configuration of preventing a short circuit by using the insulating film  55  is formed. 
     In addition, in the same manner as the intermediate substrate  2  of the embodiment shown in  FIGS. 2A to 2C , the electrode pattern  330  for inductance with a configuration of preventing a short circuit by using the insulating film  55  and the joining terminals  332   a  and  332   b  may be formed on the same surface, and the shield electrode  340  may not be formed. 
     Modification Example 3 of Quartz Crystal Resonating Element 
       FIGS. 14A and 14B  show a modification example of the quartz crystal resonating element, in which  FIG. 14A  is a schematic plan view when a structure of the quartz crystal resonating element according to the fourth embodiment of the invention is viewed from the top, and  FIG. 14B  is a cross-sectional view taken along the line J-J of  FIG. 14A . 
     As shown in  FIGS. 14A and 14B , a quartz crystal resonating element  303  according to the present modification example is formed by mounting the quartz crystal resonator element  1  on the intermediate substrate  302  which is a modification example of the intermediate substrate  2  of the embodiment shown in  FIGS. 2A to 2C . The terminals  332   a  and  332   b  for joining to the quartz crystal resonator element  1  provided on one main surface of the intermediate substrate  302  are aligned with the corresponding external connection terminals  22   a  and  22   b  of the quartz crystal resonator element  1  and are joined thereto via a joining member  40 . In addition, the vibrating portion  12  of the quartz crystal resonator element  1  is disposed with a gap by the joining member  40  with respect to one main surface of the intermediate substrate  302  on which a shield electrode  340  is formed. 
     Since, in the quartz crystal resonating element  303 , the shield electrode  340  is formed on the surface of the intermediate substrate  302  on which the quartz crystal resonator element  1  is mounted, it is possible to prevent adverse effects caused by a floating capacitance between electrodes of the excitation electrode  20   b  of the quartz crystal resonator element  1  and the electrode pattern  330  for inductance from being exerted on oscillation characteristics. 
     Further, if an intermediate substrate (not shown) in which the joining terminals  332   a  and  332   b  are formed on a surface on which the electrode pattern  330  for inductance with a configuration of preventing a short circuit by using the insulating film  55  is formed is used in the quartz crystal resonating element  303  of the present modification example, the electrode pattern  330  for inductance is formed on the surface on which the quartz crystal resonator element  1  is mounted, and the shield electrode  340  is formed on the surface opposite to the IC chip  50 . Therefore, in a case of forming a quartz crystal oscillator, it is possible to prevent adverse effects caused by a floating capacitance between electrodes of the electrode pattern  330  for inductance and the IC chip  50  from being exerted on oscillation characteristics. 
     Further, if a quartz crystal resonating element is formed using an intermediate substrate (not shown) in which the electrode pattern  330  for inductance with a configuration of preventing a short circuit by using the insulating film  55  and the joining terminals  332   a  and  332   b  are formed on the same surface and the shield electrode  340  is not formed, and is used in a quartz crystal oscillator, it is possible to obtain characteristics equivalent to the quartz crystal oscillator  5  of the embodiment shown in  FIGS. 5A and 5B . 
     Modification Example 1 of Quartz Crystal Oscillator 
       FIGS. 15A and 15B  show a modification example of the quartz crystal oscillator, in which  FIG. 15A  is a schematic plan view when a structure of a quartz crystal oscillator according to the fourth embodiment of the invention is viewed from the top, and  FIG. 15B  is a cross-sectional view taken along the line K-K of  FIG. 15A . In addition, in  FIGS. 15A and 15B , for convenience of description of an inner configuration of the quartz crystal oscillator, a state in which the lid member is removed is shown. 
     In a quartz crystal oscillator  501  which is the present modification example, as shown in  FIGS. 15A and 15B , the quartz crystal resonating element  303  which is a modification example of the quartz crystal resonating element  3  of the embodiment shown in  FIGS. 3A and 3B  is mounted, and thus the quartz crystal oscillator  501  is different from the quartz crystal oscillator  5  of the embodiment shown in  FIGS. 5A and 5B  in a partial configuration of a package main body  60   b . In addition, description of the same configuration as the quartz crystal oscillator  5  of the embodiment shown in  FIGS. 5A and 5B  will be omitted. 
     The quartz crystal oscillator  501  includes a package main body  60   b , a lid member  70 , the quartz crystal resonating element  303 , and an IC chip  50  in which an oscillation circuit exciting the quartz crystal resonating element  303  is mounted. 
     In the package main body  60   b , an element mounting pad  82  is formed on an upper surface of a third substrate  63   b  in order to electrically connect a shield electrode  340  provided on the intermediate substrate  302  of the quartz crystal resonating element  303  to a ground terminal which is one of mounting terminals  86  of the package main body  60   b . In addition, the mounting terminal  86  which is the ground terminal and the element mounting pad  82  are electrically connected to each other via conductors (not shown) formed inside the first substrate  61  and the third substrate  63   b . The element mounting pads  81  are disposed so as to correspond to the connection terminals  334   a  and  334   b  formed on the intermediate substrate  302  when the quartz crystal resonating element  303  is placed, and the element mounting pad  82  is disposed so as to correspond to a pad electrode  343  formed on the intermediate substrate  302  when the quartz crystal resonating element  303  is placed. 
     The quartz crystal resonating element  303  is joined to the element mounting pads  81  and  82  of the package main body  60   b  by using conductive joining member  42  and joining member  44  such as conductive adhesives in a state in which the connection terminals  334   a  and  334   b  are aligned with the pad electrode  343 . 
     The quartz crystal oscillator  501  in which the quartz crystal resonating element  303  having the shield electrode  340  is mounted can prevent a floating capacitance between electrodes of the excitation electrode  20   b  of the quartz crystal resonator element  1  and the electrode pattern  330  for inductance or the excitation electrode  20   b  of the quartz crystal resonator element  1  and the IC chip  50 , and thus has stable oscillation characteristics. Therefore, it is possible to provide a quartz crystal oscillator with a large frequency variable width. 
     Modification Example 1 of Quartz Crystal Resonator Element 
       FIGS. 16A and 16B  show a modification example of the quartz crystal resonator element, in which  FIG. 16A  is a schematic plan view when a structure of a quartz crystal resonator element according to a fifth embodiment of the invention is viewed from the top, and  FIG. 16B  is a cross-sectional view taken along the line L-L of  FIG. 16A . 
     A quartz crystal resonator element  101  which is a modification example of the quartz crystal resonator element  1  of the embodiment shown in  FIGS. 1A and 1B  includes, as shown in  FIG. 16A , a quartz crystal substrate  110 , excitation electrodes  120   a  and  120   b , and external connection terminals  122   a  and  122   b . The quartz crystal substrate  110  includes a support portion  114  which is a fixed end and a vibrating portion  112  which is a free end. Here, the vibrating portion  112  according to the present modification example indicates a region which is interposed between mesa portions  116  formed on both main surfaces of the quartz crystal substrate  110 . In addition, the support portion  114  indicates a region between the vibrating portion  112  and the fixed end (the left side) of the quartz crystal resonator element  101 . A pair of excitation electrodes  120   a  and  120   b  are provided so as to be opposite to each other on both main surfaces of the vibrating portion  112 . In addition, the external connection terminals  122   a  and  122   b  which respectively correspond to the excitation electrodes  120   a  and  120   b  are provided on both main surfaces of the support portion  114 , and the excitation electrodes  120   a  and  120   b  are respectively electrically connected to the corresponding external connection terminals  122   a  and  122   b  via lead electrodes  121   a  and  121   b . In addition, the external connection terminals  122   a  and  122   b  provided so as to be opposite to each other on both the main surfaces of the support portion  114  are respectively electrically connected to each other via side electrodes  123   a  and  123   b.    
     Since the quartz crystal resonator element  101  has a mesa structure in which the mesa portions  116  are formed on both main surfaces of the quartz crystal substrate  110 , coupling with a spurious profile can be prevented, and thus vibration energy of only the main vibration can be confined. Therefore, it is possible to reduce CI and to thereby suppress a spurious frequency around a resonance frequency. 
     Modification Example 4 of Quartz Crystal Resonating Element 
       FIGS. 17A and 17B  show a modification example of the quartz crystal resonating element, in which  FIG. 17A  is a schematic plan view when a structure of the quartz crystal resonating element according to the fifth embodiment of the invention is viewed from the top, and  FIG. 17B  is a cross-sectional view taken along the line M-M of  FIG. 17A . 
     As shown in  FIGS. 17A and 17B , a quartz crystal resonating element  304  according to the present modification example is formed by mounting a quartz crystal resonator element  101  which is a modification example of the quartz crystal resonator element  1  of the embodiment shown in  FIGS. 1A and 1B  on the intermediate substrate  2 . The terminals  32   a  and  32   b  for joining to the quartz crystal resonator element  101  provided on one main surface of the intermediate substrate  2  are aligned with the corresponding external connection terminals  122   a  and  122   b  of the quartz crystal resonator element  101  and are joined thereto via a joining member  40 . In addition, the vibrating portion  112  of the quartz crystal resonator element  101  is disposed with a gap by the joining member  40  with respect to one main surface of the intermediate substrate  2  on which the electrode pattern  30  for inductance is formed. 
     Since, in the quartz crystal resonating element  304 , the mesa portions  116  are formed in the vibrating portion  112  of the quartz crystal resonator element  101 , coupling with a spurious profile can be prevented, and thus vibration energy of only the main vibration can be confined. Therefore, it is possible to provide a resonating element in which CI is small and a spurious frequency around a resonance frequency is suppressed. 
     Modification Example 2 of Quartz Crystal Resonator Element 
       FIGS. 18A and 18B  show a modification example of the quartz crystal resonator element, in which  FIG. 18A  is a schematic plan view when a structure of a quartz crystal resonator element according to a sixth embodiment of the invention is viewed from the top, and  FIG. 18B  is a cross-sectional view taken along the line O-O of  FIG. 18A . 
     A quartz crystal resonator element  201  which is a modification example of the quartz crystal resonator element  1  of the embodiment shown in  FIGS. 1A and 1B  includes, as shown in  FIG. 18A , a quartz crystal substrate  210 , excitation electrodes  220   a  and  220   b , and external connection terminals  222   a  and  222   b . The quartz crystal substrate  210  includes a support portion  214  which is a fixed end and a vibrating portion  212  which is a free end. Here, the vibrating portion  212  according to the present modification example indicates a region which is interposed between a bottom of a recess  216  formed on one main surface of the quartz crystal substrate  210  and a main surface on a side where the recess  216  is not formed. In addition, the support portion  214  is the thick portion interposed between both main surfaces of the quartz crystal substrate  210  and indicates a region between the vibrating portion  212  and the fixed end (the left side) of the quartz crystal resonator element  201 . A pair of excitation electrodes  220   a  and  220   b  are provided so as to be opposite to each other on both main surfaces of the vibrating portion  212 . In addition, the external connection terminals  222   a  and  222   b  which respectively correspond to the excitation electrodes  220   a  and  220   b  are provided on both main surfaces of the support portion  214 , and the excitation electrodes  220   a  and  220   b  are respectively electrically connected to the corresponding external connection terminals  222   a  and  222   b  via lead electrodes  221   a  and  221   b . In addition, the external connection terminals  222   a  and  222   b  provided so as to be opposite to each other on both the main surfaces of the support portion  214  are respectively electrically connected to each other via side electrodes  223   a  and  223   b.    
     Since the quartz crystal resonator element  201  has a reverse mesa structure in which the recess  216  is formed in the vibrating portion  212 , the vibrating portion  212  can be made to be very thin so as to achieve a high frequency. In addition, since mounting is performed on the thick part which is integrally formed with the vibrating portion  212 , good resistance to impact or resistance to vibration can be expected. 
     Modification Example 5 of Quartz Crystal Resonating Element 
       FIGS. 19A and 19B  show a modification example of the quartz crystal resonating element, in which  FIG. 19A  is a schematic plan view when a structure of the quartz crystal resonating element according to the sixth embodiment of the invention is viewed from the top, and  FIG. 19B  is a cross-sectional view taken along the line P-P of  FIG. 19A . 
     As shown in  FIGS. 19A and 19B , a quartz crystal resonating element  305  according to the present modification example is formed by mounting a quartz crystal resonator element  201  which is a modification example of the quartz crystal resonator element  1  of the embodiment shown in  FIGS. 1A and 1B  on the intermediate substrate  2 . The terminals  32   a  and  32   b  for joining to the quartz crystal resonator element  201  provided on one main surface of the intermediate substrate  2  are aligned with the corresponding external connection terminals  222   a  and  222   b  of the quartz crystal resonator element  201  and are joined thereto via a joining member  40 . In addition, the vibrating portion  212  of the quartz crystal resonator element  201  is disposed with a gap by the joining member  40  with respect to one main surface of the intermediate substrate  2  on which the electrode pattern  30  for inductance is formed. 
     Since, in the quartz crystal resonating element  305 , since the recess  216  is formed in the vibrating portion  212  of the quartz crystal resonator element  201 , it is possible to provide a resonating element of a high frequency, and since mounting can be performed on the thick part which is integrally formed with the vibrating portion  212 , it is possible to provide a resonating element with good resistance to impact or resistance to vibration. 
     Next, with reference to  FIGS. 20 to 22 , a detailed description will be made of electronic apparatuses to which the quartz crystal resonating element which is an example of the resonating element according to the first embodiment of the invention is applied. 
       FIG. 20  is a perspective view illustrating a configuration of a mobile type (or a notebook type) personal computer as an electronic apparatus including the quartz crystal resonating element which is an example of the resonating element according to the first embodiment of the invention. In  FIG. 20 , a personal computer  1100  is constituted by a main body portion  1104  having a keyboard  1102  and a display unit  1106  having a display portion  100 , and the display unit  1106  is supported so as to be rotatably moved with respect to the main body portion  1104  via a hinge structure portion. The personal computer  1100  includes the quartz crystal resonating element  3 , embedded therein, which functions as a filter, a resonator, a reference clock and the like. 
       FIG. 21  is a perspective view illustrating a configuration of a mobile phone (including PHS) as an electronic apparatus including the quartz crystal resonating element which is an example of the resonating element according to the first embodiment of the invention. In  FIG. 21 , a mobile phone  1200  includes a plurality of operation buttons  1202 , an earpiece  1204 , and a mouthpiece  1206 , and a display portion  100  is disposed between the operation buttons  1202  and the mouthpiece  1204 . The mobile phone  1200  includes the quartz crystal resonating element  3 , embedded therein, which functions as at least one of a filter, a resonator, and the like. 
       FIG. 22  is a perspective view illustrating a configuration of a digital camera as an electronic apparatus including the quartz crystal resonating element which is an example of the resonating element according to the first embodiment of the invention. In addition, in  FIG. 22 , connection to an external apparatus is also briefly shown. Here, a typical camera exposes a silver halide photography film to light using a light image of a subject, whereas the digital camera  1300  performs photoelectric conversion on a light image of a subject by using an imaging device such as a Charge Coupled Device (CCD) so as to generate an imaging signal (image signal). 
     A display portion  100  is provided on a rear side of a case (body)  1302  of the digital camera  1300  and performs display on the basis of an imaging signal generated by the CCD, and the display portion  100  functions a finder which displays a subject as an electronic image. In addition, a light sensing unit  1304  which includes an optical lens (imaging optical system), a CCD, and the like is provided on a front side (the rear side in  FIG. 22 ) of the case  1302 . 
     When a photographer confirms a subject image displayed on the display portion  100  and presses a shutter button  1306 , an imaging signal of the CCD at this point is transmitted to and stored in a memory  1308 . In addition, in this digital camera  1300 , video signal output terminals  1312  and input and output terminals  1314  for data communication are provided on a side surface of the case  1302 . Further, as shown in  FIG. 22 , the video signal output terminals  1312  are connected to a television monitor  1430  and the input and output terminals  1314  for data communication are connected to a personal computer (PC)  1440  as necessary. Furthermore, an imaging signal stored in the memory  1308  is output to the television monitor  1430  or the personal computer  1440  through a predetermined operation. The digital camera  1300  includes the quartz crystal resonating element  3 , embedded therein, which functions as a filter, a resonator, and the like. 
     Further, in addition to the personal computer (a mobile type personal computer) of  FIG. 20 , the mobile phone of  FIG. 21 , and the digital camera of  FIG. 22 , the electronic apparatus including the quartz crystal resonating element which is an example of the resonating element according to the first embodiment of the invention is applicable to, for example, an inkjet type ejection apparatus (for example, an ink jet printer), a laptop type personal computer, a television, a video camera, a video tape recorder, a car navigation apparatus, a pager, an electronic organizer (including a communication function), an electronic dictionary, an electronic calculator, an electronic gaming machine, a word processor, a workstation, a videophone, a security television monitor, an electronic binocular, a POS terminal, a medical apparatus (for example, an electronic thermometer, a sphygmomanometer, a blood glucose monitoring system, an electrocardiographic apparatus, an ultrasonic diagnostic apparatus, or an electronic endoscope), a fish-finder, various measurement apparatuses, meters and gauges (for example, meters and gauges of vehicles, aircrafts, and ships), a flight simulator, and the like. 
       FIG. 23  is a perspective view schematically illustrating an automobile  2106  which is a specific example of a moving body. In  FIG. 23 , the quartz crystal resonating element  3  is embedded in an electronic control unit  2108  which controls tires  2109 , and is mounted in a car body  2107 . 
     The resonator or the electronic device having the resonating element according to the embodiments of the invention is mounted in the automobile  2106 , and is widely applicable to the electronic control unit (ECU)  2108  such as a keyless entry, an immobilizer, a car navigation system, a car air conditioner, an antilock brake system (ABS), an air bag, a tire pressure monitoring system (TPMS), engine control, a battery monitor of a hybrid car or an electric car, and a vehicle dynamic control system.