JP2013098628A - Surface mounting crystal oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constitute an inexpensive surface mounting crystal oscillator by laminating and bonding a package (crystal resonator) into which a crystal piece is hermetically enclosed to an IC mounting substrate without using a package with an H-type cross section formed by burning and laminating an expensive ceramic plate.SOLUTION: In the surface mounting crystal oscillator, an IC mounting substrate 7 to which an IC chip 4 is bonded and a crystal resonator 2 composed of a hermetically enclosed crystal piece 3 and crystal packages 2a, 2b are laminated and bonded each other, and a crystal resonator connection terminal 9a of the IC mounting substrate 7 and a terminal 9b of the crystal resonator are mutually connected by a conductor 6a, e.g. a coreless solder ball or an anisotropic conductive sheet.

Description

  The present invention relates to a surface mount crystal oscillator, and in particular, a crystal resonator and an IC mount substrate are connected by a conductor such as a solder ball using the height of an IC chip mounted on the IC mount substrate as a positioning reference. The present invention relates to a temperature compensated crystal oscillator (TCXO).

  As a representative example of a crystal device in which a crystal resonator and an IC chip are integrated, a crystal oscillator for surface mounting in which a crystal resonator and an IC chip in which an oscillation circuit used for the crystal resonator is integrated are integrated. There is.

  Since the surface-mount crystal oscillator is small and lightweight, it is widely used as a reference source for frequency and time, particularly in portable electronic devices such as mobile phones.

  As a typical example of such a surface-mount crystal oscillator, as shown in FIG. 16, ceramic plates 2b and 2c having openings formed on both main surfaces of the ceramic plate 2a are fired and laminated, respectively, to form a recess 12a. , 12b to form a ceramic package 2 having an H-shaped cross section, and a crystal piece 3 is bonded to one of the recesses 12a by a conductive adhesive 3a to a crystal holding terminal 3b, and then a lid is connected via a metal ring 13. 8 is hermetically sealed, and the IC chip 4 is fixed to the IC mounting substrate 7 by the IC mounting bump 5 and the anisotropic conductive resin 14 in the other concave portion 12b, and bonded to the crystal resonator by the bonding terminals 15a and 15b. After that, an H-type surface-mount crystal oscillator is stored. Then, a crystal oscillator is mounted on a mounting substrate (not shown) by an oscillator mounting terminal (Patent Document 1).

  In particular, the temperature-compensated crystal oscillator (TCXO) has recently been miniaturized, and oscillators with outer dimensions of 2.0 mm x 1.6 mm x 0.8 mm have been produced. Currently, development of a TCXO having a size of 1.6 mm × 1.2 mm × 0.7 mm is underway. However, as TCXO becomes smaller, its manufacture becomes difficult, but its price tends to be lowered recently. Therefore, realization of a compact TCXO that is easy to manufacture and inexpensive is eagerly desired.

JP 2009-105628 A JP 2004-180012 A

  However, in this type of conventional surface-mount crystal oscillator, a plurality of ceramic plates (for example, three) are fired and stacked to form a package with an H-shaped cross section, and a crystal piece and an IC chip are made of resin in each recess. Although it was sealed after being covered, the ceramic package is extremely expensive, so the cost of the crystal oscillator becomes high, and when the IC chip is covered with resin, the resin does not protrude from the recess of the package Since it is very difficult to inject it, the productivity is extremely low.

  Also, in the piezoelectric oscillator, a solder ball is used as a conductor for electrically connecting the external terminal and the connection terminal, a position restricting means is provided on the oscillation circuit board, and the solder ball, the connection terminal, and the external terminal are horizontally oriented However, the height of the IC chip is not used as a positioning reference (Patent Document 2).

  In order to solve the above-described problems, a surface-mount crystal oscillator according to the present invention includes an IC mounting substrate or a crystal connection substrate to which an IC chip is bonded, a crystal resonator including a hermetically sealed crystal piece and a crystal package, And a crystal resonator connection terminal of the IC mounting substrate or the crystal connection substrate and a terminal of the crystal resonator are connected by a conductor.

  In the crystal oscillator for surface mounting according to the present invention, the conductor is composed of a coreless solder ball.

  Here, the coreless solder ball has a diameter of 50 μm to 300 μm.

  Furthermore, the conductor is made of an anisotropic conductive sheet.

  Further, the anisotropic conductive sheet is formed in a ring shape in a plan view, or the anisotropic conductive sheet is formed in a tape shape in a plan view.

  Still further, the anisotropic conductive sheet has adhesiveness, or the anisotropic conductive sheet has no adhesiveness.

  The present invention is characterized in that the IC chip is bonded to the IC mounting substrate or the crystal resonator connecting substrate by a gold bump, or is bonded to the IC mounting substrate by a solder bump.

  Further, a joint between the IC chip and the IC mounting substrate or the crystal resonator connecting substrate is protected with an insulating epoxy adhesive, and the IC mounting substrate or the crystal resonator connecting substrate and the IC chip are protected. It is characterized by filling an insulating epoxy adhesive in between.

  Further, the present invention is characterized in that a GND layer is embedded in the IC mounting substrate (inner layer).

  Further, the present invention is characterized in that a GND layer is embedded in the IC mounting substrate so as to correspond to the bottom of the wiring formed on the IC mounting substrate.

  Furthermore, a GND layer is embedded in the IC mounting substrate, and the maximum outer dimension of the GND layer is larger than the outer dimensions of the crystal connection terminal and the crystal connection terminal and the wiring pattern of the IC chip. It is formed.

  The surface-mount crystal oscillator is a temperature-compensated crystal oscillator.

  In the present invention, the IC chip includes a temperature sensor circuit that generates a temperature compensation voltage, a temperature compensation circuit that generates a temperature compensation voltage using an output of the temperature sensor circuit, and a non-volatile for determining a temperature compensation amount A memory, a crystal oscillation circuit, and a buffer circuit for outputting an analog signal output from the crystal oscillation circuit are stored.

  Since the crystal resonator connection terminal of the IC mounting substrate or crystal resonator connecting substrate and the crystal resonator terminal are connected by a conductor such as a coreless solder ball or anisotropic conductive sheet, the IC mounting substrate or crystal vibration The distance between the connection board and the crystal unit after the connection can be made constant, and the surface mount crystal unit can be manufactured accurately, inexpensively and with high productivity.

1 shows a temperature-compensated crystal oscillator, which is an embodiment of a surface-mount crystal oscillator according to the present invention, in which a crystal resonator connection terminal of an IC mounting substrate and a crystal resonator terminal are connected by a solder ball without a core. An example is shown, (a) is a top view seen from the top, (b) shows the longitudinal section, (c) shows the longitudinal section of the example which formed the GND layer in the IC mounting substrate. Show. The bottom view of the temperature compensation type | mold crystal oscillator of this invention shown in FIG. 1 is shown. FIG. 2 is a plan view showing a state in which an IC chip is mounted on an upper surface of an IC mounting substrate in the temperature compensated crystal oscillator of the present invention shown in FIG. 1. It is a partial expanded sectional view of the part shown by A arrow in FIG. FIG. 2 is a block diagram of the temperature compensated crystal oscillator according to the first embodiment of the present invention shown in FIG. 1. 1 is a longitudinal sectional view of a temperature-compensated crystal oscillator that is a second embodiment of a surface-mount crystal oscillator according to the present invention, and an anisotropic conductive sheet is used to connect a crystal resonator connection terminal and a crystal resonator terminal of an IC mounting substrate. The connected embodiment is shown. FIG. 7 shows a bottom view of the second embodiment of the temperature compensated crystal oscillator of the present invention shown in FIG. 6. The top view which looked at the anisotropic conductive sheet used for the temperature compensation type | mold crystal oscillator of this invention shown in FIG. 6 from the top is shown. FIG. 7 is a plan view showing a state in which an IC chip is mounted on an upper surface of an IC mounting substrate in the temperature compensated crystal oscillator of the present invention shown in FIG. 6. FIG. 6 is a longitudinal sectional view of a temperature-compensated crystal oscillator according to a third embodiment of the present invention, in which the crystal resonator connection terminal of the IC mounting substrate and the crystal resonator terminal are connected by an anisotropic conductive sheet having adhesive force. The form is shown. FIG. 11 shows a bottom view of the third embodiment of the temperature compensated crystal oscillator of the present invention shown in FIG. 10. The top view which looked at the anisotropic conductive sheet with the adhesive force used for the temperature compensation type | mold crystal oscillator of this invention shown in FIG. 10 from the top is shown. FIG. 10 is a plan view showing a state in which an IC chip is mounted on an IC mounting substrate in the temperature compensated crystal oscillator of the present invention shown in FIG. 10, and FIG. b) is a plan view after the IC chip is mounted on the IC terminal. FIG. 9 is a longitudinal sectional view of a temperature-compensated crystal oscillator according to a fourth embodiment of the present invention, in which the crystal resonator connection terminal of the IC mounting substrate and the crystal resonator terminal are connected by an anisotropic conductive sheet having no adhesive force. The form is shown. FIG. 15 is a bottom view of the temperature-compensated crystal oscillator according to the fourth embodiment of the present invention shown in FIG. 14. The longitudinal cross-sectional view of the surface mount-type crystal oscillator which has a package of the H-shaped cross section of a prior art example is shown.

  Embodiments of a surface-mount crystal oscillator according to the present invention will be described below with reference to the accompanying drawings.

Example 1
In Example 1, a coreless solder ball is used as a conductor connecting an IC mounting substrate and a crystal resonator.

  As shown in FIGS. 1A, 1B, and 4, the temperature-compensated crystal oscillator according to the first embodiment of the surface-mount crystal oscillator of the present invention is an IC mounting substrate 7 made of a ceramic, a crystal plate, or a glass plate. IC mounting bumps (solder or gold bumps) 5 on the upper surface main surface of the IC chip 4 or IC chip 4 mounted by flip chip bonding, and a ceramic or crystal plate or glass plate on the upper surface main surface of the IC chip 4 A crystal package 2 (referred to as a crystal resonator) composed of 2a and 2b and having a crystal piece 3 bonded and held to a crystal holding terminal 3b by a conductive adhesive 3a is bonded to the upper portion of the crystal package 2 A lid 8 made of Kovar or a quartz plate is hermetically sealed and sealed by seam welding or the like.

  Insulation between the lower surface main surface of the IC chip 4 mounted on the upper surface main surface of the IC mounting substrate 7 by IC chip bumps 5 or flip chip bonding and the upper surface main surface to prevent cracking of terminals due to thermal stress. Alternatively, the bonding portion 4a of the IC chip 4 may be bonded to the crystal package 2 with an insulating epoxy resin.

  Since the solder ball 6a has no core and is deformed when heated and pressed from above, the vertical height h of the IC chip 4 joined to the IC mounting substrate 7 via the IC mounting bumps 5 is set as a positioning reference position. The crystal resonator connection terminal 9a of the IC mounting substrate 7 and the terminal 9b of the crystal resonator 2 provided on the bottom surface of the crystal resonator 2 are used as a solder ball 6a without a core (solid with no core portion inside). A (conductor) is interposed, and the solder ball 6a is heated and melted to be mechanically and electrically connected to the crystal resonator 2 and the IC mounting substrate 7. Here, after the connection, in order to prevent intrusion of dust, the periphery of the coreless solder ball 6a may be resin-sealed.

  Here, the coreless solder ball 6a may be placed directly on the crystal resonator connection terminal 9a provided on the upper surface of the IC mounting substrate 7. However, after solder is printed on the IC mounting substrate 7 in advance, the solder ball 6a is melted. Further, the coreless solder ball 6a may be formed at an individual piece or wafer level. Alternatively, solder may be printed on the terminals 9b of the crystal resonator 2 in advance, and then melted to form the coreless solder balls 6a at a piece or wafer level.

  In particular, in the first embodiment, by using a coreless solder ball (for example, lead-free solder ball) for connection between a crystal resonator and an IC mounting substrate, for example, compared to a cored ball in which a SnAg plating is applied to a copper core ball. Solder balls can be obtained as inexpensive conductors.

  Here, in order to reduce the height of the crystal oscillator as much as possible, the diameter of the solder ball 6a used for connection is set in the range of 50 μm to 300 μm.

  Further, on the lower surface (bottom surface) main surface of the IC mounting substrate 7, as shown in FIG. 2, an oscillator mounting terminal 30 (external terminal) (VDD: for mounting an oscillator on a customer mounting substrate (not shown)). A power supply terminal, GND: ground terminal, OUT: oscillation output terminal, AFC: automatic frequency control terminal) are provided. In particular, these oscillator mounting terminals 30 are connected to the electrode pads 5a of the IC mounting bumps 5 by through electrodes 30a formed in via holes penetrating the IC mounting substrate 7, as shown in detail in FIG.

  Further, as described above, the crystal mounting terminals (GND, X1, X2) are connected to the main surface of the upper surface of the IC mounting substrate 7 in order to connect the crystal resonator 2 and the IC mounting substrate 7 using the solder balls 6a. Terminals 9 a are provided, and these crystal connection terminals 9 a are connected to electrode pads 5 a for mounting the IC chip 4 on the IC mounting substrate 7.

  Further, as shown in FIG. 3, in a state where the IC chip 4 is mounted on the IC mounting substrate 7, the crystal connection terminal 9a (GND) is connected to the IC terminal 50 (GND), and the X1 terminal 9a (X1) is connected to the terminal X1. The X2 terminal 9a (X2) is connected to the X2 terminal. Here, the crystal connection terminal at the lower right in FIG. 3 is a dummy or GND terminal, and is connected to the open or GND terminal, and uses the coreless solder ball 6a to hold the crystal resonator 2 evenly. It may be connected to the crystal unit 2.

  Further, as shown in FIG. 5, the temperature compensation circuit of the temperature compensated crystal oscillator which is an embodiment of the surface mount crystal oscillator of the present invention includes a temperature sensor circuit 20 for generating a temperature compensation voltage, and a temperature sensor circuit 20. A temperature compensation circuit 21 that generates a temperature compensation voltage using an output, a nonvolatile memory 25 for determining a temperature compensation amount, a crystal oscillation circuit 23, and an automatic frequency control input adjustment circuit connected to the crystal oscillation circuit 23 26, a constant voltage circuit 27, and an output buffer circuit 24 for outputting an analog signal output from the crystal oscillation circuit 23.

  More specifically, the temperature sensor circuit 20 generates a voltage whose output changes in a linear function with respect to a temperature change, and the temperature compensation circuit 21 generates a voltage of the crystal resonator 2 from the output voltage of the temperature sensor circuit 20. A voltage is generated to compensate for the frequency temperature change. The nonvolatile memory 25 stores data used for temperature compensation, and the automatic frequency control input adjustment circuit 26 adjusts the voltage gain with respect to the AFC input voltage, and adjusts the frequency variable width by the AFC input voltage. Further, the crystal oscillation circuit 23 constitutes a voltage controlled crystal oscillator by the crystal resonator 2 connected to the outside of the IC chip 4, the built-in amplifier, and the variable capacitance element. Further, the constant voltage circuit 27 generates a voltage used in the IC chip independent of temperature and power supply voltage from the DC power supply voltage, and the output buffer circuit 24 buffers the output of the crystal oscillation circuit and outputs it as an oscillation output. .

  Further, as shown in FIG. 1C, the GND layer 7b is provided inside the IC mounting substrate 7, or the GND layer 7b is provided under the wiring of the IC mounting substrate 7, and the maximum outer dimension of the GND layer 7b is for crystal connection. When the surface mount crystal oscillator of the present invention is mounted on a customer's mounting board by being embedded and formed so as to be larger than the outer frame size of the terminal 9a and the wiring pattern of the IC chip 4, the oscillation frequency of the crystal oscillator is Avoid fluctuations.

  Thus, since the GND layer is formed under the wiring pattern of the IC mounting substrate 7 and the IC mounting electrode, when the surface mounting crystal oscillator of the present invention is mounted on a mounting substrate such as a cellular phone, the crystal connection terminal 9a and the crystal connection terminal 9a, the wiring pattern of the IC chip 4 and the capacitance between the mounting substrate and the oscillation frequency are prevented from changing.

  As described above, in the temperature compensated crystal oscillator which is the first embodiment of the surface mount crystal oscillator according to the present invention, the IC chip mounted on the IC mounting substrate by the coreless solder ball which is less expensive than the cored solder ball. Using the height as a positioning reference, the crystal resonator connection terminal of the IC mounting substrate and the crystal resonator terminal are connected, so that crystal oscillators can be manufactured at the individual or wafer level with high accuracy, low cost, and high productivity. Will be able to.

Example 2
In Example 2, an anisotropic conductive sheet is used as a conductor connecting an IC mounting substrate and a crystal resonator.

  That is, as shown in FIG. 6, the temperature-compensated crystal oscillator according to the second embodiment of the surface mount crystal oscillator of the present invention is mounted on the main surface of the upper surface of the IC mount substrate 7 made of ceramic, crystal plate, or glass plate. Bumps (solder or gold bumps) 5 or an IC chip 4 mounted by flip-chip bonding, and a ceramic or quartz plate 2a, 2b on the main surface of the upper surface of the IC chip 4 and inside thereof A crystal package 2 (referred to as a crystal resonator) formed by bonding and holding the crystal piece 3 to the crystal holding terminal 3b with a conductive adhesive 3a is bonded, and the upper opening of the crystal package 2 is covered with a lid 8 made of Kovar or a crystal plate. It is hermetically sealed by welding or the like.

  Even if an insulating epoxy resin 11 is filled between the lower surface main surface of the IC chip 4 mounted on the upper surface main surface of the IC mounting substrate 7 by IC chip bumps 5 or flip chip bonding and the upper surface main surface. Good.

  Then, the vertical height h of the IC chip 4 bonded to the IC mounting substrate 7 via the IC mounting bumps 5 is used as a positioning reference, and the crystal resonator connection terminal 9a and the crystal resonator 2 of the IC mounting substrate 7 are used. An IC chip 4 and the crystal unit 2 are bonded to each other by connecting an annular (frame type) anisotropic conductive sheet 6b (see FIG. 8) as a conductor to a terminal 9b of the crystal unit provided on the bottom surface of the crystal unit. Fix with agent 4a.

  The anisotropic conductive sheet 6b retains insulation in the surface direction of the sheet, has conductivity in the thickness direction thereof, and is electrically sandwiched in the thickness direction and pressed to electrically connect the crystal resonator connection terminal 9a and the crystal. The terminal 9b of the vibrator is connected.

  However, since the anisotropic conductive sheet 6b is deformed in the thickness direction by pressing, the vertical height h of the IC chip 4 is used as a reference position for positioning as in the first embodiment.

  Here, as the anisotropic conductive sheet 6a, for example, a nickel particle having a thickness of 30 μm and a particle diameter of 2 μm as a conductive particle (adhesive strength) or a carbon-based conductive fiber is used. An anisotropic conductive sheet (no adhesive force) oriented with a high density in the thickness direction of the insulating silicone having a sheet thickness of, for example, 200 μm and a conductive fiber diameter of 30 μm (for example, Shin-Etsu Polymer) Company / MAF type) is used. The anisotropic conductive sheet 6b may be individually affixed to the upper surface of the IC mounting substrate 7 of the individual crystal oscillator, or it may be a waste when manufacturing the crystal oscillator at the wafer level. In order to save, a tape-like anisotropic conductive sheet may be affixed to the wafer and then divided into individual pieces.

  Further, the main surface of the lower surface (back surface) of the IC mounting substrate 7 is shown in FIG. 7, and as described in detail in the first embodiment, the surface mounting crystal oscillator of the present invention is mounted on a customer mounting substrate (not shown). Is provided with an oscillator mounting terminal (external terminal) 30.

  Further, as shown in FIG. 9 and described in detail in Example 1, the top surface of the IC mounting substrate 7 is connected to the crystal unit 2 by using the anisotropic conductive sheet 6b. A connection terminal 9a is provided. When the anisotropic conductive sheet 6a having adhesive force is used, the solder bumps 28 for connection are formed in advance on the crystal connection terminals 9a or the crystal resonator terminals 9b in order to narrow the gap.

  Also in the temperature compensated crystal resonator of the second embodiment, a temperature compensation circuit as shown in FIG. 5 and described in detail in the first embodiment is provided.

  Further, similarly to the first embodiment, a GND layer may be embedded in the IC mounting substrate 7.

Example 3
Example 3 is an example of a temperature-compensated crystal oscillator in which the crystal resonator connecting substrate 29 and the crystal resonator 2 are connected by a commercially available anisotropic conductive sheet as a conductor with or without adhesive force. About.

  In the crystal oscillator using the anisotropic conductive sheet 6c having adhesive force according to the third embodiment, as shown in FIG. 10, the crystal connection terminal 9a of the crystal resonator connection substrate 29 made of a ceramic, a crystal plate or a glass plate is used. The connecting solder bumps 28 are formed. An IC mounting bump (solder or gold) 5 is placed on the main surface of the upper surface of the IC chip 4 and is made of a ceramic, a quartz plate or a glass plate, and is made of quartz packages 2a and 2b each having a quartz piece 3 placed therein. The bottom surface of the crystal unit 2 is connected via the electrode pad 5a. Next, after placing the crystal resonator connecting terminal 9b and the annular (frame-type) anisotropic conductive sheet 6c (see FIG. 12), the crystal resonator connecting terminal 9a is placed facing each other, and is connected by pressurizing and heating. . At this time, the IC chip 4 may be fixed with an adhesive 4a for reinforcement.

  Further, as shown in FIG. 11, an oscillator mounting terminal (external terminal) 30 for mounting the surface mounting crystal oscillator of the present invention on a customer mounting board is provided on the lower surface (back surface) of the crystal resonator connection substrate 29. Is provided. When the surface mount crystal oscillator of the present invention is mounted on a mounting substrate such as a mobile phone by connecting the IC chip 4 to the crystal resonator 2, the crystal resonator connection terminal 10, the IC terminal 50 (X1), the IC terminal Since the capacitance between the mounting substrates does not change to 50 (X2), a change in the oscillation frequency is avoided.

  Further, similarly to the first embodiment, a GND layer may be embedded in the crystal resonator connection substrate 29.

  Further, FIG. 13A is a plan view of the crystal resonator 2 viewed from the IC terminal 50 side. Here, a crystal resonator connection terminal 10 connected to the crystal piece 3 by a via hole is provided, and the characteristics of the crystal resonator 2 can be measured.

  At both ends of the ceramic plate 2 b, crystal connection terminals 9 b for connecting to the crystal resonator connection substrate 29 are provided, and are connected to both ends of the IC terminal 50.

  Further, the IC terminal 50 (X1) and the IC terminal 50 (X2) at the center of the ceramic plate 2b are connected to the crystal resonator connection terminal 10 (X1) and the crystal resonator connection terminal 10 (X2), respectively.

  Here, FIG. 13B is a plan view after the IC chip 4 is mounted on the IC terminal 50.

Example 4
In the anisotropic conductive sheet with adhesive force of Example 3, the anisotropic conductive sheet 6c is pressurized, and the conductive particles in the binder are brought into contact with each other to make the connecting solder bumps 28 and the crystal connection terminals 9b conductive. At that time, the crystal unit 2 and the crystal unit connection substrate 29 can be bonded by heating the binder.

  On the other hand, in the crystal oscillator using the anisotropic conductive sheet having no adhesive force of Example 4, the anisotropic conductive sheet is added without forming the connecting solder bumps 28 as shown in FIG. By pressing, it can be conducted with the crystal connection terminal 9b. At that time, in order to maintain positioning and mechanical strength, the adhesive 4a is applied between the IC chip 4 and the crystal resonator connecting substrate 29 and heated to fix both.

  Here, as the above-described adhesive 4a, an insulating epoxy adhesive that adheres by applying temperature is suitable. Further, as shown in FIG. 15, an oscillator mounting terminal (external terminal) 30 is provided on the lower surface (bottom surface) of the crystal resonator connection substrate 29.

  When the surface mount crystal oscillator of the present invention is mounted on a mounting substrate such as a mobile phone by connecting the IC chip 4 to the crystal resonator 2, the crystal resonator connection terminal 10, the IC terminal 50 (X1), the IC Since the capacitance between the terminal 50 (X2) and the mounting board does not change, a change in the oscillation frequency is avoided.

  Further, similarly to the first embodiment, a GND layer may be embedded in the crystal resonator connection substrate 29.

Other Embodiments In the first and second embodiments, the IC chip 4 is connected to the IC mounting substrate. However, as in the third and fourth embodiments, a configuration in which the IC chip 4 is connected to the crystal resonator side may be used. In the third and fourth embodiments, the IC chip 4 is connected to the crystal resonator side. However, as in the first and second embodiments, the IC chip 4 may be connected to the IC mounting substrate.

1 Temperature compensated crystal oscillator (surface mount crystal oscillator)
2 Crystal package (quartz crystal)
2a, 2b, 2c Ceramic plate 3 Crystal piece 3a Conductive adhesive 4 IC chip 5 IC mounting bump 6 Conductor 6a Coreless solder ball 6b, 6c Anisotropic conductive sheet 7 IC mounting substrate (crystal resonator connection substrate)
7b GND layer 8 Lid 9a, 9b Crystal connection terminal 10 Crystal resonator connection terminal 11 Protective adhesive 12a, 12b Recess 13 Metal ring 14 Anisotropic conductive resin 15 Joint terminal 20 Temperature sensor circuit 21 Temperature compensation circuit 23 Crystal oscillation circuit 24 Output buffer circuit 25 Non-volatile memory 26 Automatic frequency control input adjustment circuit (AFC)
27 Constant voltage circuit 28 Solder bump 29 for connection 29 Crystal oscillator connection substrate 30 Oscillator mounting terminal 50 IC terminal

Claims (17)

  In a surface-mount crystal resonator formed by laminating and bonding an IC mounting substrate or a crystal connection substrate to which an IC chip is bonded, and a crystal resonator including a hermetically sealed crystal piece and a crystal package, the IC A crystal oscillator for surface mounting, wherein a crystal resonator connection terminal of the mounting substrate or the crystal connection substrate and a terminal of the crystal resonator are connected by a conductor.   The surface-mount crystal oscillator according to claim 1, wherein the conductor is made of a coreless solder ball.   3. The surface mount crystal oscillator according to claim 2, wherein a diameter of the coreless solder ball is 50 μm to 300 μm.   The surface-mount crystal oscillator according to claim 1, wherein the conductor is made of an anisotropic conductive sheet.   The surface-mount crystal oscillator according to claim 4, wherein the anisotropic conductive sheet is formed in an annular shape in a plan view.   The surface-mount crystal oscillator according to claim 4, wherein the anisotropic conductive sheet is formed in a tape shape in a plan view.   The surface-mount crystal oscillator according to claim 4, wherein the anisotropic conductive sheet has adhesiveness.   The surface-mount crystal oscillator according to claim 4, wherein the anisotropic conductive sheet does not have adhesiveness.   2. The surface mount crystal oscillator according to claim 1, wherein the IC chip is bonded to the IC mounting substrate or the crystal connection substrate by a gold bump.   2. The surface mount crystal oscillator according to claim 1, wherein the IC chip is bonded to the IC mounting substrate or the crystal connection substrate by solder bumps.   2. The surface mount crystal oscillator according to claim 1, wherein a joint portion between the IC chip and the IC mounting substrate or the crystal connection substrate is protected with an insulating epoxy adhesive.   2. The surface mount crystal oscillator according to claim 1, wherein an insulating epoxy adhesive is filled between the IC mounting substrate or the crystal connection substrate and the IC chip.   2. The surface mount crystal oscillator according to claim 1, wherein a GND layer is embedded in the IC mounting substrate.   2. The surface-mount crystal oscillator according to claim 1, wherein a GND layer is embedded in the IC mounting substrate so as to correspond to a portion under the wiring formed on the IC mounting substrate.   A GND layer is embedded in the IC mounting substrate so that the maximum external dimension of the GND layer is larger than the outer dimensions of the crystal connection terminals and the wiring patterns of the crystal connection terminals and the IC chip. The surface-mount crystal oscillator according to claim 1, wherein the surface mount crystal oscillator is formed.   16. The surface mount crystal oscillator according to claim 1, wherein the surface mount crystal oscillator is a temperature compensated crystal oscillator.   A temperature sensor circuit for generating a temperature compensation voltage; a temperature compensation circuit for generating a temperature compensation voltage using an output of the temperature sensor circuit; a nonvolatile memory for determining a temperature compensation amount; 17. The temperature compensated crystal oscillator according to claim 16, wherein an oscillation circuit and a buffer circuit for outputting an analog signal output from the crystal oscillation circuit are stored.

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