WO2021186790A1 - 水晶振動素子、水晶振動子及び水晶発振器 - Google Patents

水晶振動素子、水晶振動子及び水晶発振器 Download PDF

Info

Publication number
WO2021186790A1
WO2021186790A1 PCT/JP2020/041942 JP2020041942W WO2021186790A1 WO 2021186790 A1 WO2021186790 A1 WO 2021186790A1 JP 2020041942 W JP2020041942 W JP 2020041942W WO 2021186790 A1 WO2021186790 A1 WO 2021186790A1
Authority
WO
WIPO (PCT)
Prior art keywords
crystal
axis
electrode
thickness
piece
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2020/041942
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
西村　俊雄
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Murata Manufacturing Co Ltd
Original Assignee
Murata Manufacturing Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Murata Manufacturing Co Ltd filed Critical Murata Manufacturing Co Ltd
Priority to DE112020006422.0T priority Critical patent/DE112020006422T5/de
Priority to JP2022508046A priority patent/JP7369363B2/ja
Publication of WO2021186790A1 publication Critical patent/WO2021186790A1/ja
Priority to US17/940,133 priority patent/US20230006645A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/15—Constructional features of resonators consisting of piezoelectric or electrostrictive material
    • H03H9/17—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator
    • H03H9/19—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator consisting of quartz
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
    • H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
    • H03H3/02—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/02007—Details of bulk acoustic wave devices
    • H03H9/02015—Characteristics of piezoelectric layers, e.g. cutting angles
    • H03H9/02023—Characteristics of piezoelectric layers, e.g. cutting angles consisting of quartz
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/05—Holders or supports
    • H03H9/0538—Constructional combinations of supports or holders with electromechanical or other electronic elements
    • H03H9/0547—Constructional combinations of supports or holders with electromechanical or other electronic elements consisting of a vertical arrangement
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic elements; Electromechanical resonators
    • H03H9/02—Details
    • H03H9/05—Holders or supports
    • H03H9/10—Mounting in enclosures
    • H03H9/1007—Mounting in enclosures for bulk acoustic wave [BAW] devices
    • H03H9/1014—Mounting in enclosures for bulk acoustic wave [BAW] devices the enclosure being defined by a frame built on a substrate and a cap, the frame having no mechanical contact with the BAW device
    • H03H9/1021—Mounting in enclosures for bulk acoustic wave [BAW] devices the enclosure being defined by a frame built on a substrate and a cap, the frame having no mechanical contact with the BAW device the BAW device being of the cantilever type

Definitions

  • the present invention relates to a crystal vibrating element, a crystal oscillator, and a crystal oscillator.
  • Oscillators are used in various electronic devices such as mobile communication terminals, communication base stations, and home appliances for applications such as timing devices, sensors, and oscillators. With the increasing functionality of electronic devices, small and thin vibrating elements are required.
  • Patent Document 1 discloses a double-rotating Y-cut crystal vibrating element having good frequency-temperature characteristics in a region higher than room temperature.
  • the thickness of the crystal piece is large and the ratio of the thickness of the electrode to the thickness of the crystal piece is small, so the influence of the electrode can be ignored when considering the frequency temperature characteristics.
  • the ratio of the thickness of the electrode to the crystal piece is large, and the electrode affects the frequency temperature characteristic. Therefore, the frequency-temperature characteristics of the crystal vibrating element and the AT-cut crystal vibrating element described in Patent Document 1 may deteriorate in the high-frequency region.
  • the present invention has been made in view of such circumstances, and an object of the present invention is to provide a crystal vibrating element, a crystal oscillator, and a crystal oscillator having good frequency temperature characteristics.
  • the surface including the X-axis and the Z-axis of the quartz crystal having the X-axis, the Y-axis and the Z-axis as the crystal axes is rotated by ⁇ degrees around the Z-axis, and further X.
  • a crystal piece whose main surface is a surface obtained by rotating the axis by ⁇ degrees around the X'axis, which is rotated by ⁇ degrees, and an electrode provided in contact with the crystal piece are provided, and the thickness of the crystal piece is T.
  • the surface of the quartz crystal having the X-axis, the Y-axis and the Z-axis as the crystal axes including the X-axis and the Z-axis is rotated by ⁇ degrees around the Z-axis, and further X
  • a crystal piece whose main surface is a surface obtained by rotating the axis by ⁇ degrees around the X'axis, which is rotated by ⁇ degrees, and an electrode provided in contact with the crystal piece are provided, and the thickness of the crystal piece is T.
  • Each drawing has a Cartesian coordinate system consisting of the X'axis, Y'axis and Z'axis for convenience to clarify the relationship between the drawings and to help understand the positional relationship of each member. May be attached.
  • the X'axis, Y'axis and Z'axis correspond to each other in the drawings.
  • the X'axis is an axis obtained by rotating the X axis once
  • the Y'axis is an axis obtained by rotating the Y axis twice
  • the Z'axis is obtained by rotating the Z axis once. Is the axis to be.
  • the X-axis, Y-axis, and Z-axis correspond to the crystallographic axes of the quartz crystal, respectively.
  • the X-axis corresponds to the electric axis (polar axis) of the crystal
  • the Y-axis corresponds to the mechanical axis of the crystal
  • the Z-axis corresponds to the optical axis of the crystal. Details of the X'axis, Y'axis and Z'axis will be described later.
  • the direction parallel to the X'axis is the "X'axis direction”
  • the direction parallel to the Y “axis is the” Y “axis direction
  • the direction parallel to the Z'axis is the "Z'axis direction”.
  • the direction of the tip of the arrow on the X'axis, Y'axis and Z'axis is called “+ (plus)”
  • the direction opposite to the arrow is called “-(minus)”.
  • the surface specified by the X'axis and the Y'axis is referred to as an "X'Y" surface. The same applies to the surfaces specified by other axes.
  • the + Y ′′ axial direction will be described as an upward direction
  • the ⁇ Y ′′ axial direction will be described as a downward direction
  • the vertical orientations of the crystal vibrating element 10, the crystal oscillator 1, and the crystal oscillator 100 are limited to this. It is not something that is done.
  • FIG. 1 is an exploded perspective view schematically showing the configuration of the crystal oscillator according to the first embodiment.
  • FIG. 2 is a cross-sectional view schematically showing the configuration of the crystal oscillator according to the first embodiment.
  • FIG. 2 shows a cross section parallel to the X'Y'plane.
  • the crystal oscillator 100 includes a crystal oscillator 1, an external substrate 130, an external cap 140, a sealing frame 150, a solder 153, a capacitor 156, an IC chip 160, a die bonding material 163, and a bonding wire 166.
  • the crystal oscillator 1, solder 153, capacitor 156, IC chip 160, die bonding material 163, and bonding wire 166 are sealed in a space formed between the external substrate 130 and the external cap 140. This space is, for example, liquid-tightly sealed, but may be hermetically sealed in a vacuum state, or may be hermetically sealed in a state filled with a gas such as an inert gas.
  • the crystal oscillator 1 is a kind of piezoelectric vibrator (Piezoelectric Resonator Unit), and is a crystal oscillator (Quartz Crystal Resnotor Unit) provided with a crystal vibrating element (Quartz Crystal Resnotor).
  • the crystal vibrating element uses a crystal piece (Quartz Crystal Element) as a piezoelectric piece excited by the piezoelectric effect.
  • the crystal oscillator 1 is mounted on the external substrate 130 and is sealed in a space formed between the external substrate 130 and the external cap 140.
  • the external substrate 130 is a flat plate-shaped circuit board having an upper surface 131A and a lower surface 131B facing each other.
  • the external substrate 130 is provided using, for example, alumina.
  • a wiring layer is provided on the upper surface 131A, and terminals (not shown) are provided on the lower surface 131B.
  • a casting electrode provided by metallizing a semi-through hole is provided on the side surface of the external substrate 130, and the wiring layer on the upper surface 131A and the terminal on the lower surface 131B are electrically connected by the casting electrode. ing.
  • the outer cap 140 has a bottomed opening for accommodating the crystal oscillator 1 on the side of the outer substrate 130.
  • the outer cap 140 has a flat top wall portion and a side wall portion extending from the outer edge of the top wall portion toward the outer substrate 130.
  • the top wall portion faces the external substrate 130 with the crystal oscillator 1 interposed therebetween, and the side wall portion surrounds the crystal oscillator 1 in a plane direction parallel to the upper surface 131A of the external substrate 130.
  • the sealing frame 150 joins the outer substrate 130 and the outer cap 140. Specifically, the upper surface 131A of the outer substrate 130 and the tip of the side wall of the outer cap 140 are joined.
  • the sealing frame 150 is provided in a rectangular frame shape, and surrounds the crystal oscillator 1, the capacitor 156, the IC chip 160, and the like when the upper surface 131A of the external substrate 130 is viewed in a plan view.
  • the sealing frame 150 is provided, for example, with an electrically insulating resin adhesive.
  • the capacitor 156 is mounted on the upper surface 131A of the external board 130.
  • the capacitor 156 is electrically connected to the crystal oscillator 1 or the IC chip 160 through the wiring layer of the external substrate 130.
  • the capacitor 156 is, for example, a part of an oscillation circuit that oscillates the crystal oscillator 1.
  • the solder 153 joins the wiring layer of the external board 130 and the crystal oscillator 1, and joins the wiring layer of the external board 130 and the capacitor 156.
  • the IC chip 160 is mounted on, for example, the crystal oscillator 1.
  • the IC chip 160 is an ASIC (application specific integrated circuit) having an oscillation circuit of the crystal oscillator 1.
  • the IC chip 160 is, for example, a part of a circuit that corrects the temperature characteristics of the crystal oscillator 1.
  • the die bond material 163 joins the crystal oscillator 1 and the IC chip 160.
  • the die bond material 163 is provided by, for example, a resin adhesive.
  • the die bond material 163 has conductivity, and the crystal oscillator 1 is grounded through the die bond material 163.
  • the die bond material 163 preferably contains a low elasticity resin, for example, a silicone-based resin. According to this, the stress acting on the IC chip 160 can be relaxed.
  • the die bond material 163 is preferably provided by a material having high thermal conductivity. According to this, the temperature followability of the IC chip 160 with respect to the temperature of the crystal oscillator 1 is enhanced.
  • the bonding wire 166 electrically connects the IC chip 160 to the wiring layer of the external board 130.
  • the crystal oscillator 100 shows an example including a crystal oscillator 1 having a crystal vibrating element 10 according to an embodiment of the present invention, and the present invention is limited to the configurations shown in FIGS. 1 and 2. It's not a thing.
  • the outer substrate 130 may have a box shape having a recess capable of accommodating the crystal oscillator 1, and the outer cap 140 may have a flat plate shape.
  • the IC chip 160 may be provided on the external substrate 130 or the external cap 140, or at least a part of the oscillation circuit may be built in the crystal oscillator 1. Further, some of the parts shown in FIGS. 1 and 2 may be omitted, and parts not shown in FIGS. 1 and 2 may be provided.
  • the crystal oscillator 100 may further include a constant temperature bath that keeps the temperature of the crystal oscillator 1 constant.
  • FIG. 3 is an exploded perspective view schematically showing the structure of the crystal unit according to the first embodiment.
  • FIG. 4 is a cross-sectional view schematically showing the configuration of the crystal oscillator according to the first embodiment.
  • FIG. 4 shows a cross section parallel to the X'Y'plane.
  • the crystal oscillator 1 includes a crystal vibrating element 10, a base member 30, a lid member 40, and a joining member 50.
  • the crystal vibrating element 10 is provided between the base member 30 and the lid member 40.
  • the base member 30 and the lid member 40 form a cage for accommodating the crystal vibrating element 10.
  • the base member 30 has a flat plate shape, and the crystal vibrating element 10 is housed in the recess 49 of the lid member 40.
  • the shapes of the base member 30 and the lid member 40 are not limited to the above as long as at least the excited portion of the crystal vibrating element 10 is housed in the cage.
  • the base member 30 may have a recess on the side of the lid member 40 that accommodates at least a part of the crystal vibrating element 10.
  • the crystal vibrating element 10 is an element that vibrates a crystal by a piezoelectric effect and converts electrical energy and mechanical energy.
  • the crystal vibrating element 10 includes a flaky crystal piece 11, a first excitation electrode 14a and a second excitation electrode 14b constituting a pair of excitation electrodes, and a first extraction electrode 15a and a second extraction electrode forming a pair of extraction electrodes. It includes an electrode 15b, and a first connection electrode 16a and a second connection electrode 16b forming a pair of connection electrodes.
  • the crystal piece 11 has an upper surface 11A and a lower surface 11B facing each other.
  • the upper surface 11A is located on the side opposite to the side facing the base member 30, that is, the side facing the top wall portion 41 of the lid member 40 described later.
  • the lower surface 11B is located on the side facing the base member 30.
  • the upper surface 11A and the lower surface 11B correspond to a pair of main surfaces of the crystal piece 11.
  • the main surfaces 11A and 11B of the crystal piece 11 are planes parallel to the X'Z'plane.
  • the crystal piece 11 is formed by etching a crystal substrate (for example, a crystal wafer) obtained by cutting and polishing a crystal of artificial quartz (Synthetic Quartz Crystal).
  • the main vibration of the crystal vibrating element 10 using the crystal piece 11 is a thickness slip vibration mode (Thickness Shear Vibration Mode).
  • the main surface of the crystal piece 11 is not limited to a flat surface as long as it can be obtained from the X'Z'plane, and may be a curved surface such as a concave surface or a convex surface, or an inclined surface inclined with respect to the X'Z'plane. ..
  • the main surface of the crystal piece 11 may be a combination of a flat surface, a curved surface, and an inclined surface.
  • the crystal piece 11 has a thickness parallel to the long side direction in which the long side parallel to the X'axis direction extends, the short side direction in which the short side parallel to the Z'axis direction extends, and the thickness parallel to the Y'axis direction. It is a plate shape having a thickness direction in which is extended. When the upper surface 11A of the crystal piece 11 is viewed in a plane, the plane shape of the crystal piece 11 is rectangular.
  • the crystal piece 11 When the upper surface 11A of the crystal piece 11 is viewed in a plan view, the crystal piece 11 is located at the center and contributes to excitation, an excitation portion 17, a peripheral portion 18 adjacent to the excitation portion 17, and a connection portion connected to the base member 30. Has 19 and.
  • the excitation portion 17 is provided in a rectangular island shape and is surrounded by a frame-shaped peripheral portion 18.
  • the connecting portion 19 is located at the end of the crystal piece 11 on the + X axis direction, and is provided in a pair of rectangular islands arranged along the Z'axis direction.
  • the connecting portion 19 is separated from the exciting portion 17, and a peripheral portion 18 is located between the exciting portion 17 and the connecting portion 19.
  • the planar shape of the crystal piece 11 when the upper surface 11A is viewed in a plane is not limited to a rectangular shape.
  • the planar shape of the crystal piece 11 may be a polygonal shape, a circular shape, an elliptical shape, or a combination thereof.
  • the planar shape of the exciting portion 17 is not limited to a rectangular shape
  • the planar shape of the peripheral portion 18 is not limited to a frame shape.
  • the excitation portion 17 and the peripheral portion 18 may be formed in a band shape over the entire width along the Z'axis direction of the crystal piece 11, respectively.
  • the planar shape of the connecting portion 19 is not limited to a pair of rectangular islands.
  • the planar shape of the connecting portion 19 may be a polygonal shape, a circular shape, an elliptical shape, or a combination thereof. Further, the connecting portion 19 may be provided in a continuous band shape extending along the Z'axis direction. In other words, both the first connection electrode 16a and the second connection electrode 16b may be provided in one connection portion 19.
  • the exciting portion 17 has an upper surface 17A and a lower surface 17B
  • the peripheral portion 18 has an upper surface 18A and a lower surface 18B
  • the connecting portion 19 has an upper surface 19A and a lower surface 19B.
  • the upper surfaces 17A, 18A, and 19A are each a part of the upper surface 11A of the crystal piece 11.
  • the lower surfaces 17B, 18B, and 19B are each a part of the lower surface 11B of the crystal piece 11.
  • the upper surface 17A and the lower surface 17B correspond to a pair of main surfaces of the crystal piece 11 in the exciting portion 17.
  • the upper surface 18A and the lower surface 18B correspond to a pair of main surfaces of the crystal piece 11 in the peripheral portion 18.
  • the upper surface 19A and the lower surface 19B correspond to a pair of main surfaces of the crystal piece 11 at the connecting portion 19.
  • the upper surfaces 17A, 18A, 19A and the lower surfaces 17B, 18B, 19B are X'Z'planes, respectively.
  • the crystal piece 11 has a so-called mesa-shaped structure in which the thickness of the exciting portion 17 is larger than the thickness of the peripheral portion 18. According to the crystal piece 11 having a mesa-shaped structure in the excitation unit 17, vibration leakage of the crystal vibrating element 10 can be suppressed.
  • the crystal piece 11 has a double-sided mesa-shaped structure, and the excitation portions 17 project from the peripheral portions 18 on both sides of the upper surface 11A and the lower surface 11B.
  • the boundary between the exciting portion 17 and the peripheral portion 18 has a tapered shape in which the thickness continuously changes.
  • the surfaces connecting the upper surfaces 17A and 18A of the excitation portion 17 and the peripheral portions 18 and the surfaces connecting the lower surfaces 17B and 18B are inclined surfaces having a uniform inclination.
  • the boundary between the exciting portion 17 and the peripheral portion 18 may form a staircase shape in which the change in thickness is discontinuous.
  • the boundary may have a convex structure in which the amount of change in thickness changes continuously, or a bevel structure in which the amount of change in thickness changes discontinuously.
  • the surface connecting the upper surfaces 17A and 18A of the excitation portion 17 and the peripheral portions 18 and the surface connecting the lower surfaces 17B and 18B, respectively may be composed of a plurality of inclined surfaces or may include a curved surface.
  • the exciting portion 17 may have a single-sided mesa-shaped structure protruding from the peripheral portion 18 on one side of the upper surface 11A or the lower surface 11B of the crystal piece 11.
  • the crystal piece 11 may have a so-called inverted mesa type structure in which the thickness of the exciting portion 17 is smaller than the thickness of the peripheral portion 18.
  • the crystal piece 11 may have a flat plate shape in which the thickness of the exciting portion 17 and the thickness of the peripheral portion 18 are substantially equal to each other.
  • the crystal piece 11 has a mesa-shaped structure at the connecting portion 19 like the exciting portion 17.
  • the thickness of the connecting portion 19 is larger than the thickness of the peripheral portion 18.
  • the bonding strength of the crystal vibrating element 10 with the conductive holding members 36a and 36b is improved.
  • the mesa-shaped structure in the connecting portion 19 is simultaneously formed by the same process as the mesa-shaped structure in the exciting portion 17.
  • a hole or groove may be formed in the peripheral portion 18 between the exciting portion 17 and the connecting portion 19. Such a hole or groove can suppress vibration leakage from the exciting portion 17 to the connecting portion 19, and can reduce the equivalent resistance value (CI value) of the crystal vibrating element 10. Further, such a hole or groove can suppress the propagation of stress from the connecting portion 19 to the exciting portion 17, and can suppress the fluctuation of the frequency of the crystal vibrating element 10.
  • the first excitation electrode 14a and the second excitation electrode 14b are a pair of electrodes that apply a voltage to the excitation portion 17 of the crystal piece 11.
  • the first excitation electrode 14a is provided on the upper surface 17A of the excitation portion 17, and the second excitation electrode 14b is provided on the lower surface 17B of the excitation portion 17.
  • the first excitation electrode 14a and the second excitation electrode 14b face each other with the crystal piece 11 interposed therebetween.
  • the first excitation electrode 14a and the second excitation electrode 14b each have a rectangular shape, and are arranged so that substantially the entire surface of the crystal piece 11 overlaps with each other.
  • the planar shapes of the first excitation electrode 14a and the second excitation electrode 14b when the upper surface 11A of the crystal piece 11 is viewed in a plan view are not limited to a rectangular shape.
  • the plane shape of each of the first excitation electrode 14a and the second excitation electrode 14b may be a polygonal shape, a circular shape, an elliptical shape, or a combination thereof.
  • the first extraction electrode 15a is provided on the upper surface 18A of the peripheral portion 18, and the second extraction electrode 15b is provided on the lower surface 18B of the peripheral portion 18.
  • the first extraction electrode 15a electrically connects the first excitation electrode 14a and the first connection electrode 16a.
  • the second extraction electrode 15b electrically connects the second excitation electrode 14b and the second connection electrode 16b.
  • One end of the first extraction electrode 15a is connected to the first excitation electrode 14a at the excitation portion 17, and the other end of the first extraction electrode 15a is connected to the first connection electrode 16a at the connection portion 19.
  • one end of the second extraction electrode 15b is connected to the second excitation electrode 14b at the excitation portion 17, and the other end of the second extraction electrode 15b is connected to the second connection electrode 16b at the connection portion 19.
  • the first connection electrode 16a and the second connection electrode 16b are provided on the lower surface 19B of the connection portion 19, respectively.
  • the first connection electrode 16a and the second connection electrode 16b are also provided on the upper surface 19A of the connection portion 19 and the side surface of the crystal piece 11.
  • One electrode group including the first excitation electrode 14a, the first extraction electrode 15a, and the first connection electrode 16a is formed continuously with each other, for example, integrally with each other.
  • the other electrode group including the second excitation electrode 14b, the second extraction electrode 15b, and the second connection electrode 16b is also formed continuously with each other, for example, integrally with each other.
  • the crystal vibrating element 10 is provided with a pair of electrodes.
  • the pair of electrodes of the crystal vibrating element 10 has, for example, a multi-layer structure, and the base layer and the outermost layer are laminated in this order.
  • the base layer is a layer that comes into contact with the crystal piece 11, and is provided with a material having good adhesion to the crystal piece 11.
  • the outermost layer is a layer located on the outermost surface of the pair of electrodes, and is provided with a material having good chemical stability.
  • the base layer contains, for example, chromium (Cr), and the outermost layer contains, for example, gold (Au).
  • At least one of the pair of electrodes of the crystal vibrating element 10 may be provided apart from the crystal piece 11. For example, a gap may be provided between the first excitation electrode 14a and the excitation portion 17.
  • the materials constituting the pair of electrodes of the crystal vibrating element 10 are not limited to Cr and Au, and are, for example, titanium (Ti), molybdenum (Mo), aluminum (Al), nickel (Ni), and indium (In). , Palladium (Pd), silver (Ag), copper (Cu), tin (Sn), iron (Fe) and other metallic materials may be contained.
  • the pair of electrodes may contain a conductive ceramic, a conductive resin, a semiconductor, or the like.
  • the thickness T of the crystal piece 11 is the thickness of the exciting portion 17.
  • the thickness T of the crystal piece 11 is, for example, the thickness of the central portion of the exciting portion 17.
  • the thickness ta of the first excitation electrode 14a is the thickness of the central portion of the first excitation electrode 14a
  • the thickness tb of the second excitation electrode 14b is the thickness of the central portion of the second excitation electrode 14b.
  • the thickness t is the thickness of the other electrode provided in contact with the crystal piece 11. equal.
  • the thickness T of the crystal piece 11 and the thickness t of the electrode provided in contact with the crystal piece 11 satisfy the relationship of t / T ⁇ 0.01.
  • the ratio t / T of the thickness t of the electrode to the thickness T of the crystal piece 11 is 0.01 or more.
  • the thickness ratio t / T is preferably 0.02 or more, more preferably 0.05 or more, and even more preferably 0.1 or more. Further, it is desirable that the thickness ratio t / T is 0.5 or less.
  • the thickness sliding vibration mode it is necessary to thin the crystal vibrating element 10 in order to increase the frequency of the crystal vibrating element 10. Since it is difficult to make the electrode provided in contact with the crystal piece 11 thinner than the crystal piece 11, when the crystal vibrating element 10 is made thinner, the thickness ratio t / T becomes larger. Therefore, in order to increase the frequency of the crystal vibrating element 10, it is necessary to increase the thickness ratio t / T. However, the larger the thickness ratio t / T, the greater the influence of the electrode on the frequency temperature characteristics.
  • the base member 30 holds the crystal vibrating element 10 in an excitable manner.
  • the base member 30 includes a substrate 31 having an upper surface 31A and a lower surface 31B facing each other.
  • the upper surface 31A and the lower surface 31B correspond to a pair of main surfaces of the substrate 31.
  • the upper surface 31A is located on the side facing the crystal vibrating element 10 and the lid member 40, and corresponds to a mounting surface on which the crystal vibrating element 10 is mounted.
  • the lower surface 31B is located on the side facing the external substrate 130 and corresponds to a mounting surface to which the external substrate 130 is connected.
  • the substrate 31 is a sintered material such as an insulating ceramic (alumina).
  • the substrate 31 is preferably made of a heat-resistant material.
  • the substrate 31 may be provided by a material having a coefficient of thermal expansion close to that of the crystal piece 11, or may be provided by, for example, quartz. Further, from the viewpoint of suppressing damage to the substrate 31 due to thermal stress, the substrate 31 may be provided with a material having a coefficient of thermal expansion close to that of the lid member 40.
  • the base member 30 includes a first electrode pad 33a and a second electrode pad 33b.
  • the first electrode pad 33a and the second electrode pad 33b are provided on the upper surface 31A of the substrate 31.
  • the first electrode pad 33a and the second electrode pad 33b are terminals for electrically connecting the crystal vibrating element 10 to the base member 30.
  • the outermost layers of the first electrode pad 33a and the second electrode pad 33b each contain gold, and it is more desirable that the outermost layers are made of almost only gold.
  • the first electrode pad 33a and the second electrode pad 33b may have a laminated structure having a base layer for improving adhesion to the substrate 31 and a surface layer containing gold and suppressing oxidation.
  • the first electrode pad 33a and the second electrode pad 33b correspond to a pair of electrode pads.
  • the base member 30 includes a first external electrode 35a, a second external electrode 35b, a third external electrode 35c, and a fourth external electrode 35d.
  • the first external electrode 35a to the fourth external electrode 35d are provided on the lower surface 31B of the substrate 31.
  • the first external electrode 35a and the second external electrode 35b are terminals for electrically connecting the wiring layer of the external substrate 130 and the crystal oscillator 1.
  • the third external electrode 35c and the fourth external electrode 35d are, for example, dummy electrodes to which an electric signal or the like is not input / output. good.
  • the third external electrode 35c and the fourth external electrode 35d may be omitted.
  • the first electrode pad 33a is electrically connected to the first external electrode 35a via the first through electrode 34a that penetrates the substrate 31 along the Y ′′ axial direction.
  • the second electrode pad 33b is electrically connected to the second external electrode 35b via the second through electrode 34b that penetrates the substrate 31 along the Y ′′ axial direction.
  • Each of the first electrode pad 33a and the second electrode pad 33b is electrically connected to the first external electrode 35a and the second external electrode 35b via the side electrode provided on the side surface connecting the upper surface 31A and the lower surface 31B of the substrate 31. May be connected.
  • the side electrode may be a casting electrode.
  • the base member 30 includes a first conductive holding member 36a and a second conductive holding member 36b.
  • the first conductive holding member 36a and the second conductive holding member 36b hold the crystal vibrating element 10 in an excitable manner. In other words, the crystal vibrating element 10 is held so that the exciting portion 17 does not come into contact with the base member 30 and the lid member 40.
  • the first conductive holding member 36a and the second conductive holding member 36b electrically connect the crystal vibrating element 10 and the base member 30.
  • the first conductive holding member 36a electrically connects the first electrode pad 33a and the first connecting electrode 16a
  • the second conductive holding member 36b electrically connects the second electrode pad 33b and the second connecting electrode. It is electrically connected to 16b.
  • the first conductive holding member 36a and the second conductive holding member 36b correspond to a pair of conductive holding members.
  • the first conductive holding member 36a and the second conductive holding member 36b are cured products of a conductive adhesive containing a thermosetting resin, a photocurable resin, and the like, and the first conductive holding member 36a and the second conductive.
  • the main component of the property-retaining member 36b is, for example, a silicone resin.
  • the first conductive holding member 36a and the second conductive holding member 36b contain conductive particles, and as the conductive particles, for example, metal particles containing silver (Ag) are used.
  • the main components of the first conductive holding member 36a and the second conductive holding member 36b are not limited to silicone resin as long as they are curable resins, and may be, for example, epoxy resin or acrylic resin. Further, the conductivity of the first conductive holding member 36a and the second conductive holding member 36b is not limited to being imparted by silver particles, but is imparted by other metals, conductive ceramics, conductive organic materials, and the like. You may.
  • the main components of the first conductive holding member 36a and the second conductive holding member 36b may be a conductive polymer.
  • any additive may be contained in the resin composition of the first conductive holding member 36a and the second conductive holding member 36b.
  • the additive is, for example, a tackifier, a filler, a thickener, a sensitizer, an antiaging agent, an antifoaming agent, etc. for the purpose of improving the workability and storage stability of the conductive adhesive.
  • a filler may be added for the purpose of increasing the strength of the cured product or for maintaining the distance between the base member 30 and the crystal vibrating element 10.
  • the lid member 40 is joined to the base member 30.
  • the lid member 40 forms an internal space for accommodating the crystal vibrating element 10 with the base member 30.
  • the lid member 40 has a recess 49 that opens on the side of the base member 30, and the internal space in the present embodiment corresponds to the space inside the recess 49.
  • the recess 49 is sealed in a vacuum state, for example, but may be sealed in a state filled with an inert gas such as nitrogen or a rare gas.
  • the recess 49 may be sealed in a liquid-tight state.
  • the material of the lid member 40 is preferably a conductive material, and more preferably a highly airtight metal material.
  • the lid member 40 is made of a conductive material, the lid member 40 is provided with an electromagnetic shield function that reduces the ingress and egress of electromagnetic waves into the internal space. Further, the IC chip 160 can be grounded through the lid member 40.
  • the material of the lid member 40 is preferably a material having a coefficient of thermal expansion close to that of the substrate 31, for example, the coefficient of thermal expansion near room temperature is in a wide temperature range of glass or ceramic. It is a matching Fe—Ni—Co based alloy.
  • the material of the lid member 40 may be the same as that of the substrate 31, and may include ceramic, crystal, resin, and the like.
  • the lid member 40 has a flat top wall portion 41 and a side wall portion 42 connected to the outer edge of the top wall portion 41 and extending along the height direction.
  • the recess 49 of the lid member 40 is formed by the top wall portion 41 and the side wall portion 42.
  • the top wall portion 41 extends along the upper surface 31A of the substrate 31 and faces the base member 30 with the crystal vibrating element 10 interposed therebetween in the height direction.
  • the side wall portion 42 extends from the top wall portion 41 toward the base member 30, and surrounds the crystal vibrating element 10 in a direction parallel to the upper surface 31A of the base 31.
  • the lid member 40 further has a flange portion 43 that is connected to the tip of the side wall portion 42 on the base member 30 side and extends outward along the upper surface 31A of the substrate 31.
  • the top wall portion 41 connected to the upper end portion of the side wall portion 42 and the flange portion 43 connected to the lower end portion of the side wall portion 42 extend in opposite directions to each other.
  • the flange portion 43 extends in a frame shape so as to surround the crystal vibrating element 10.
  • the joining member 50 is provided over the entire circumference of each of the base member 30 and the lid member 40, and has a rectangular frame shape.
  • the first electrode pad 33a and the second electrode pad 33b are arranged inside the joining member 50, and the joining member 50 is provided so as to surround the crystal vibration element 10. ing.
  • the joining member 50 joins the base member 30 and the lid member 40, and seals the recess 49 corresponding to the internal space. Specifically, the joining member 50 joins the base 31 and the flange portion 43.
  • the material of the joining member 50 has low moisture permeability, and more preferably low gas permeability. Further, in order to electrically connect the lid member 40 to the ground potential via the joining member 50, it is desirable that the joining member 50 has conductivity. From these viewpoints, the material of the joining member 50 is preferably metal.
  • the joining member 50 is a combination of a metallized layer made of molybdenum (Mo) provided on the upper surface 31A of the substrate 31 and a gold tin (Au—Sn) system provided between the metallized layer and the flange portion 43. It is provided by a metal solder layer made of a crystal alloy.
  • the joining member 50 may be provided with an inorganic adhesive such as a silicon-based adhesive containing water glass or the like or a calcium-based adhesive containing cement or the like.
  • the material of the joining member 50 may be provided by an epoxy-based, vinyl-based, acrylic-based, urethane-based, or silicone-based organic adhesive.
  • a coating having a lower gas permeability than the adhesive may be provided on the outside of the joining member 50 in order to reduce the gas permeability.
  • the base member 30 and the lid member 40 may be joined by seam welding.
  • FIG. 5 is a diagram showing the first rotation of the quartz crystal.
  • FIG. 6 is a diagram showing the second rotation angle of the quartz crystal.
  • FIG. 7 is a graph showing the optimum rotation angle of the crystal piece.
  • FIG. 8 is a graph showing the optimum rotation angle of the crystal piece.
  • the crystal piece 11 is formed of a crystal substrate obtained by rotating the Y plate twice.
  • the surface of the quartz crystal including the X-axis and the Z-axis is rotated by ⁇ degrees around the Z-axis.
  • ⁇ degree corresponds to the rotation angle of the first rotation.
  • the direction of the first rotation is a direction in which the positive direction side of the X axis is rotated in the positive direction side of the Y axis, and is a direction that becomes counterclockwise when the XY plane is viewed in a plane from the + Z axis direction.
  • the X'axis and the Y'axis are obtained by first rotating each of the X-axis and the Y-axis.
  • the surface obtained by the first rotation is rotated by ⁇ degrees around the X'axis.
  • the ⁇ degree corresponds to the rotation angle of the second rotation.
  • the direction of the second rotation is the direction in which the positive side of the Y'axis is rotated to the positive side of the Z axis, and the direction is counterclockwise when the Y'Z plane is viewed in a plane from the + X'axis direction. be.
  • the Y ′′ axis and the Z ′ axis are obtained by secondly rotating the Y ′ axis and the Z axis, respectively. In this way, the main surface of the crystal piece 11 is obtained based on the Z'X'plane obtained by rotating the ZX surface twice.
  • the horizontal axis of the graph of FIG. 7 shows the thickness ratio t / T
  • the vertical axis shows the rotation angle ⁇ degree of the first rotation or the rotation angle ⁇ degree of the second rotation.
  • the graph in the figure is a plot of the angles of rotation ⁇ and ⁇ at which the primary and secondary coefficients of the frequency temperature characteristics become zero when the thickness ratio t / T is the variable x. From the approximate expression of the plot, it was found that the rotation angles ⁇ and ⁇ with the primary coefficient and the secondary coefficient of the frequency temperature characteristic set to zero satisfy the following equation.
  • the horizontal axis of the graph of FIG. 8 indicates the rotation angle ⁇ of the second rotation
  • the vertical axis indicates the rotation angle ⁇ of the first rotation.
  • ⁇ 5 The crystal piece 11 is provided so that the relationship of
  • An embodiment is a crystal vibrating element in which a pair of electrodes are provided on both sides of a crystal piece.
  • the crystal piece and the pair of electrodes are rectangular flat plates, respectively.
  • the pair of electrodes is made of aluminum.
  • the area of the main surface of the crystal piece is 120 ⁇ m 2
  • the thickness of the crystal is 1 ⁇ m
  • the area of the main surface of the electrodes is 50 ⁇ m 2
  • the thickness of one of the electrodes is 0.2 ⁇ m
  • the sum of the thicknesses of the pair of electrodes is 0.4 ⁇ m. ..
  • the rotation angle ⁇ of the first rotation is 4.9 degrees
  • the rotation angle ⁇ of the second rotation is 33.4 degrees.
  • Comparative Example 1 and Comparative Example 2 differ only in the angle of rotation from the examples. Specifically, the crystal piece of Comparative Example 1 is AT-cut. In Comparative Example 1, the rotation angle ⁇ is 0 degrees and the rotation angle ⁇ is 35 degrees 25 minutes. The crystal piece of Comparative Example 2 has the AT-cut angle of rotation modified so that the frequency-temperature characteristics are improved. In Comparative Example 2, the rotation angle ⁇ is 0 degrees and the rotation angle ⁇ is 33 degrees 45 minutes.
  • the frequency temperature characteristic of Comparative Example 1 is greatly affected by the electrode because the crystal piece is thin, and is worse than the frequency temperature characteristic of the crystal vibrating element having t / T ⁇ 0.01.
  • the frequency temperature characteristic of Comparative Example 2 is improved by correcting the first-order coefficient as compared with the frequency temperature characteristic of Comparative Example 1. However, it cannot be said that the frequency temperature characteristic of Comparative Example 2 is sufficiently improved, and the frequency change in the high temperature region is large. Since the first-order coefficient and the second-order coefficient of the frequency-temperature characteristic of the example become zero, the temperature change of the frequency in the example is smaller than the temperature change of the frequency in the comparative example 2.
  • the relationship holds.
  • ⁇ 5 holds. According to this, the frequency temperature characteristic is improved.
  • the surface including the X-axis and the Z-axis of the quartz crystal having the X-axis, the Y-axis and the Z-axis as the crystal axes is rotated by ⁇ degrees around the Z-axis, and the X-axis is further rotated by ⁇ degrees.
  • relationship ⁇ 0.5 is satisfied, crystal oscillation element is provided. According to this, the frequency temperature characteristic is improved.
  • the surface including the X-axis and the Z-axis of the quartz crystal having the X-axis, the Y-axis and the Z-axis as the crystal axes is rotated by ⁇ degrees around the Z-axis, and further, the X-axis is further formed.
  • the thickness t of the electrodes provided in contact with the crystal piece is the sum of the thicknesses of each of the pair of electrodes that apply a voltage to the crystal piece.
  • the main vibration of the crystal vibration element is the thickness slip vibration mode.
  • the electrode provided on the quartz piece is made of aluminum.
  • any of the above-mentioned crystal vibrating elements, a base member, and a lid member joined to the base member are provided, and the crystal vibrating element is provided in the internal space between the base member and the lid member. Also, a crystal oscillator is provided.
  • a crystal oscillator including the above-mentioned crystal oscillator and an IC chip having an oscillation circuit of the crystal oscillator is provided.
  • the embodiment according to the present invention can be appropriately applied without particular limitation as long as it is a device that converts electromechanical energy by a piezoelectric effect, such as a timing device, a sounding device, an oscillator, and a load sensor.
  • a crystal vibrating element As described above, according to one aspect of the present invention, it is possible to provide a crystal vibrating element, a crystal oscillator, and a crystal oscillator having good frequency and temperature characteristics.

Landscapes

  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
PCT/JP2020/041942 2020-03-19 2020-11-10 水晶振動素子、水晶振動子及び水晶発振器 Ceased WO2021186790A1 (ja)

Priority Applications (3)

Application Number Priority Date Filing Date Title
DE112020006422.0T DE112020006422T5 (de) 2020-03-19 2020-11-10 Kristallschwingelement, kristallschwinger und kristalloszillator
JP2022508046A JP7369363B2 (ja) 2020-03-19 2020-11-10 水晶振動素子、水晶振動子及び水晶発振器
US17/940,133 US20230006645A1 (en) 2020-03-19 2022-09-08 Quartz crystal resonator, quartz crystal resonator unit and quartz crystal oscillator

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2020049701 2020-03-19
JP2020-049701 2020-03-19

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US17/940,133 Continuation US20230006645A1 (en) 2020-03-19 2022-09-08 Quartz crystal resonator, quartz crystal resonator unit and quartz crystal oscillator

Publications (1)

Publication Number Publication Date
WO2021186790A1 true WO2021186790A1 (ja) 2021-09-23

Family

ID=77771171

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2020/041942 Ceased WO2021186790A1 (ja) 2020-03-19 2020-11-10 水晶振動素子、水晶振動子及び水晶発振器

Country Status (4)

Country Link
US (1) US20230006645A1 (https=)
JP (1) JP7369363B2 (https=)
DE (1) DE112020006422T5 (https=)
WO (1) WO2021186790A1 (https=)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116054776A (zh) * 2022-12-28 2023-05-02 北京无线电计量测试研究所 用于单粒子效应试验的晶振
CN118797965A (zh) * 2024-09-12 2024-10-18 西安电子科技大学 一种石英谐振器线性度的优化设计方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117595826A (zh) * 2023-11-20 2024-02-23 陈庭毅 一种恒温晶体振荡器及其制造方法、电子设备

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07297663A (ja) * 1994-04-28 1995-11-10 Meidensha Corp 厚みすべり水晶振動子の製造方法
JP2002246866A (ja) * 2001-02-20 2002-08-30 Citizen Watch Co Ltd 表面実装型圧電デバイスとその製造方法
JP2019092148A (ja) * 2017-11-16 2019-06-13 日本電波工業株式会社 圧電振動片及び圧電デバイス

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001244778A (ja) 1999-12-22 2001-09-07 Toyo Commun Equip Co Ltd 高周波圧電振動子
JP2003324332A (ja) 2002-02-28 2003-11-14 Toyo Commun Equip Co Ltd ２回回転ｙカット水晶振動子とこれを用いた発振器
JP5378917B2 (ja) 2009-09-09 2013-12-25 日本電波工業株式会社 水晶振動片及び水晶振動デバイス
JP5515921B2 (ja) 2010-03-24 2014-06-11 セイコーエプソン株式会社 恒温型圧電発振器の製造方法
JP2014007538A (ja) 2012-06-25 2014-01-16 Daishinku Corp 水晶振動デバイス

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07297663A (ja) * 1994-04-28 1995-11-10 Meidensha Corp 厚みすべり水晶振動子の製造方法
JP2002246866A (ja) * 2001-02-20 2002-08-30 Citizen Watch Co Ltd 表面実装型圧電デバイスとその製造方法
JP2019092148A (ja) * 2017-11-16 2019-06-13 日本電波工業株式会社 圧電振動片及び圧電デバイス

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116054776A (zh) * 2022-12-28 2023-05-02 北京无线电计量测试研究所 用于单粒子效应试验的晶振
CN118797965A (zh) * 2024-09-12 2024-10-18 西安电子科技大学 一种石英谐振器线性度的优化设计方法

Also Published As

Publication number Publication date
US20230006645A1 (en) 2023-01-05
DE112020006422T5 (de) 2022-11-03
JPWO2021186790A1 (https=) 2021-09-23
JP7369363B2 (ja) 2023-10-26

Similar Documents

Publication Publication Date Title
CN203180862U (zh) 振动片、振子、电子器件以及电子设备
JP5943187B2 (ja) 振動素子、振動子、電子デバイス、および電子機器
US20230006645A1 (en) Quartz crystal resonator, quartz crystal resonator unit and quartz crystal oscillator
CN113765494B (zh) 振子以及振荡器
US11362641B2 (en) Piezoelectric resonator device
US12457903B2 (en) Piezoelectric vibration element, piezoelectric resonator unit, and electronic device
JP2011199228A (ja) 電子部品用パッケージのベース、電子部品用パッケージ
US20230261635A1 (en) Piezoelectric vibration element, piezoelectric vibrator, and piezoelectric oscillator
JP5434712B2 (ja) 圧電振動片および圧電デバイス
JP2008066921A (ja) 圧電振動子
JP4720846B2 (ja) 水晶振動デバイス
JP2007235289A (ja) 圧電発振器
US20250183873A1 (en) Piezoelectric vibration element
WO2022158028A1 (ja) 圧電振動子
US20250293665A1 (en) Piezoelectric resonator, piezoelectric resonator unit, and piezoelectric oscillator
US20250141426A1 (en) Piezoelectric resonator
JP2013197801A (ja) 振動片、振動子、電子デバイス、および電子機器
JP2017112544A (ja) 圧電振動子
JP2023032382A (ja) 電子部品用のベース
JP2018056668A (ja) 素子搭載部材及び圧電デバイス
WO2021215040A1 (ja) 圧電振動子
JP4833716B2 (ja) 圧電発振器
JP2016134800A (ja) 圧電振動片および圧電振動子
WO2021210214A1 (ja) 圧電振動子及びその製造方法
WO2021220542A1 (ja) 圧電振動子

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20925474

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2022508046

Country of ref document: JP

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 20925474

Country of ref document: EP

Kind code of ref document: A1