JP2006217665A - Temperature compensated crystal oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small temperature compensated crystal oscillator in which all components can be mounted in one cavity of a container. <P>SOLUTION: In the temperature compensated crystal oscillator, a cavity portion is arranged in the major surface of a container body, terminal electrodes are arranged at four corners on the major surface, a part of an IC chip being contained in the cavity portion and connected electrically with a quartz resonator is arranged between adjacent terminal electrodes, and an electrode for controlling operation of the IC chip is led out from the interior of the cavity portion through a region between adjacent terminal electrodes. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention belongs to a temperature compensated crystal oscillator.

Conventionally, as an electronic component in which an IC chip and a chip-shaped electronic component element are mounted in the same cavity, a temperature compensated crystal oscillator or the like can be exemplified.

 For example, a temperature-compensated crystal oscillator has conventionally been provided with predetermined electronic component elements, such as a crystal resonator, a transistor, a temperature-sensitive element, a capacitor element, and a resistor element, that constitute the temperature-compensated crystal oscillator on a glass epoxy resin substrate. It was mounted on the circuit. In addition, these crystal resonators, transistors, temperature sensitive elements, capacitor elements, resistance elements, and the like are accommodated in a box-shaped container having an opening on the surface to form one temperature compensated crystal oscillator.

In such a structure, there is a limit to downsizing in order to mount all the components in one cavity of the container body.
Japanese Patent Application Laid-Open No. 7-106881

The temperature-compensated crystal oscillator according to the present invention includes a cavity portion disposed on the main surface of the container body, terminal electrodes disposed on the four corners of the main surface, and electrically connected to the crystal resonator. A part of the IC chip housed in the part is disposed between the adjacent terminal electrodes, and an operation control electrode for controlling the operation of the IC chip is provided in the cavity part through the region between the adjacent terminal electrodes. It is derived from the inside to the outside.

  The temperature compensated crystal oscillator according to the present invention is the above temperature compensated crystal oscillator, wherein the IC chip is connected to an IC connection electrode pad disposed on a bottom surface of the cavity portion via a bump member. It is characterized by.

  Furthermore, the temperature compensated crystal oscillator of the present invention is characterized in that, in the temperature compensated crystal oscillator, an IC chip sealing resin is filled in the cavity portion.

  In the present invention, with the above configuration, all components can be mounted in one cavity of the container body, and downsizing can be realized.

The temperature compensated crystal oscillator of the present invention will be described in detail below with reference to the drawings.

 FIG. 1 is an external perspective view of a temperature-compensated crystal oscillator according to the present invention, and FIG. 2 is a sectional view thereof. FIG. 3 is a bottom view of the container body, and FIG. 4 is a diagram showing a pattern of the bottom surface of the cavity portion of the container body.

 In the figure, the temperature-compensated crystal oscillator includes a substantially rectangular parallelepiped container body 1 having a flat upper surface (hereinafter referred to as a surface) and a concave cavity portion 10 formed on the lower surface (hereinafter referred to as a bottom surface), a rectangular shape. The crystal resonator 2, the IC chip 3 constituting the control circuit, the two chip-like electronic component elements 4 and 5, the metal lid 6 and the filling resin 7 are mainly constituted.

 The container body 1 is configured by integrally laminating a plurality of substantially rectangular ceramic insulating layers 1a and 1b and substantially frame-shaped ceramic insulating layers 1c and 1d having irregularly shaped openings.

The ceramic insulating layers 1a and 1b serve as a partition portion that partitions the region in which the crystal resonator 2 is accommodated from the region in which the IC chip 3 and the chip-shaped electronic component elements 4 and 5 are accommodated, and the ceramic insulating layer 1c, 1d is a leg portion having a frame shape, and thereby, a bottom surface of the partition portion and a concave cavity portion 10 surrounded by the bottom surface and the frame-shaped leg portion are configured.

 External terminal electrodes 11 to 14 are formed at four corners of the bottom surface of the container body 1, respectively.

Further, terminal electrodes 15 to 18 for controlling the operation of the IC chip 3 are formed on the side surface of the container body 1 as necessary.

 In addition, crystal resonator electrode pads 20 and 21 (21 does not appear in the drawing) are formed in the crystal resonator accommodating region on the surface of the container body 1, and the cavity portion 10 of the container body 1 is formed. Inside, there are an IC connection electrode pad 30, an element electrode pad 40 comprising a pair of electrode portions 40a, 40b, an element electrode pad 50 comprising a pair of electrode portions 50a, 50b, and further, these electrode pads 30, 40, A wiring pattern connected to 50 is formed.

 Further, in the thickness direction of the ceramic layers 1a to 1d constituting the container body 1 or the ceramic layers 1a to 1d, the electrode pads 30, 40, 50, the external terminal electrodes 11 to 14, the terminal electrodes 15 to 18, and A wiring pattern for connecting is formed.

 The container body 1 described above is formed using ceramic green to be the ceramic insulating layers 1a to 1d. Specifically, the ceramic green to be the insulating layers 1a to 1d is molded into a predetermined shape, and through holes are formed according to the wiring pattern, and at the same time the through holes are filled with a refractory metal paste such as molybdenum or tungsten. Then, various electrode pads, terminal electrodes, and a conductor film to be a wiring pattern are formed on the surface by printing a refractory metal paste.

 Next, after such a green sheet is laminated and pressure-bonded, a baking treatment is performed.

 Next, the container body 1 is completed by applying Ni plating, flash gold plating, or the like to each external terminal electrode, each electrode pad, and various wiring patterns exposed on the surface of the container body 1.

 That is, various electrode pads, wiring patterns, and terminal electrodes exposed on the surface of the container body 1 are coated with Au.

 On the surface of the container body 1 as described above, a crystal resonator 2 is disposed via conductive adhesives 2a and 2b (not shown in the figure). The quartz resonator 2 includes a vibrating electrode formed on both main surfaces of a rectangular quartz plate that has been cut in a predetermined manner, for example, an AT cut, and an island-shaped extraction electrode portion that extends from the vibrating electrode to one other end. It is composed of The crystal resonator 2 is connected to the crystal resonator electrode pads 20 and 21 via the bump members 22 and 23 via the conductive adhesives 2a and 2b.

 The crystal resonator 2 mounted on the surface side of the container body 1 is hermetically sealed by a metal lid 6. The metal lid 6 is made of a metal material such as Kovar or 42 alloy, has a thickness of, for example, 0.1 mm, and is attached to a frame-like seam ring 61 brazed to the sealing conductor pattern on the surface of the container body 1. Welded and joined.

 Examples of the electronic component elements 4 and 5 include capacitors.

As shown in FIG. 3, the electronic component element 4 is an element electrode pad 40 including a pair of electrode portions 40a and 40b, and the electronic component element 5 is an element electrode including a pair of electrode portions 50a and 50b. Bonded to the pad 50 through conductive resin adhesives 41 and 51 containing Ag powder.

The conductive resin adhesives 41 and 51 are applied by applying and applying a conductive resin paste made of Ag powder, epoxy resin, phenol resin or the like using a dispenser, for example. Join.

 The IC chip 3 controls an oscillator, for example, and includes, for example, an amplifying unit, a temperature compensating unit, and a sensitive unit.

Examples of the amplifying means include an amplifying inverter, and the temperature compensating means includes a computing means, a temperature compensation data storage means, a varicap diode, a load capacitor, a resistance means, and the like.

 In such an IC chip 3, for example, a bump member is formed on the electrode on the surface or bottom surface of the IC chip 3, and ultrasonic bonding or conductive adhesive is interposed between the bump member and the IC connection electrode pad 30. Bonded by face bonding.

Further, the IC chip 3 may be die-connected and bonded with a wire.

 The capacitor which is the electronic component element 4 is connected, for example, between the IC chip 3 and the OUT external terminal electrode 12 so that one becomes a ground potential.

This removes a DC component that becomes noise in the output signal.

 The capacitor, which is the electronic component element 5, is connected between the IC chip 3 and the VCC external terminal electrode 11, and removes high-frequency noise superimposed on the power supply voltage supplied to the VCC external terminal electrode 11.

 The electronic component elements 4 and 5 and the IC chip 3 are accommodated in a substantially cross-shaped cavity portion 10 provided on the rectangular bottom surface of the container body 1. The external terminal electrodes 11 to 14 are arranged in the four generated regions, that is, the four corners on the lower surface of the container body defined by the cross-shaped cavity portion 10.

 Here, the pair of terminal electrodes provided at both ends of the chip-shaped electronic component elements 4 and 5 are opposed along the side surface of the IC chip 3 adjacent to the chip-shaped electronic component elements 4 and 5 as shown in FIG. The chip-shaped electronic component element 4 is disposed by connecting the pair of electrode portions 40a, 40b, 50a, and 50b provided on the bottom surface of the cavity portion 10 via the conductive adhesives 41 and 51. 5 is mounted on the bottom of the cavity of the container body 1.

 Further, as shown in FIG. 3, the IC chip 3 straddles a pair of overhanging portions facing each other across the center portion among the four overhanging portions extending in four directions from the center portion of the cross-shaped cavity portion 10. The chip-like electronic component elements 4 and 5 are arranged on the remaining overhanging portion so as to straddle the pair of electrode portions 40a, 40b, 50a and 50b.

 Here, the pair of electrode portions 40a, 40b, 50a, 50b are opposed to each other with a predetermined interval in the short direction of the lower surface of the container body, and the longitudinal direction of the chip-like electronic component elements 4, 5 is the lower surface of the container body. The shape is arranged parallel to the short direction.

 Thereby, the container body 1 is made very compact by the arrangement of the electronic component element 4, the IC chip 3, and the electronic component element 5 and the arrangement relationship with the external terminal electrodes 11-14.

 The cavity portion 10 is filled with a filling resin 7 in order to firmly bond the above-described IC chip 3 and electronic component elements 4 and 5 and to improve moisture resistance reliability. The filling resin 7 is made of, for example, at least two kinds of filling resins. For example, the filling resin 7 is a resin layer that is mainly filled and cured on the bottom surface side of the cavity portion 10 and a resin layer that is filled and cured on the resin layer. Specifically, the cavity portion 10 is made of a resin material having a relatively large shrinkage rate that is filled and cured on the bottom surface side. It is a material with many resin components, such as an epoxy resin generally called underfill resin. This resin layer is filled and cured to such an extent that at least the upper surface of the IC chip 3 is completely covered.

 That is, due to the stress generated by the shrinkage of the resin layer filled between the IC chip 3, the electronic component elements 4, 5 and the bottom surface of the cavity portion 4, the bonding strength between them is improved.

In addition, stress generated by contraction of the resin layer formed so as to completely cover the IC chip 3 is generated toward the IC chip 3. Thereby, the stress works so as to press against the bottom surface side of the cavity portion 10 from the upper surface side of the IC chip 3, and the bonding strength of the IC chip 3 bonded to the bottom surface of the cavity portion 10 is improved.

 Further, the resin layer filled on the surface is filled and cured with concern that sufficient moisture resistance cannot be obtained only by the resin layer covering the IC chip 3 and the electronic component elements 4 and 5. Thereby, the joining strength and moisture resistance reliability of the IC chip 3 and the electronic component elements 4 and 5 mounted in the cavity portion 10 are improved. It is important that the filled resin is not protruded from the opening surface of the cavity portion 10. This is because the surface-mounted crystal oscillator is stably placed on the printed wiring board.

 Further, as shown in FIGS. 3 and 4, a pair of electrode portions 40 a and 40 b constituting the component mounting electrode pad 40 on which the electronic component element 4 is arranged and a component mounting electrode pad 50 on which the electronic component element 5 is arranged are provided. Cutout portions 42 (42a, 42b) and 52 (52a, 52b) are formed on the outer sides of the pair of electrode portions 50a, 50b constituting the electrode portions 40a, 40b and 50a, 50b. Yes.

 Specifically, for example, the pair of electrode portions 40a and 40b on which the electronic component element 4 is placed have a predetermined distance x in accordance with the distance between the pair of external electrodes of the electronic component element 4. Are arranged so as to face each other. One side facing each other is called an inner side side, and one electrode part, for example, a side facing the inner side side at 40a is called an outer side side in FIG.

 For example, although the electrode part 40a is not a perfect rectangular shape from the connection with a wiring pattern, it is a substantially rectangular shape as a whole. A substantially rectangular cutout portion 42a is formed on the outer side of the electrode portion 40a. For example, the size in the width direction of the shape of the rectangular cutout portion 42a is shorter than the length of the outer side of the electrode portion 40a, and the shape of the cutout portion 42a in the rectangular shape is cut. The dimension is shorter than the dimension in the opposing direction of the electrode part 40a, and the center line on the outer side of the electrode part 40a and the center line in the width direction of the shape of the cutout part 42a are substantially the same. Yes.

 The electronic component elements 4 and 5 are mounted on such electrode portions 40a and 40b and 50a and 50b by supplying and curing a conductive resin paste to be the conductive resin adhesives 41 and 51, and mounting.

 Thereby, for example, it can be regulated that the conductive resin paste supplied to the electrode portions 40a and 40b is drawn toward the notches 42a and 42b, and the conductive resin paste spreads toward the interval x.

 Therefore, when the conductive resin paste is supplied onto the electrode portions 40a and 40b and the electronic component element 4 is further placed thereon, even if the conductive resin paste spreads, the gap between the external terminal electrodes of the electronic component element 4 is increased. There is no such thing as a short circuit.

 The conductive resin paste described above is drawn toward the notches 42a and 42b because the surfaces of the electrode portions 40a and 40b are Au-plated and exposed from the notches 42a and 42b. This is because the ceramic material is exposed on the bottom surface, and in this case, since the surface state of the bottom surface of the cavity portion 10 is rougher than the surface of the electrode portions 40a and 40b, the conductive resin paste easily flows.

 As for the structure in which the electronic component element 4 is mounted on the electrode portions 40a and 40b using the conductive adhesive 41, as in the case of the bottom surface of the cavity portion 10, it is difficult to efficiently apply solder, that is, When solder cannot be supplied by a printing method, or when the structure is difficult to clean, such as the cavity portion 10, the cavity portion 10 is juxtaposed with an element that dislikes application of heat at around 200 ° C., for example, the IC chip 3. In particular, the flow direction of the conductive adhesive 41 can be regulated. Therefore, depending on the layout design of the IC chip 3 and the electronic component element 4 in the cavity 10, the conductive adhesive 41 depends on the layout design. Efficient layout design without short circuit is possible.

 Further, the notches 42a and 42b formed on the outer sides of the electrode portions 40a and 40b are formed with dents corresponding to the thickness of the electrode portions.

 Accordingly, when the conductive resin paste is applied and the electronic component element 4 is mounted, a fillet is formed on the bottom surface or the side surface of the terminal electrode portion of the electronic component element 4, and the bonding strength can be improved. At the same time, reliability such as shock resistance and vibration resistance can be improved.

 In the above-described embodiment, for example, the notches 42a and 42b are formed on the outer side that is paired with the inner side where the electrode portions 40a and 40b face each other. In consideration of the arrangement direction of the electronic component element, for example, the IC chip 3, it may be formed on the other side except the inner side sides of the electrode portions 40a and 40b.

 The outer side may be any of the three sides other than the inner sides of the pair of electrode portions 40a and 40b facing each other. Further, the shape of the electrode portions 40a and 40b is not limited to a rectangular shape.

1 is an external perspective view of a temperature compensated crystal oscillator of the present invention. It is sectional drawing of the temperature compensation type | mold crystal oscillator of this invention. It is a bottom view of the state which omitted the resin of the temperature compensation type crystal oscillator of the present invention. It is a schematic plan view explaining the wiring pattern in the plane used as the cavity part bottom face of the temperature compensation type | mold crystal oscillator of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Container body 2 ... Crystal oscillator 3 ... IC chip 4, 5 ... Electronic component element 6 ... Metal lid body 40, 50 ... Component mounting electrode pads 40a, 40b, 50a, 50b .... Electrode part
41a, 41b, 44a, 44b, 45a, 45b, 46a, 46b ・ ・ Notch

Claims (3)

While arranging the cavity part on the main surface of the container body, arranging the terminal electrodes at the four corners of the main surface,
A part of the IC chip that is electrically connected to the crystal unit and accommodated in the cavity is disposed between adjacent terminal electrodes,
A temperature-compensated crystal oscillator, wherein operation control electrodes for controlling the operation of the IC chip are led out from the inside of the cavity portion to the outside through a region between the adjacent terminal electrodes. 2. The temperature compensated crystal oscillator according to claim 1, wherein the IC chip is connected to an IC connection electrode pad disposed on a bottom surface of the cavity portion via a bump member. 3. The temperature compensated crystal oscillator according to claim 1, wherein the cavity portion is filled with a resin for sealing an IC chip.

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