JP2015126498A - Piezoelectric oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric oscillator in which an output signal is stabilized by reducing the influence of floating capacitance.SOLUTION: A piezoelectric oscillator includes: a substrate 110; external terminals 111 provided on an under surface of the substrate 110; connection pads for terminals, connection pads for elements, and mounting pads 115 that are provided on a top surface of the substrate 110; wiring portions 113 for terminals electrically connecting the external terminals 111 and the connection pads for terminals; wiring portions for elements electrically connecting the connection pads for elements and the mounting pads 115; a vibration element 120 and an integrated circuit element mounted on the substrate 110; a metal lid 140 composed of a sealing base 141 and a sealing frame portion 142 provided along an outer edge of an under surface of the sealing base 141; a junction member 150 provided between the top surface of the substrate 110 and an under surface of the sealing frame portion 142; and a conductive member 170 fixed to the metal lid 140 and one of the wiring portions 113 for terminals.

Description

  The present invention relates to a piezoelectric oscillator built in an electronic device such as a mobile communication device.

  With recent miniaturization of electronic devices such as mobile communication devices, miniaturization of piezoelectric oscillators built into electronic devices such as thinning and area reduction has been promoted. As an example of a miniaturized piezoelectric oscillator, there is one in which a vibration element is mounted on a rectangular substrate, and the vibration element is hermetically sealed by bonding the substrate and a lid with a bonding member (for example, patents) Reference 1).

  A lid used for such a piezoelectric oscillator has a recessed space, for example, and can enclose a vibration element in the recessed space. In addition, the lid is provided with a flange extending from the opening of the recess space so as to surround the recess space. In such a piezoelectric device, the inside of the recessed space is hermetically sealed by joining the bottom surface of the lid body and the upper surface of the substrate with an insulating joint member (see, for example, Patent Document 2). ).

JP 2013-172185 A JP 2012-222537 A

  In the conventional piezoelectric oscillator, since the substrate and the lid are bonded by an insulating bonding material, when the lid is made of metal, or when the vibration element is not covered with the electrostatic shield, A stray capacitance is generated between the excitation electrode and the lid, or between the excitation electrode of the vibration element and the outside of the piezoelectric device. The vibration element applies an alternating voltage to a pair of excitation electrodes, accumulates different charges alternately, and vibrates using the piezoelectric effect and the inverse piezoelectric effect. For this reason, when stray capacitance occurs, stray capacitance is added to the vibration element, the frequency fluctuates, and the output signal may not be stable.

  An object of the present invention is to provide a piezoelectric oscillator in which the influence of stray capacitance is reduced and the output signal is stable.

  In order to solve the above-described problems, a piezoelectric oscillator according to the present invention is provided on a substrate, external terminals provided on the lower surface of the substrate, terminal connection pads provided on the upper surface of the substrate, and the substrate. A terminal wiring portion having one end connected to the external terminal and the other end connected to the terminal connection pad, an element connection pad provided on the upper surface of the substrate side by side with the terminal connection pad, A pair of mounting pads provided on the upper surface and a substrate, one end of which is connected to the element connection pad and the other end is connected to the mounting pad, and the element is connected and fixed to the mounting pad. Vibration element, terminal mounting pad, integrated circuit element connected and fixed to the element mounting pad, sealing base, and sealing frame provided on the outer edge of the lower surface of the sealing base A metal lid made of A joining member provided between the upper surface of the substrate and the lower surface of the sealing frame portion; and a conductive member electrically connected to one of the terminal wiring portions while being electrically connected to the metal lid. It is characterized by comprising.

  In the piezoelectric oscillator of the present invention, the terminal wiring portion is provided on the substrate. One end of the terminal wiring portion is connected to the external terminal, and the other end is connected to the terminal connection pad. Moreover, the predetermined one terminal wiring portion is in a state of being electrically connected to the metal lid by the conductive member. Thus, when the piezoelectric oscillator of the present invention is mounted on a motherboard such as an electronic device, the external terminal electrically connected to the metal lid by the conductive member is connected to the ground potential. By connecting to the mounting pad, the metal lid is set to the same potential as the ground potential, stray capacitance generated between the excitation electrode of the vibration element and the metal cover, or the excitation electrode of the vibration element and the outside of the piezoelectric oscillator As compared with the conventional piezoelectric oscillator, the stray capacitance generated between the two can be reduced, the frequency fluctuation due to the stray capacitance can be suppressed, and the output signal can be stabilized.

It is a top view of the piezoelectric oscillator in this embodiment. It is sectional drawing in AA of FIG. (A) is a top view of the upper surface of the board | substrate used with the piezoelectric oscillator in this embodiment, (b) is a top view of the lower surface of the board | substrate seen through from the upper surface of the board | substrate used with the piezoelectric oscillator in this embodiment. It is a top view of the upper surface of the board | substrate used with the piezoelectric oscillator in the modification of this embodiment, (b) is a top view of the lower surface of the board | substrate seen through from the upper surface of the board | substrate used with the piezoelectric oscillator in the modification of this embodiment. .

  1, 2, and 3, the piezoelectric oscillator according to the present embodiment includes a substrate 110, the vibration element 120 and the integrated circuit element 160 that are mounted on the upper surface of the substrate 110, and a bonding member. 150 and a metal lid 140 that is bonded together by 150 and hermetically seals the vibration element 120. Such a piezoelectric oscillator is used to output a reference signal used in an electronic device or the like.

  Here, in accordance with the drawing, the surface of the substrate 110 on which the vibration element 120 is mounted is the upper surface of the substrate 110, and the surface of the substrate 110 facing away from the upper surface of the substrate 110 is the lower surface of the substrate 110. The upper surface of the substrate 110 and the lower surface of the substrate 110 are defined as the main surface of the substrate 110.

  The substrate 110 has a rectangular flat plate shape, and is used for mounting the vibration element 120 and the integrated circuit element 160 on the upper surface of the substrate 110. The substrate 110 is made of an insulating layer made of a ceramic material such as alumina ceramic or glass-ceramic. In addition, the substrate 110 may be one in which an insulating layer is used as a single layer, or may be a layer in which a plurality of insulating layers are stacked. A plurality of external terminals 111 are provided on the lower surface of the substrate 110, and terminal connection pads 112, element connection pads 114, and mounting pads 115 are provided on the upper surface of the substrate 110. Further, on the substrate 110, a terminal wiring portion 113 for electrically connecting the external terminal 111 and the terminal connection pad 112, and an element wiring portion for electrically connecting the element connection pad 114 and the mounting pad 115. 116 is provided.

  The external terminal 111 is for mounting the piezoelectric oscillator of the present embodiment on a motherboard such as an electronic device, and is connected and fixed to a mounting pad (not shown) on the motherboard. The external terminals 111 include, for example, a first external terminal 111a, a second external terminal 111b, a third external terminal 111c, and a fourth external terminal 111d, and are provided at four corners on the lower surface of the substrate 110, one by one. The first external terminal 111a is connected to the first terminal wiring portion 113a, and is electrically connected to the first terminal connection pad 112a via the first terminal wiring portion 113a. When the first external terminal 111a is mounted on a motherboard such as an electronic device, for example, the first external terminal 111a is fixedly connected to a mounting pad connected to a ground potential that is a reference potential on the motherboard of the electronic device or the like. Accordingly, the first external terminal 111a is, for example, a ground terminal having the same potential as the ground potential. The second external terminal 111b is provided at a position diagonal to the first external terminal 111a, is connected to the second terminal wiring portion 113b, and is connected to the second terminal via the second terminal wiring portion 113b. The electrical connection pad 112b is electrically connected. For example, the second external terminal 111b is used as a power supply voltage terminal to which a power supply voltage for driving the piezoelectric oscillator of the present embodiment is input. The third external terminal 111c is connected to the third terminal wiring portion 113c, and is electrically connected to the third terminal connection pad 112c via the third terminal wiring portion 113c. The third external terminal 111c is used, for example, as an output terminal that outputs a predetermined frequency as a signal voltage. The fourth external terminal 111d is provided at a diagonal position with respect to the third external terminal 111c. The fourth terminal wiring portion 113d is connected to the fourth external terminal 111c, and the fourth terminal wiring portion 113d is connected to the fourth terminal. The electrical connection pad 112d is electrically connected. For example, the fourth external terminal 111d is used as an adjustment voltage terminal to which an adjustment voltage for adjusting the signal voltage output from the third external terminal 111c is input.

  The terminal connection pad 112 is for mounting the integrated circuit element 160. The terminal connection pads 112 are located on the upper surface of the substrate 110 and below the connection terminals (not shown) of the integrated circuit element 160, and are fixed while being electrically connected to the connection terminals. The terminal connection pad 112 is connected to the terminal wiring portion 113 and is electrically connected to the external terminal 111 provided on the lower surface of the substrate 110. Therefore, the connection terminal of the integrated circuit element 160 is in a state of being electrically connected to the external terminal 111 via the terminal connection pad 112 and the terminal wiring portion 113.

  The terminal connection pads 112 include, for example, a first terminal connection pad 112a, a second terminal connection pad 112b, a third terminal connection pad 112c, and a fourth terminal connection pad 112d. The first terminal connection pad 112a and the fourth terminal connection pad 112d are provided along the short side of the substrate 110, and the second terminal connection pad 112b and the third terminal connection pad 112c are The one-terminal connection pad 112a and the fourth terminal connection pad 112d are provided side by side along the short side of the substrate 110 with a space therebetween. The first terminal connection pads 112 a are located on the upper surface of the substrate 110 and below the first connection terminals (not shown) of the integrated circuit element 160. The first terminal connection pad 112a is connected to the first terminal wiring portion 113a and is electrically connected to the first external terminal 111a via the first terminal wiring portion 113a. The second terminal connection pad 112b is provided on the upper surface of the substrate 110 at a position diagonal to the first terminal connection pad 112a, and is a second connection terminal (not shown) of the integrated circuit element 160. Located below. The second terminal connection pad 112b is connected to the second terminal wiring portion 113b, and is electrically connected to the second external terminal 111b via the second terminal wiring portion 113b. The third terminal connection pad 112c is provided so as to be arranged along the short side of the second terminal connection pad 112b and the substrate 110, and a third connection terminal (not shown) of the integrated circuit element 160. Located below. The third terminal connection pad 112c is connected to the third terminal wiring portion 113c, and is electrically connected to the third external terminal 111c via the third terminal wiring portion 113c. The fourth terminal connection pad 112d is provided on the upper surface of the substrate 110 at a position diagonal to the third terminal connection pad 112c, and is a fourth connection terminal (not shown) of the integrated circuit element 160. Located below. The fourth terminal connection pad 112d is connected to the fourth terminal wiring portion 113d, and is electrically connected to the fourth external terminal 111d via the fourth terminal wiring portion 113d.

  The terminal wiring portion 113 is provided on the substrate 110 to electrically connect the external terminal 111 provided on the lower surface of the substrate 110 and the terminal connection pad 112 provided on the upper surface of the substrate 110. belongs to. The terminal wiring portion 113 includes, for example, a first terminal wiring portion 113a, a second terminal wiring portion 113b, a third terminal wiring portion 113c, and a fourth terminal wiring portion 113d.

  The first terminal wiring portion 113a has one end connected to the first external terminal 111a and the other end connected to the first terminal connection pad 112a. The first external terminal 111a and the first terminal connection pad 112a Are electrically connected. In addition, the first terminal wiring portion 113 a is partly provided along the outer edge portion of the sealing frame portion 142 of the metal lid 140 in plan view. The first terminal wiring portion 113a is fixed by the conductive member 170 and is electrically connected to the metal lid 140 by the conductive member 170.

  The second terminal wiring portion 113b has one end connected to the second external terminal 111b and the other end connected to the second terminal connection pad 112b. The second external terminal 111b and the second terminal connection pad 112b Are electrically connected. The third terminal wiring portion 113c has one end connected to the third external terminal 111c and the other end connected to the third terminal connection pad 112c. The third external terminal 111c and the third terminal connection pad 112c Are electrically connected.

  The fourth terminal wiring portion 113d has one end connected to the fourth external terminal 111d and the other end connected to the fourth terminal connection pad 112d. The fourth external terminal 111d and the fourth terminal connection pad 112d Are electrically connected. In addition, the fourth terminal wiring portion 113 d is partly provided along the inner peripheral edge of the sealing frame portion 142 of the metal lid 140 in plan view. For this reason, a part of the fourth terminal wiring portion 113d can be covered with the metal lid 140, so that electrostatically charged dust or the like adheres and a signal transmitted on the fourth terminal wiring portion 113d is not received. It becomes possible to reduce that it becomes stable. In the piezoelectric oscillator of this embodiment, the fourth terminal wiring portion 113d is in contact with the bonding member 150 but not the metal lid 140, and the fourth terminal wiring portion is in contact with the bonding member 150. 113 d is not electrically connected to the metal lid 140.

  The element connection pad 114 is for mounting the integrated circuit element 160. The element connection pads 114 are located on the upper surface of the substrate 110 and below the connection terminals of the integrated circuit element 160, and are fixed while being electrically connected to the connection terminals. The element connection pads 114 are electrically connected to the mounting pads 115 provided on the upper surface of the substrate 110 via the element wiring portions 116. Therefore, the connection terminal of the integrated circuit element 160 is in a state of being electrically connected to the mounting pad 115 via the element connection pad 114 and the element wiring portion 116. The element connection pad 114 includes, for example, a first element connection pad 114a and a second element connection pad 114b.

  The first element connection pad 114a is provided between the first terminal connection pad 112a and the fourth terminal connection pad 112d, and below the fifth connection terminal (not shown) of the integrated circuit element 160. positioned. The first element connection pad 114a is connected to the first element wiring portion 116a and is electrically connected to the first mounting pad 115a through the first element wiring portion 116a. The second element connection pad 114b is provided between the second terminal connection pad 112b and the third terminal connection pad 112c, and under the sixth connection terminal (not shown) of the integrated circuit element 160. positioned. The second element connection pad 114b is connected to the second element wiring portion 116b, and is electrically connected to the second mounting pad 115b via the second element wiring portion 116b.

  The mounting pad 115 is provided on the upper surface of the substrate 110 and is for mounting the vibration element 120. The mounting pad 115 includes, for example, a first mounting pad 115a and a second mounting pad 115b. The first mounting pad 115a is connected to the first element wiring portion 116a, and is electrically connected to the first element connection pad 114a via the first element wiring portion 116a. The second mounting pad 115b is connected to the second element wiring portion 116b, and is electrically connected to the second element connection pad 114b via the second element wiring portion 116b.

  The element wiring portion 116 is for electrically connecting the element connection pad 114 and the mounting pad 115, and includes, for example, a first element wiring portion 116a and a second element wiring portion 116b. The element wiring part 116 is provided so as not to overlap the terminal wiring part 113 in plan view. A portion of the first element wiring portion 116 a and the second element wiring portion 116 b are provided along the inner peripheral edge of the sealing frame portion 142 of the metal lid 140 in plan view. In the piezoelectric oscillator of the present embodiment, the first element wiring portion 116 a and the second element wiring portion 116 b are in contact with the joining member 150 that joins the substrate 110 and the metal lid body 140. Are not in contact. Accordingly, a part of the first element wiring portion 116 a and the second element wiring portion 116 b can be covered with the metal lid 140. For this reason, it is possible to reduce the instability of a signal transmitted on the first element wiring portion 116a due to adhesion of static dust or the like to the first element wiring portion 116a.

  The first element wiring portion 116a has one end connected to the first element connection pad 114a and the other end connected to the first mounting pad 115a. The first element connection pad 114a and the first mounting pad 115a are electrically connected. Connected. The second element wiring portion 116b has one end connected to the second element connection pad 114b and the other end connected to the second mounting pad 115b. The second element connection pad 114b and the second mounting pad 115b are electrically connected. Connected.

  Here, a method for manufacturing the substrate 110 is described. When the substrate 110 is made of alumina ceramic, first, a plurality of ceramic green sheets obtained by adding and mixing an appropriate organic solvent or the like to a predetermined ceramic material powder is prepared. Further, a predetermined conductive paste is applied to the surface of the ceramic green sheet or a through-hole previously provided by punching the ceramic green sheet by screen printing or the like. Thereafter, the green sheet is fired. In the case where a plurality of insulating layers are stacked on the substrate 110, green sheets are stacked and press-molded, and then fired at a high temperature. After firing, a predetermined portion of the conductor pattern, specifically, a portion that becomes the external terminal 111, the terminal connection pad 112, the terminal wiring portion 113, the element connection pad 114, the mounting pad 115 and the element wiring portion 116 It is manufactured by applying nickel plating or gold plating. The conductive paste is made of, for example, sintering resistance of a metal powder such as tungsten, molybdenum, copper, silver, or silver palladium.

  The vibration element 120 is provided with a pair of excitation electrodes 122 on the upper and lower surfaces of the piezoelectric element plate 121, and can obtain stable mechanical vibration. Therefore, the vibration element 120 plays a role of transmitting a reference signal of an electronic device or the like. An extraction electrode 123 for applying a voltage to the excitation electrode 122 is provided on the surface of the piezoelectric element plate 121 of the vibration element 120. In this embodiment, one end of the vibration element 120 connected to the mounting pad 115 is a fixed end connected to the upper surface of the substrate 110, and the other end is a cantilever having a free end spaced from the upper surface of the substrate 110. The vibration element 120 is mounted on the substrate 110 in a support structure.

  The piezoelectric element plate 121 is made of a piezoelectric material in order to perform stable mechanical vibration, for example, quartz. Here, a manufacturing method of the piezoelectric element plate 121 will be described. The piezoelectric element plate 121 is cut from the artificial crystalline lens so as to have a predetermined size at a predetermined cut angle, and is polished and processed until the piezoelectric element plate 121 has a predetermined thickness.

  The excitation electrode 122 is for applying a voltage to the piezoelectric element plate 121. The excitation electrode 122 is a pair, and is provided on the upper surface of the piezoelectric element plate 121 and the lower surface of the lower piezoelectric element 121. At this time, the excitation electrode 122 provided on the upper surface of the piezoelectric element plate 121 and the excitation electrode 122 provided on the lower surface of the piezoelectric element plate 121 face each other. The excitation electrode 122 is formed by depositing a metal film on a predetermined position of the piezoelectric element plate 121 by a photolithography technique, a vapor deposition technique, or a sputtering technique.

  The extraction electrode 123 is for applying a voltage to the excitation electrode 122 from the outside of the vibration element 120. The extraction electrode 123 is provided so that one end is connected to the excitation electrode 122 and the other end is located on the upper surface of the piezoelectric element plate 121 or the edge of the lower surface of the piezoelectric element plate 121.

  Here, the operation of the vibration element 120 will be described. When a voltage is applied to the extraction electrode 123 from the outside, the vibration element 120 applies a voltage to the excitation electrode 122 to which the other end of the extraction electrode 123 is connected. As a result, different charges are accumulated in the pair of excitation electrodes 122, and a part of the piezoelectric element plate 121 sandwiched between the excitation electrodes 122 is distorted and deformed due to the inverse piezoelectric effect. As a result, since the piezoelectric element plate 121 tries to return to its original shape, electric charges opposite to the electric field initially accumulated in the excitation electrode 122 are accumulated due to the piezoelectric effect. That is, when a voltage is applied to the excitation electrode 122, the vibration element 120 vibrates part of the piezoelectric element plate 121 sandwiched between the excitation electrodes 122 due to the piezoelectric effect and the inverse piezoelectric effect. Therefore, when an alternating voltage is applied to the extraction electrode 123, the vibration element 120 alternately accumulates different charges on the excitation electrode 122, and can vibrate the piezoelectric element plate 121.

  A mounting method for mounting the vibration element 120 on the upper surface of the substrate 110 will be described. First, the conductive adhesive 130 is applied to the upper surface of the mounting pad 115 by, for example, a dispenser. Thereafter, the vibration element 120 is conveyed onto the conductive adhesive 130 and placed on the conductive adhesive 130 so that the extraction electrode 123 and the conductive adhesive 130 are in contact with each other. In this state, the conductive adhesive 130 is cured by heating. Accordingly, the vibration element 120 is mounted on the upper surface of the substrate 110 in a state where the mounting pad 115 and the extraction electrode 123 are fixed to each other while being electrically connected by the conductive adhesive 130.

  The conductive adhesive 130 contains conductive powder as a conductive filler in a binder such as a silicone resin. Examples of the conductive powder include aluminum, molybdenum, tungsten, platinum, palladium, silver, titanium, The thing containing either nickel or nickel iron, or these combination is used. Moreover, as a binder, a silicone resin, an epoxy resin, a polyimide resin, or a bismaleimide resin is used, for example.

  The metal lid 140 is bonded to the upper surface of the substrate 110 by the bonding member 150 and hermetically seals the vibration element 120 mounted on the upper surface of the substrate 110. The metal lid 140 is composed of a sealing base 141 and a sealing frame 142.

  The sealing base 141 is a rectangular flat plate, and the size of the main surface is larger than the upper surface of the vibration element 120 and smaller than the upper surface of the substrate 110. A recess space is formed on the lower surface of the sealing base 141.

The sealing frame part 142 is comprised from the frame part 142a and the collar part 142b. The frame portion 142 a is for forming a recessed space on the lower surface of the sealing base portion 141, and is provided along the outer edge of the lower surface of the sealing base portion 141. In the recessed space, the vibration element 120 mounted on the upper surface of the substrate 110 is accommodated. The collar 142b is for securing an area for joining the metal lid 140 and the substrate 110 and increasing the joining strength.
The collar portion 142b is annular along the outer peripheral surface of the frame portion 142a and extends to the outer peripheral side of the frame portion 142a.

  The sealing base 141 and the sealing frame 142 are made of, for example, an alloy containing at least one of iron, nickel, and cobalt, and are integrally formed. The metal lid 140 is for hermetically sealing a recessed space in a vacuum state or a recessed space filled with nitrogen gas or the like. Specifically, the metal lid 140 is formed in a predetermined atmosphere between the lower surface of the sealing frame portion 142 and the upper surface of the substrate 110, specifically, between the lower surface of the frame portion 142a and the upper surface of the substrate 110. Heat is applied to the bonding member 150 provided between the gap and the lower surface of the flange 142b and the upper surface of the substrate 110, the bonding member 150 is melted, and the lower surface of the metal lid 140 and the upper surface of the substrate 110 are melt bonded. Is done.

  Here, a method for producing the metal lid 140 will be described. For the production of the metal lid 140, conventionally known press working is used. First, a rectangular flat plate is prepared, and a pair of molds having a convex portion and a concave portion having the same shape as the concave space of the metal lid 140 are pressed between the flat plate, the sealing base 141 and the sealing A frame portion 142 is provided to form a recessed space. As described above, the metal lid 140 is produced by plastic processing of a flat plate using press working.

  The bonding member 150 is provided between the lower surface of the sealing frame portion 142 of the metal lid 140 and the upper surface of the substrate 110, and is for bonding the metal lid 140 and the substrate 110. The bonding member 150 is made of an insulating material. For example, in the case of glass, the bonding member 150 is a glass that melts at 300 to 400 degrees Celsius. For example, low melting glass containing vanadium or lead oxide Consists of glass. The composition of the oxide-based lead glass is composed of lead oxide, lead fluoride, titanium dioxide, niobium oxide, bismuth oxide, boron oxide, zinc oxide, ferric oxide, copper oxide, and calcium oxide. Accordingly, the first element wiring portion 116 a, the second element wiring portion 116 b and the fourth terminal wiring portion 113 d located under the bonding member 150 are electrically connected via the bonding member 150 or the metal lid 140. You can avoid it.

  Next, a joining method for joining the metal lid 140 and the substrate 110 using the joining member 150 will be described. The glass used as the raw material of the joining member 150 is in a paste form to which a binder solvent is added. After being melted, the glass is solidified and bonded to another member. The joining member 150 is provided by, for example, applying glass frit paste to the lower surface of the sealing frame portion 142 by screen printing and drying.

  The integrated circuit element 160 has a function of an oscillation circuit, and is for oscillating the vibration element 120. The integrated circuit element 160 is mounted on the upper surface of the substrate 110 so as to be adjacent to the vibration element 120. A plurality of connection terminals are provided on the lower surface of the integrated circuit element 160. The connection terminal includes, for example, a first connection terminal, a second connection terminal, a third connection terminal, a fourth connection terminal, a fifth connection terminal, and a sixth connection terminal.

  For example, the first connection terminal is a terminal to which a ground potential serving as a reference potential is input when the integrated circuit element 160 is driven. The first connection terminal is located on the first terminal connection pad 112a provided on the upper surface of the substrate 110, and is electrically connected to the first terminal connection pad 112a by a metal material such as solder. Yes. Therefore, the first connection terminal is electrically connected to the first external terminal 111a via the metal material, the first terminal connection pad 112a, and the first terminal wiring portion 113a. That is, when the first external terminal 111a is mounted on a motherboard such as an electronic device, the first connection is established by being fixedly connected to a mounting pad connected to a ground potential that is a reference potential on the motherboard of the electronic device or the like. The terminal has the same potential as the ground potential.

  For example, the second connection terminal is a terminal to which a power supply voltage for driving the integrated circuit element 160 is input. The second connection terminal is located on the second terminal connection pad 112b provided on the upper surface of the substrate 110, and is electrically connected to the second terminal connection pad 112b by a metal material such as solder. Yes. Therefore, the second connection terminal is electrically connected to the second external terminal 111b via the metal material, the second terminal connection pad 112b, and the second terminal wiring portion 113b. That is, when the second external terminal 111b is mounted on a motherboard such as an electronic device, the power supply voltage is input from the mounting pad provided on the motherboard, whereby the power supply voltage is input to the second connection terminal, and the integrated circuit The element 160 can be driven.

  The third connection terminal is, for example, a terminal that outputs a predetermined frequency as a voltage signal from the integrated circuit element 160. The third connection terminal is located on the third terminal connection pad 112c provided on the upper surface of the substrate 110, and is electrically connected to the third terminal connection pad 112c by a metal material such as solder. Yes. Accordingly, the third connection terminal is electrically connected to the third external terminal 111c via the metal material, the third terminal connection pad 112c, and the third terminal wiring portion 113c. That is, a predetermined frequency is output as a signal voltage from the third external terminal 111c.

  For example, the fourth connection terminal is a terminal to which an adjustment voltage for adjusting a signal output from the third connection terminal is input. The fourth connection terminal is located on the fourth terminal connection pad 112d provided on the upper surface of the substrate 110, and is electrically connected to the fourth terminal connection pad 112d by a metal material such as solder. Yes. Accordingly, the fourth connection terminal is electrically connected to the fourth external terminal 111d through the metal material, the fourth terminal connection pad 112d, and the fourth terminal wiring portion 113d. That is, when the fourth external terminal 111d is mounted on a motherboard such as an electronic device, the adjustment voltage is input from the mounting pad provided on the motherboard, so that the adjustment voltage is input to the fourth connection terminal. The signal voltage output from the third connection terminal of the integrated circuit element 160 can be adjusted.

  The fifth connection terminal is a terminal to which a signal from the vibration element 120 is input / output, for example. The fifth connection terminal is located on the first element connection pad 114a provided on the upper surface of the substrate 110, and is electrically connected to the first element connection pad 114a by a metal material such as solder. . Accordingly, the fifth connection terminal is electrically connected to the vibration element 120 by the metal material, the first element connection pad 114a, the first element wiring portion 116a, the first mounting pad 115a, and the conductive adhesive 130. .

  The sixth connection terminal is a terminal to which a signal from the vibration element 120 is input / output, for example. The sixth connection terminal is located on the second element connection pad 114b provided on the upper surface of the substrate 110, and is electrically connected to the second element connection pad 114b by a metal material such as solder. . Accordingly, the sixth connection terminal is electrically connected to the vibration element 120 by the metal material, the second element connection pad 114b, the second element wiring portion 116b, the second mounting pad 115b, and the conductive adhesive 130. .

  The conductive member 170 is made of a conductive material and electrically connects one of the terminal wiring portions 113 and the metal lid 140. The conductive member 170 is bonded to a part of the first terminal wiring portion 113a that is connected and fixed to a mounting pad connected to a ground potential that is a reference potential on a motherboard of an electronic device or the like, and has a metal lid. It is bonded to the outer peripheral surface of the sealing frame portion 142 of the body 140. Therefore, the metal lid 140 is in a state of being electrically connected to the first external terminal 111a via the conductive member 170 and the first terminal wiring portion 113a, and the first external terminal 111a is connected to the ground potential. The metal lid 140 can be set to the same potential as the ground potential by being fixedly connected to the mounting pad.

  For the conductive member 170, for example, a conductive adhesive is used. The conductive member 170 includes, for example, conductive powder as a conductive filler in a binder such as silicone resin, and examples of the conductive powder include aluminum, molybdenum, tungsten, platinum, palladium, silver, titanium, The thing containing either nickel or nickel iron, or these combination is used. Moreover, as a binder, a silicone resin, an epoxy resin, a polyimide resin, or a bismaleimide resin is used, for example. The conductive member 170 is applied by a dispenser to a position where it comes into contact with the first terminal wiring portion 113a while being in contact with the outer peripheral surface of the sealing frame portion 142 of the metal lid 140, and is heated and cured in that state. Is formed.

  In the piezoelectric oscillator in this embodiment, the terminal wiring portion 113 is provided on the substrate 110. In the terminal wiring portion 113, an external terminal 111 provided on the lower surface of the substrate 110 and a terminal connection pad 112 provided on the upper surface of the substrate 110 are electrically connected. In the piezoelectric oscillator according to this embodiment, the metal lid 140 and the predetermined one terminal wiring portion 113, specifically, the first terminal wiring portion 113 a are electrically connected by the conductive member 170. Yes. That is, in the piezoelectric oscillator according to the present embodiment, the first external terminal 111a to which the first terminal wiring portion 113a is connected is electrically connected to the metal lid 140 via the first terminal wiring portion 113a and the conductive member 170. Can be connected. Therefore, in the piezoelectric oscillator according to this embodiment, when mounting on a motherboard such as an electronic device, the first external terminal 111a is connected to a mounting pad connected to a ground potential that is a reference potential on the motherboard of the electronic device. Thus, the metal lid 140 bonded to the substrate 110 by the bonding member 150 that is an insulating material can be set to the same potential as the ground potential via the first terminal wiring portion 113a and the conductive member 170. Further, in the piezoelectric oscillator of this embodiment, the vibration element 120 is mounted on the mounting pad 115 provided on the upper surface of the substrate 110, the substrate 110 and the metal lid 140 are bonded by the bonding member 150, and the vibration element 120 is bonded to the substrate. The space surrounded by 110 and the metal lid 140 is hermetically sealed. For this reason, in such a piezoelectric oscillator, the vibration element 120 can be brought close to the state surrounded by the electrostatic shield by setting the metal lid 140 to the same potential as the ground potential. That is, when the piezoelectric oscillator of this embodiment is mounted on a motherboard such as an electronic device, the external terminal 111 to which the terminal wiring portion 113 to which the conductive member 170 is fixed is connected, specifically, the first One external terminal 111a is connected and fixed to a mounting pad connected to the ground potential, thereby stray capacitance generated between the excitation electrode 122 of the vibration element 120 and the metal lid 140 or the excitation electrode of the vibration element 120. The stray capacitance generated between 122 and the outside of the piezoelectric oscillator can be reduced as compared with the conventional piezoelectric oscillator, the frequency fluctuation due to the stray capacitance can be suppressed, and the output signal can be stabilized. .

  Further, in the piezoelectric oscillator according to the present embodiment, a part of the element wiring portion 116 is provided along the inner edge of the sealing frame portion 142 in plan view. For this reason, a part of the element wiring part 116 is housed in the recessed space of the metal lid 140, and the signal transmitted on the element wiring part 116 due to dust or the like adhering to the element wiring part 116. Can be reduced, and it is possible to prevent the signals output from the integrated circuit element 160 and the piezoelectric oscillator of this embodiment from becoming unstable.

  In addition, since a part of the element wiring portion 116 is housed in the recessed space of the metal lid 140, the metal lid 140 has the same potential as the ground potential on the motherboard of the electronic device or the like. In this case, a part of the element wiring part 116 can be brought close to the state surrounded by the electrostatic shield. Therefore, in the piezoelectric oscillator of the present embodiment, it is possible to reduce the instability of the signal transmitted on the element wiring portion 116 being coupled with the signal outside the piezoelectric oscillator, and the integrated circuit element 160 and the present embodiment. It is possible to prevent the signal output from the piezoelectric oscillator of the form from becoming unstable.

  In the piezoelectric oscillator of this embodiment, a part of one predetermined terminal wiring portion 113 is provided along the outer edge portion of the sealing frame portion 142. Specifically, in the piezoelectric oscillator of this embodiment, a part of the first terminal wiring portion 113a is provided along the outer edge portion of the flange portion 142b of the sealing frame portion 142 in plan view. In the piezoelectric oscillator of this embodiment, the first terminal wiring portion 113a and the sealing frame portion 142 of the metal lid 140 are bonded and electrically connected by the conductive member 170. Therefore, in the piezoelectric oscillator according to the present embodiment, the interval between the sealing frame portion 142 and the first terminal wiring portion 113a can be shortened, so that the first terminal wiring portion 113a and the sealing frame portion 142 are in contact with each other. On the other hand, the conductive member 170 can be easily provided so that the other terminal wiring portions 113b, 113c and 113d and the element wiring portion 116 are not attached and the other wiring portion and the metal lid 140 are not short-circuited. It becomes possible, and productivity can be improved.

  In the piezoelectric oscillator of this embodiment, the terminal wiring portion 113 and the element wiring portion 116 are provided on the surface of the substrate 110. Therefore, in the piezoelectric oscillator of this embodiment, the substrate 110 made of a single insulating layer can be used, and the substrate 110 can be made thinner than the conventional one. Therefore, the piezoelectric oscillator of this embodiment can be made thinner than the conventional one.

(Modification)
Hereinafter, a piezoelectric oscillator according to a modification of the present embodiment will be described. Note that, in the piezoelectric oscillator according to the modification of the present embodiment, the same parts as those of the above-described piezoelectric oscillator are denoted by the same reference numerals, and description thereof will be omitted as appropriate. In the piezoelectric oscillator according to the present embodiment, as shown in FIG. 4, a part of the terminal wiring part 213 and a part of the element wiring part 216 intersect each other with an insulating layer 280 provided therebetween. It differs from the embodiment in that.

  A terminal wiring portion 213 that electrically connects the external terminal 211 and the terminal connection pad 212 electrically connects the element mounting pad 214 and the mounting pad 215 to the substrate 210 in plan view. There is an intersecting portion (not shown) that intersects with the element wiring portion 216. At this time, an insulating layer 280 is provided between the intersecting terminal wiring portion 213 and the element wiring portion 216.

  The external terminals 211 provided on the lower surface of the substrate 210 include a first external terminal 211a, a second external terminal 211b, a third external terminal 211c, and a fourth external terminal 211d. At this time, one external terminal 211 is provided at each of the four corners of the lower surface of the substrate 210. The first external terminal 211a is, for example, a ground terminal that has the same potential as the ground potential.

  The terminal connection pad 212 is connected to the terminal wiring portion 213 and is electrically connected to the external terminal 211 provided on the lower surface of the substrate 210. The terminal connection pads 212 include, for example, a first terminal connection pad 212a, a second terminal connection pad 212b, a third terminal connection pad 212c, and a fourth terminal connection pad 212d.

  The terminal wiring portion 213 is provided on the substrate 210, and electrically connects the external terminal 211 provided on the lower surface of the substrate 210 and the terminal connection pad 212 provided on the upper surface of the substrate 210. belongs to. The terminal wiring portion 213 includes, for example, a first terminal wiring portion 213a, a second terminal wiring portion 213b, a third terminal wiring portion 213c, and a fourth terminal wiring portion 213d.

  The first terminal wiring portion 213a has one end connected to the first external terminal 211a and the other end connected to the first terminal connection pad 212a. The first external terminal 211a and the first terminal connection pad 212a Are electrically connected. The first terminal wiring portion 213a is provided along the outer edge portion of the sealing frame portion 142 of the metal lid 140 in plan view. Further, the first terminal wiring portion 213a is fixed by a conductive member, and is electrically connected to the metal lid 140 by the conductive member. The first terminal wiring portion 213a is provided with an insulating layer 280 below the first terminal wiring portion 213a. The first element wiring portion 216a and the fourth terminal wiring portion 213d are provided with the insulating layer 280. There is a part that intersects with At this time, the first terminal wiring portion 213a and the first element wiring portion 216a, and the first terminal wiring portion 213a and the fourth terminal wiring portion 213d are insulated by the insulating layer 280. .

  The second terminal wiring portion 213b has one end connected to the second external terminal 211b and the other end connected to the second terminal connection pad 212b. The second external terminal 211b and the second terminal connection pad 212b Are electrically connected. In addition, an insulating layer 280 is provided under the second terminal wiring portion 213b, and there is a portion where the second element wiring portion 216b intersects with the insulating layer 280 interposed therebetween. At this time, the second terminal wiring portion 213b and the second element wiring portion 216b are insulated by the insulating layer 280.

  The third terminal wiring portion 213c has one end connected to the third external terminal 211c and the other end connected to the third terminal connection pad 212c. The third external terminal 211c and the third terminal connection pad 212c Are electrically connected.

  The fourth terminal wiring part 213d has one end connected to the fourth external terminal 211d and the other end connected to the fourth terminal connection pad 212d. The fourth external terminal 211d and the fourth terminal connection pad 212d Are electrically connected. Further, the fourth terminal wiring portion 213d is partly provided along the inner peripheral edge of the sealing frame portion 142 of the metal lid 140 in plan view. For this reason, part of the fourth terminal wiring part 213d can be covered with the metal lid 140, so that electrostatically charged dust or the like adheres to it, and the signal transmitted on the fourth terminal wiring part 213d is not received. It becomes possible to reduce that it becomes stable. In the piezoelectric oscillator of the present embodiment, the fourth terminal wiring portion 213d is in contact with the bonding member but not the metal lid 140, and the fourth terminal wiring portion 213d. Is not electrically connected to the metal lid 140. Further, the fourth terminal wiring portion 213d has a portion intersecting with the first terminal wiring portion 213a in plan view. In the intersecting portion, the insulating layer 280 is provided on the upper surface of the fourth terminal wiring portion 213d, and further, the first terminal wiring portion 213a is provided on the upper surface of the insulating layer 280. Therefore, in the portion where the fourth terminal wiring portion 213d and the first terminal wiring portion 213a intersect, the fourth terminal wiring portion 213d and the first terminal wiring portion 213a are insulated by the insulating layer 280. It has become.

  The element wiring portion 216 includes, for example, a first element wiring portion 216a and a second element wiring portion 216b. Further, the element wiring portion 216 intersects with the terminal wiring portion 213 in plan view with the insulating layer 280 provided therebetween. The first element wiring part 216 a and the second element wiring part 216 b are partly provided along the inner periphery of the sealing frame part 142 of the metal lid 140 in plan view.

  The insulating layer 280 is a portion where the terminal wiring portion 213 and the element wiring portion 216 intersect, and the terminal wiring portion 213 intersects, and between the terminal wiring portion 213 and the element wiring portion 216, And it is for preventing being electrically connected between the wiring parts 213 for terminals. Specifically, the insulating layer 280 is an upper surface of the first element wiring portion 216a, the second element wiring portion 216b, and the fourth terminal wiring portion 213d, and includes the first element wiring portion 216a and the first terminal. The portion where the wiring portion 213a intersects, the portion where the second element wiring portion 216b intersects the second terminal wiring portion 213b, and the first terminal wiring portion 213a and the fourth terminal wiring It is provided at a portion where the portion 213d intersects.

  The insulating layer 280 is made of, for example, an insulating material, and is made of, for example, glass (glass coat layer). The glass contains, for example, borosilicate glass as a main component. Further, the insulating layer 280 does not melt even when heat is applied when the substrate 210 and the metal lid 140 are joined by the joining member.

  Here, a method for manufacturing the substrate 210 is described. When the substrate 210 is made of alumina ceramic, first, a plurality of ceramic green sheets obtained by adding and mixing an appropriate organic solvent or the like to a predetermined ceramic material powder are prepared, Specifically, the external terminal 211, the terminal connection pad 212, the element connection pad 214, the mounting pad 215, the element wiring part 216, the second terminal wiring part 213b, the third terminal wiring part 213c, and the fourth terminal use A conductive paste is applied to the portion to be the wiring portion 213d and baked. Further, after that, molten glass is applied and solidified on the portion to be the insulating layer 280 to provide the insulating layer 280, and the conductive paste is applied to the portion to be the first terminal wiring portion 213a and baked. In this way, the substrate 210 is formed.

  In the piezoelectric oscillator according to the modified example of the present embodiment, there is an intersection where the terminal wiring portion 213 and the element wiring portion 216 intersect each other, and the terminal wiring portion 213 and the element wiring portion 216 at the intersection are formed. Since the insulating layer 280 is provided between them, complicated wiring is not required, and the area of the substrate 210 can be reduced and the size can be reduced.

  In addition, although the case where a joining member consists of glass is demonstrated here, even if it joins the lower surface of a metal cover body and the upper surface of a board | substrate, and is an insulating material, even if it is an epoxy resin or a polyimide resin, for example Good.

  Further, although the case where the conductive member is made of a conductive adhesive is described, if the metal lid and the predetermined one terminal wiring portion can be electrically connected, for example, a metal material such as solder It may be. At this time, the conductive member is formed by applying and solidifying the metal material melted by heat so as to contact the side surface of the sealing frame portion of the metal lid and the predetermined one terminal wiring portion. The

  Although not particularly shown in the piezoelectric oscillator of this embodiment, an insulating resin may be provided on the substrate so as to cover the integrated circuit element and the metal lid.

110 ... Board 111, 211 ... External terminal 112, 212 ... Terminal connection pad 113, 213 ... Terminal wiring part 114, 214 ... Element connection pad 115, 215 ... Mounted Pads 116, 216 ... Element wiring portion 120 ... Vibration element 121 ... Piezoelectric base plate 122 ... Excitation electrode 123 ... Extraction electrode 130 ... Conductive adhesive 140 ... Metal lid Body 141... Sealing base portion 142... Sealing frame portion 142 a... Frame portion 142 b.

Claims (4)

A substrate,
A plurality of external terminals provided on the lower surface of the substrate;
A plurality of terminal connection pads provided on the upper surface of the substrate;
A terminal wiring portion provided on the substrate, having one end connected to the external terminal and the other end connected to the terminal connection pad;
A pair of element connection pads provided on the upper surface of the substrate and arranged side by side with the terminal connection pads;
A pair of mounting pads provided on the upper surface of the substrate;
An element wiring portion provided on the substrate, having one end connected to the element connection pad and the other end connected to the mounting pad;
A vibration element connected and fixed to the mounting pad; and
An integrated circuit element mounted and fixedly connected to the terminal connection pad and the element connection pad;
A metal lid composed of a sealing base and a sealing frame provided along the outer edge of the lower surface of the sealing base;
A bonding member provided between the upper surface of the substrate and the lower surface of the sealing frame portion;
A conductive member fixed to the metal lid and one of the terminal wiring portions;
A piezoelectric oscillator comprising: The piezoelectric oscillator according to claim 1,
A part of the element wiring portion is provided along an inner edge of the sealing frame portion. The piezoelectric oscillator according to claim 1 or 2,
A part of one predetermined terminal wiring part is provided along the outer edge part of the sealing frame part, The piezoelectric oscillator characterized by the above-mentioned. A piezoelectric oscillator according to claim 1, claim 2 or claim 3, wherein
There is an intersection where the terminal wiring portion and the element wiring portion intersect,
A piezoelectric oscillator, wherein an insulating layer is provided between the terminal wiring portion and the element wiring portion at the intersection.

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