JP2005318524A - Piezoelectric oscillator and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a miniaturized piezoelectric oscillator in which a frequency can be finely adjusted even after resin molding, and a method of manufacturing the same. <P>SOLUTION: There are provided a vibrator package 30 which houses a piezoelectric vibrating piece 32 therein, and a semiconductor device 80 which incorporates an oscillation circuit electrically connected with this vibrator package 30. The vibrator package 30 and the semiconductor device 80 are fixed on mutually difference surfaces of a lead frame 10, respectively, and molded with a resin 21 so as to externally expose a transparent lid body 39 of the vibrator package 30, and a lead terminal 11 of the lead frame 10 is connected with the semiconductor device 80 by a vamp 15. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a piezoelectric oscillator including a piezoelectric vibrator package containing a piezoelectric vibrating piece, and a semiconductor element including an oscillation circuit that oscillates the piezoelectric vibrating piece, and a method of manufacturing the same.

Piezoelectric oscillators are widely used in packages in small information devices such as HDDs (hard disk drives), mobile computers, and IC cards, and mobile communication devices such as mobile phones, car phones, and paging systems. Yes.
21 shows a configuration example of a conventional piezoelectric oscillator (see Patent Document 1). In the figure, the piezoelectric oscillator fixes the semiconductor element 1 to one surface of the lead frame 5 by bonding or the like, and this lead frame. The piezoelectric vibrator 4 housed in a cylindrical package is fixed to the other surface of the semiconductor 5, the lead terminals of the semiconductor element 1 and the lead frame 5 are connected by the bonding wire 3, and the whole is molded with the resin 6. It is configured.

Such a structure can avoid various inconveniences when the piezoelectric vibrating piece and the oscillation circuit are accommodated in the same package.
That is, if the piezoelectric vibrating piece and the oscillation circuit are simultaneously accommodated in the resin package, gas generated at the time of curing may adhere to the piezoelectric vibrating piece, leading to performance degradation.
Therefore, as described above, the piezoelectric vibrating piece and the oscillation circuit are accommodated in separate packages and fixed to different surfaces on the lead frame, so that these disadvantages can be avoided and the configuration can be reduced. is there.
Such a configuration is also described in other patent documents (see Patent Document 2).

Japanese Utility Model 1-82507 microfilm JP 7-162236 A

However, in the conventional piezoelectric oscillator, no countermeasure is taken when the frequency deviation of the piezoelectric vibrator becomes a problem after resin molding.
That is, in recent years, extremely high accuracy is required for the frequency performance of the piezoelectric oscillator, and after sealing the package of the piezoelectric vibrator, the frequency of the piezoelectric vibrator becomes a problem due to the influence of the subsequent manufacturing process and the like. When it changes to the extent, it becomes impossible to ship as a product, each part is wasted, and the manufacturing yield is lowered, resulting in an increase in manufacturing cost.

  An object of the present invention is to provide a small piezoelectric oscillator capable of finely adjusting the frequency even after resin molding and a method for manufacturing the same.

  According to the first aspect of the present invention, the above object includes a vibrator package that contains a piezoelectric vibrating piece therein, and a semiconductor element that includes an oscillation circuit that is electrically connected to the vibrator package. The vibrator package and the semiconductor element are fixed to different surfaces of the lead frame, respectively, and resin-molded so that the transparent lid of the vibrator package is exposed to the outside, and the lead frame lead The terminal is achieved by a piezoelectric oscillator joined to the semiconductor element by a bump.

According to the configuration of the first aspect of the invention, since the transparent lid of the vibrator package is resin-molded so as to be exposed to the outside, the transparent lid is allowed to pass through from the outside even after assembly. The frequency adjustment of the piezoelectric vibrating piece in the vibrator package can be performed by irradiating the laser beam for frequency adjustment to the laser beam. In other words, after sealing the piezoelectric vibrator package, if the frequency of the piezoelectric vibrator changes to a problem level due to the influence of the subsequent manufacturing process, etc. The frequency can be adjusted by evaporating with the laser beam and using a mass reduction method.
In addition, since the lead terminal of the lead frame is bonded to the semiconductor element by a bump, the size of the piezoelectric oscillator is not required because it is not necessary to draw a bonding wire as compared with the case where the semiconductor element and the lead terminal are connected by wire bonding. Can be reduced.
Thus, according to the present invention, it is possible to provide a small piezoelectric oscillator capable of finely adjusting the frequency even after resin molding.
In addition to the frequency adjustment, it is also possible to cut the wiring in the package that has become unnecessary after manufacturing the product.

A second invention is characterized in that, in the configuration of the first invention, the vibrator package and the semiconductor element are joined by bumps.
According to the configuration of the second invention, since the vibrator package and the semiconductor element are bonded by the bump, the lead wire and the semiconductor element are bonded by the bump in the first invention. Is eliminated, and the generation of parasitic capacitance can be effectively prevented.

According to a third invention, in the configuration of the second invention, the bump for joining the vibrator package and the semiconductor element is formed by overlapping a plurality of bumps.
According to the configuration of the third invention, since the bump for joining the vibrator package and the semiconductor element is formed by overlapping a plurality of bumps, the distance between the vibrator package and the semiconductor element is one bump. Even if they are so far apart that they cannot be joined, the vibrator package and the semiconductor element can be reliably bump-joined. That is, according to the configuration of the first invention, the vibrator package and the semiconductor element are respectively fixed to different surfaces of the lead frame, and the lead frame and the semiconductor element are bump-bonded. Then, the vibrator package and the semiconductor element are separated from each other by at least the height of the bump that joins the semiconductor element and the lead terminal to the thickness of the lead frame. However, according to the configuration of the third aspect of the invention, the vibrator package and the semiconductor element can be reliably bump-bonded by overlapping a plurality of bumps.

According to a fourth aspect of the present invention, in any one of the first to third aspects, at least a bonding region of the lead frame fixed to the vibrator package and the semiconductor element is other than the bonding region of the lead frame. In comparison, at least a part of the lead frame is deformed so as to be positioned in a direction away from the transparent lid.
According to the configuration of the fourth aspect of the invention, at least a part of the lead frame is deformed so that at least a bonding region of the lead frame fixed to the vibrator package and the semiconductor element is located in a direction away from the transparent lid. Therefore, the transparent lid of the vibrator package is pressed in the mold in the direction in which a part of the lead foam is deformed during molding. For this reason, the lid is pressed by the inner surface of the molding die at the time of molding so that the resin does not enter the surface of the lid, and there is no burr between the inner surface of the mold and the lid. It does not occur. Thus, it is not necessary to deburr the lid surface after manufacturing, and it is formed so as to be appropriately exposed on the entire surface of the transparent lid.

  According to the fifth aspect of the present invention, there is provided a lead frame including a support frame that integrally supports the outer ends of the plurality of lead terminals and the outer ends of the holding lead portions extending from the island portions serving as die pads. A step of bonding and fixing a semiconductor element containing an oscillation circuit to the lead terminal on one side of the lead frame by a bump, a step of fixing a vibrator package to the island part on the other side of the lead frame, This is achieved by a method of manufacturing a piezoelectric oscillator including a step of resin-molding a semiconductor element and the vibrator package such that a transparent lid of the vibrator package is exposed.

According to the configuration of the fifth invention, the transparent lid of the vibrator package is exposed when the lead frame is molded by the resin mold in a state where the semiconductor element and the vibrator package are fixed. Then, even after molding, the frequency of the piezoelectric vibrating piece in the vibrator package can be adjusted by transmitting the transparent lid from the outside and irradiating the inside with laser light for frequency adjustment. . That is, after sealing the piezoelectric vibrator package, if the frequency of the piezoelectric vibrator changes to a problem level due to the influence of the subsequent manufacturing process, etc. The frequency can be adjusted by evaporating with the laser beam and using a mass reduction method.
In addition, since the lead terminal and the semiconductor element are joined by bumps, the size of the piezoelectric oscillator can be reduced because it is not necessary to draw a bonding wire for electrically connecting the lead terminal and the semiconductor element.

A sixth invention is characterized in that, in the configuration of the fifth invention, the vibrator package and the semiconductor element are joined by bumps in the step of fixing the vibrator package.
According to the configuration of the sixth aspect of the invention, since the vibrator package and the semiconductor element are bonded by the bump in the step of fixing the vibrator package, the vibrator package and the semiconductor element are bonded by wire bonding, etc. A process is not required and the manufacture of the piezoelectric oscillator is facilitated.

According to a seventh aspect of the present invention, in the configuration of any one of the fifth and sixth aspects, in the resin molding step, the transparent lid is one mold for molding, and the depth thereof is the vibrator package. The transparent lid body is displaced inward within the mold by contacting the inner surface of the mold smaller than the thickness of the mold and aligning the one mold with the other mold with reference to the position of the support frame. As described above, at least a part of the lead frame is deformed.
According to the configuration of the seventh invention, since the depth of one of the molds is made smaller than the thickness of the vibrator package, the transparent lid of the vibrator package is brought into contact with the inner surface of this one mold. The vibrator package side is displaced inward, that is, the semiconductor element side by aligning one mold and the other mold with the position of the support frame and performing resin molding. At least a part of is deformed. In this process, the transparent lid of the vibrator package is pushed in the mold in the direction in which a part of the lead foam is deformed. For this reason, the lid is pressed by the inner surface of one mold and is in close contact, so that the resin does not enter the surface side of the lid and a burr is generated between the inner surface of the mold and the lid. Absent. Thus, it is not necessary to deburr the lid surface after manufacturing, and the entire surface of the transparent lid can be appropriately exposed.

According to an eighth aspect of the invention, in the configuration of the seventh aspect, in the resin molding step, a convex portion is provided on the inner surface of the other mold, and the lead terminal is pressed against the vibrator package by the convex portion. One type is combined with the other type.
According to the configuration of the eighth invention, in the resin molding step, the convex portion is provided on the inner surface of the other mold, and the lead terminal is pressed against the vibrator package by this convex portion. Therefore, even if the stress generated when one mold is matched with the other mold is applied to the lead terminal, the lead terminal portion pressed against the vibrator package by the convex portion is prevented from being deformed, and the lead The bonding state by the bump of the terminal and the semiconductor element can be kept good.

According to a ninth invention, in the configuration of the eighth invention, the convex portion is formed so as to be interrupted on an inner surface of the other mold.
By the way, for example, when the convex part is formed so as to surround the semiconductor element, the resin attached to the region surrounded by the convex part is separated from the resin attached to the other region, It becomes easy to peel from the semiconductor element. However, according to the ninth aspect of the invention, since the convex portion is formed so as to be interrupted on the inner surface of the other mold, the convex portion is surrounded by the resin attached to the portion where the convex portion is interrupted. The resin adhering to the other region and the resin adhering to the other region are integrally connected. Therefore, it can suppress that resin peels from a semiconductor element.

1 to 5 show an embodiment of a piezoelectric oscillator according to the present invention. FIG. 1 is a schematic plan view thereof, FIG. 2 is a schematic sectional view taken along line AA of FIG. 1, and FIG. FIG. 4 is a schematic cross-sectional view taken along line B-B, FIG. 4 is a schematic cross-sectional view taken along line CC in FIG. 1, and FIG.
In these drawings, a piezoelectric oscillator 70 is an IC chip that is a semiconductor element including a lead frame 10, a vibrator package 30 containing a piezoelectric vibrating piece, and an oscillation circuit electrically connected to the vibrator package 30. 80.
That is, the piezoelectric oscillator 70 fixes the IC chip 80 on one surface (upper surface in FIG. 2) of the lead frame 10, and fixes the vibrator package 30 on the other surface (lower surface in FIG. 2). Only 30 lids 39 are exposed and molded with resin 21.

Here, the structure of the lead frame 10 will be described first.
As the lead frame 10, those commonly used in manufacturing a package element can be used. For example, an Fe alloy such as 42 alloy, or a Cu alloy such as Cu—Sn, Cu—Fe, Cu—Zn, or Cu—Ni. An alloy or a ternary alloy obtained by adding a third element to these is used, and has an island portion 12 and a plurality of lead terminals 11 as shown in FIG.
The island part 12 is a die pad for mounting and fixing the vibrator package 30 and has an area and width suitable for the purpose. The island portion 12 includes holding lead portions 13 and 14 that are integrally extended from both side edges. The holding lead portions 13 and 14 have a width narrower than the width of the island portion 12 and are integrated with a support frame (not shown) cut off before completion.

The lead terminal 11 is electrically connected to the IC chip 80 and the vibrator package 30 and also serves to fix the IC chip 80.
That is, as shown in FIGS. 3 and 5, the lead terminal 11 is exposed to the outside of the resin 21, is bent along the outer surface of the piezoelectric oscillator 70, and has a horizontal portion 11 d as a mounting terminal so as not to contact each other. It has a plurality of lead terminals 11b formed. 4 and 5, it is formed so as to pass through a region facing an external terminal portion 31a, 31a on the vibrator package 30 described later, and external terminal portions 31a, 31a and solder (not shown). ) Etc., and has a plurality of lead terminals 11c.

  The number of lead terminals 11 corresponds to the number of terminals of the IC chip 80 connected thereto. That is, each of the plurality of lead terminals 11b and lead terminals 11c is formed with an end portion 11a in the vicinity of the peripheral edge of the IC chip 80 so as not to contact the island portion 12. A plurality of terminal portions 81 and 82 (see FIG. 5) provided on the chip 80 are joined by bumps 15, 15,... (See FIG. 2). In the present embodiment, these bumps 15 are formed of solder or the like, and are formed so that adjacent bumps 15 do not electrically interfere with each other.

Next, the vibrator package 30 fixed to the island portion 12 will be described with reference to FIGS. 1 to 5 and FIG. 6 viewed from the lid side of the vibrator package 30.
In these drawings, the vibrator package 30 can be used alone as a piezoelectric device. In particular, in this embodiment, an example in which a crystal vibrator is configured is shown. The vibrator package 30 houses a piezoelectric vibrating piece 32 in a housing container 36. The container 36 is formed, for example, by laminating a plurality of substrates formed by molding an aluminum oxide ceramic green sheet as an insulating material, and then sintering. Each of the plurality of substrates is formed with a predetermined hole on the inner side thereof so that a predetermined inner space S is formed on the inner side when stacked.
This internal space S is a housing space for housing the piezoelectric vibrating piece.
That is, as shown in FIG. 2, in this embodiment, the storage container 36 is formed by, for example, stacking the first laminated substrate 61, the second laminated substrate 64, and the third laminated substrate 68 from above. Has been.

As shown in FIG. 6, the second laminated substrate 64 that is exposed to the internal space S and forms the inner surface in the vicinity of the left end in the figure in the internal space S of the storage container 36 has, for example, nickel on the tungsten metallization. Electrode portions 31, 31 formed by plating and gold plating are provided.
The electrode portions 31 are connected to the outside to supply a driving voltage. Conductive adhesives 43, 43 are applied on the electrode portions 31, 31, and the base 51 of the piezoelectric vibrating piece 32 is placed on the conductive adhesives 43, 43. 43 are hardened. In addition, as the conductive adhesives 43 and 43, a synthetic resin agent as an adhesive component exhibiting a bonding force and containing conductive particles such as fine silver particles can be used. A system-based or polyimide-based conductive adhesive or the like can be used.

The piezoelectric vibrating piece 32 is formed by etching, for example, quartz as a piezoelectric material. In the case of this embodiment, the piezoelectric vibrating piece 32 is formed in a small size to obtain necessary performance, particularly in FIG. It is set as the shape shown by.
That is, the piezoelectric vibrating reed 32 includes a base 51 fixed to the container 36 side, and a pair of vibrating arms 34 extending parallel to the fork 51 in the right direction in FIG. A so-called tuning fork type piezoelectric vibrating piece having a shape 35 like the tuning fork is used.
Lead electrodes 52 and 53 are formed near both ends in the width direction of the end portion (left end portion in FIG. 6) of the base portion 51 of the piezoelectric vibrating piece 32. The lead electrodes 52 and 53 are similarly formed on the back surface (not shown) of the base 51 of the piezoelectric vibrating piece 32.

  Each of these lead electrodes 52 and 53 is a portion connected to the above-described electrode portions 31 and 31 on the container side by the conductive adhesives 43 and 43. As shown in FIG. 5, the electrode portions 31, 31 on the storage container side include external terminal portions 31 a, 31 a formed on the outer surface of the left end portion of the storage container 36, and casters provided at corners of the storage container 36. Connection 36b, 36b. The lead electrodes 52 and 53 of the piezoelectric vibrating piece 32 are connected to excitation electrodes provided on the vibrating arms 34 and 35 (not shown).

In addition, as shown in FIG. 2, the vibrator package 30 is formed with through holes 37 a and 37 b that are continuous with the two laminated substrates 61 and 64 constituting the container 36, thereby opening the through holes 37 that are opened to the outside. Is provided. Of the two through holes constituting the through hole 37, the outer through hole 37a, which is the second hole, has a larger inner diameter than the first hole 37b that opens inside the package. Yes. Thereby, the through-hole 37 is a stepped opening including an upward stepped portion 62 in FIG.
The metal sealing material 38 filled in the through hole 37 is selected from, for example, silver brazing, Au / Sn alloy, Au / Ge alloy, and the like. Further, a metal coating portion (not shown) is provided on the inner surface of the through-hole 37, and for this metal coating portion, nickel plating and gold plating are used on, for example, tungsten metallized having good wettability with the metal sealing material 38. ing.

And the lid | cover 39 is joined to the open end surface of the container 36 by using brazing material 36a, such as low melting glass, and is sealed. As will be described later, the lid 39 irradiates a metal coating portion of the piezoelectric vibrating piece 32 with a laser beam L2 from the outside and adjusts the frequency by a mass reduction method. It is made of thin glass.
As a material suitable for forming the lid 39 transparently, glass is generally used. As such a glass material, for example, borosilicate glass is used as a thin plate glass manufactured by a downdraw method, for example. Is done.

Next, an IC chip 80 as a semiconductor element will be described with reference to FIGS.
The IC chip 80 accommodates an oscillation circuit formed of an integrated circuit (not shown) inside, and is fixed to one surface (the upper surface in FIG. 2) of the lead frame 10 as described above. That is, the IC chip 80 is provided with several terminal portions 81, 82,... On the joint surface with the lead frame 10, and is formed on the terminal frame 81, 82,. Further, the end portions 11 a of the plurality of lead terminals 11 are joined by bumps 15, respectively. Of course, the number of terminal portions of the IC chip 80 may be larger or smaller than that shown in FIG. 5 depending on the type of the IC chip.

  In this embodiment, in FIG. 5, the terminal portions 81, 81 of the IC chip 80 are called, for example, gate / drain (G / D) terminals and are connection terminals to the vibrator package 30. That is, the terminal portions 81 and 81 are joined to the lead terminals 11c and 11c of the lead frame 10 using the bumps 15, and the lead terminals 11c and 11c are connected to the external terminal portions 31a and 31a by solder or the like. Since the individual configurations of the other terminal portions of the IC chip 80 differ depending on the type of the IC chip 80, the description thereof will be omitted.

The piezoelectric oscillator 70 of the present embodiment is configured as described above, and is resin-molded so that the transparent lid 39 of the vibrator package 30 is exposed to the outside as shown in FIG. Therefore, even after assembly, the transparent lid 39 can be transmitted from the outside, and the laser beam L2 for frequency adjustment can be irradiated inside by the same method as described in FIG. Thereby, after the piezoelectric oscillator 70 is manufactured, the frequency of the piezoelectric vibrating piece 32 in the vibrator package 30 can be adjusted particularly after resin molding.
In other words, after the lid of the vibrator package 30 is sealed, if the frequency of the piezoelectric vibrating piece 32 changes to a problem level due to the influence of a manufacturing process such as a resin mold, the electrodes of the piezoelectric vibrating piece 32 A part or the like is evaporated by the laser beam L2, and the frequency can be adjusted by the mass reduction method.
In addition to the frequency adjustment, it is also possible to cut the wiring in the package that has become unnecessary after manufacturing the product.

Next, an embodiment of a method for manufacturing the piezoelectric oscillator 70 will be described with reference to FIG. 7 which is a flowchart corresponding to a preferred embodiment of the method for manufacturing the piezoelectric oscillator 70 of the present embodiment.
In this embodiment, first, a lead frame is formed (ST1).
That is, as shown in FIG. 8, the lead frame 10 is separated from the support frame 17, the island portion 12 that is a die pad supported by the support frame 17 via the holding lead portions 13 and 14, and the island portion 12. The lead terminals 11 and 11 are supported by the support frame 17 and arranged around the island portion 12 at a predetermined distance and arranged at predetermined intervals. In FIG. 8, the lead frame 10 is shown as a lead frame for manufacturing only one piezoelectric oscillator 70. However, in actuality, the illustrated lead frame 10 is formed so as to be vertically and horizontally connected to the continuous lead frame. On the other hand, the manufacturing method described below is similarly performed.

Next, as shown in FIGS. 9A and 9B, the IC chip 80 and the vibrator package 30 are connected to the lead frame 10 (ST2 and ST3 in FIG. 7). 9A and 9B show the opposite surfaces.
That is, as shown in FIG. 9 (b), bumps made of solder or the like on the end portions 11a, 11a,... Of the lead terminals 11, 11 in FIG. The IC chip 80 is placed so that the bump and the terminal portion (see FIG. 5) of the IC chip 80 face each other, and the bump is melted in a reflow furnace or the like, so that one surface of the lead frame 10 is formed. The lead terminals 11 and 11 and the IC chip 80 are joined and fixed and electrically connected (ST2).

  Further, as shown in FIG. 9A, a portion where the external terminal portion 31a on the bottom surface of the vibrator package 30 is not provided using a non-conductive adhesive, for example, an epoxy or silicone adhesive. Is fixed to the island portion 12 on the other surface of the lead frame 10 (ST3). Further, as shown in FIG. 9B, the vibrator package 30 is placed so that the external terminal portions 31a and 31a face the lead terminal portions indicated by reference numerals 11c and 11c among the lead terminals. At this time, the external terminal portions 31a and 31a and the lead terminals 11c and 11c are electrically and mechanically connected with, for example, solder.

Next, resin molding is performed as shown in FIGS. 10 to 13 (ST4 in FIG. 7).
As shown in FIGS. 11 and 13, molds 18 and 19 are used for this molding. One mold 18 is represented on the lower side of FIGS. 11 and 13, and the other mold 19 is represented on the upper side of FIGS. 11 and 13.
In this step, by moving one mold 18 and / or the other mold 19 relatively in the direction of the arrow as shown in FIG. 11, the holding lead portions 13 and 14 of the lead frame 10 and the lead terminals are moved into the mold. 11 outside the region to be molded with resin. Thus, the vibrator package 30 connected to the island portion 12 and the lead terminal 11c and the IC chip 80 connected to the lead terminal 11b are accommodated, and the molten resin is fed from the gate (not shown) into the combined mold. Is formed by transfer molding. Here, as the mold resin, for example, an epoxy resin can be used.

  In this case, as shown in FIG. 13, the depth D of the lower mold 18 is set to be smaller than the thickness h including the lid 39 of the vibrator package 30. . Then, as shown in FIG. 13, the IC chip 80 and the vibrator package 30 fixed to the island portion 12 and the lead terminal 11 are accommodated between the one mold 18 and the other mold 19. The support frame 17 is sandwiched with reference to the position. That is, the joint between one mold 18 and the other mold 19 is set and sandwiched at positions outside the holding lead portions 13 and 14 and the lead terminal 11 in the region to be resin-molded.

Here, the vibrator package 30 is disposed so that the lid 39 is brought into contact with the inner surface of one of the molds 18 in the mold. In addition, since the depth D of the one mold 18 is made smaller than the thickness h including the lid 39 of the vibrator package 30, the outer surface of the lid 39 is connected to the inner surface of the one mold 18. Strongly pressed. In addition, at least the bonding region fixed to the vibrator package 30 and the IC chip 80 of the lead frame 10 is positioned in a direction away from the transparent lid 39 as compared to other than the bonding region of the lead frame 10. At least a part of the lead frame 10 is deformed. That is, as shown in FIGS. 2 and 13, the holding lead parts 13 and 14 are deformed so that the island part 12 side is directed upward, and as shown in FIG. 3, the lead terminals 11 are outside the mold resin. The end portion 11a of the lead terminal 11 is deformed so as to be directed upward as compared with the plane existing in FIG.
As described above, the vibrator package 30 is displaced upward in the drawing, and the outer surface of the lid 39 is strongly pressed against the inner surface of the one mold 18, so that molten resin is injected into the mold in this state. The molten resin is prevented from flowing between the outer surface of the lid body 39 and the inner surface of the one mold 18, and the resin does not adhere to the outer surface of the lid body 39 after molding.

  Further, as shown in FIG. 11 and FIG. 13, a convex portion 19 a is provided on the inner surface of the other mold 19, which is the opposite mold to the one mold 18 with which the lid 39 is brought into contact with the inner surface. The convex portion 19a has such a length that the lead terminal 11 can be pressed against the bottom surface (the surface opposite to the lid) of the vibrator package 30 when the one mold 18 and the other mold 19 are combined. L. For this reason, even if the stress generated when one mold 18 and the other mold 19 are applied to the lead terminal 11, the portion of the lead terminal 11 pressed by the convex portion 19 a and the vibrator package 30. Prevents deformation.

Moreover, the convex portion 19a of this embodiment is outside the bumps 15, 15,... Provided on the end portion 11a (see FIG. 5) of the lead terminal 11, and these bumps 15, 15,. In the region along the periphery of the IC chip 80 (the region indicated by the parallel oblique lines in FIGS. 10 and 12) so as to surround the periphery of the chip, it extends toward the one mold 18. In this way, in the present embodiment, the bonding state of the IC chip 80 and the lead terminal 11 by the bumps 15 can be better maintained.
Since the molten resin is not injected into the portion of the mold where the convex portion 19a is provided, as shown in FIG. 1, a trace of the convex portion 19a is left on the completed piezoelectric oscillator 70. That is, since the convex portion 19a presses the lead terminal 11 against the vibrator package 30, the resin is not exposed to the pressed portion of the lead terminal 11 and exposed to the outside.

  Next, in a state where the mold is clamped, the coupling with the support frame 17 is cut except for the holding lead portions 13 and 14 as shown in FIG. That is, the outer ends of the lead terminals 11 are cut. Subsequently, terminal plating is applied to the exposed portions of the cut lead terminals 11 and 11 from the mold (ST5 in FIG. 7). Then, as shown in FIG. 14, the outer end portions of the lead terminals 11 and 11 are bent toward the lid 39 using a predetermined jig, and formed into a so-called J lead state (ST6 in FIG. 7). .

As shown in FIG. 15, after the piezoelectric oscillator 70 is formed, that is, after resin molding, the transparent cover 39 exposed to the outside is transmitted, and the laser light L2 is transmitted from the outside to the piezoelectric vibrating piece 32. Irradiate the electrodes. Thereby, a part of metal coating | coated parts, such as an electrode part, is evaporated, and a frequency can be adjusted to a high direction by a mass reduction system (ST7 of FIG. 7). Therefore, the final frequency adjustment can be performed even if the frequency of the vibrator package 30 is changed in any of the manufacturing processes so far, for example, a process involving heat such as a molding process. Therefore, such a frequency shift prevents the product from becoming a defective product, eliminates the waste of parts, and improves the manufacturing yield.
Finally, the piezoelectric oscillator 70 is completed through necessary inspections (ST8 in FIG. 7).

16 and 17 show a piezoelectric oscillator 100 according to a first modification of the embodiment of the present invention. FIG. 16 is a schematic plan view of the piezoelectric oscillator 100, and FIG. 17 is a schematic view taken along line EE of FIG. It is a cut end view.
In these drawings, the portions denoted by the same reference numerals as those used in the description of the piezoelectric oscillator 70 described above have a common configuration, and thus a duplicate description will be omitted, and the following description will focus on the differences.
The piezoelectric oscillator 100 shown in these figures is different from the piezoelectric oscillator 70 shown in FIGS. 1 to 15 in that the convex portion 19a (see FIG. 13) provided on the inner surface of the other mold 19 presses the vibrator package 30. About traces.

That is, in FIGS. 16 and 17, marks 112, 114, 116, and 118 in which the convex portions 19 a (see FIG. 13) provided on the inner surface of the other mold 19 press the vibrator package 30 are shown in FIG. 1. As shown in the trace, the IC chip 80 is not continuously surrounded but formed so as to be interrupted. That is, the resin 21 is also molded between the traces 112, 114, 116, and 118, and the resin 21a attached to the area surrounded by the traces 112, 114, 116, and 118, and the other areas. Communication portions 120, 120, 120, and 120 that integrally connect the adhered resin 21 b are formed.
The communication portions 120 are not arranged on the lead frame 10, and in the first modification, as shown in FIG. Are provided at four locations near the corners in plan view.

Next, a method for manufacturing the piezoelectric oscillator 100 will be described with reference to FIG.
The manufacturing method of the piezoelectric oscillator 100 is different from the manufacturing method described with reference to FIGS. 7 to 15 in that the shape of the convex portion 19a provided on the inner surface of the other mold 19 is different in the mold forming step (ST4 in FIG. 7). It is only the difference.

  That is, as shown in FIG. 18, the convex portion 19 a is formed so as to be interrupted on the inner surface of the other mold 19. Therefore, the resin 21 is filled in the portion where the convex portion 19a is interrupted, and the resin 21 filled in the interrupted portion becomes the communication portion 120 in FIG. Specifically, the convex portions 19 a are formed intermittently so as to press the lead terminals 11, particularly the lead terminals 11 joined to the IC chip 80 by bumps, against the vibrator package 30.

  The first modification according to the embodiment of the present invention is configured as described above, and thus exhibits the same effects as those of the first embodiment. Further, in the first modification, the convex portion 19 a is formed so as to be interrupted on the inner surface of the other mold 19. For this reason, communication portions 120, 120, 120, 120 are formed to integrally connect the resin 21a attached to the region surrounded by the marks 112, 114, 116, 118 and the resin 21b attached to the other regions. Is done. Therefore, the area where the resin 21 around the IC chip 80 is fixed to the piezoelectric oscillator 100 can be increased, and the connection reliability between the IC chip 80 and the lead frame 10 can be improved.

19 and 20 show a second modification of the embodiment of the piezoelectric oscillator of the present invention. FIG. 19 is a schematic plan view when seen through the resin 21, and FIG. It is a general | schematic cut sectional view cut | disconnected in the position of -D line | wire.
In these drawings, the portions denoted by the same reference numerals as those used in the description of the piezoelectric oscillator 70 described above have a common configuration, and thus a duplicate description will be omitted, and the following description will focus on the differences.

In the piezoelectric oscillator 72 of this modification, the external terminal portions 31 a and 31 a of the vibrator package 30 and the so-called gate / drain (G / D) terminals 81 and 81 of the IC chip 80 are bumps without passing through the lead terminals 11, respectively. 92 is directly joined.
The bump 92 is formed by overlapping a plurality of bumps 90 and 91. That is, as shown in FIG. 20, the vibrator package 30 and the IC chip 80 are respectively fixed to different surfaces of the lead frame 10, and the lead frame 10 and the IC chip 80 are joined by the bumps 15. Therefore, the transducer package 30 and the IC chip 80 are separated by at least the height h3 of the bump 15 and the thickness h2 of the lead frame 10 added. For this reason, a plurality of bumps 90 and 91 are formed to overlap each other so that the height can be secured by adding the thickness h2 of the lead frame 10 to the height h3 of the bump 15.

  Specifically, for example, bumps 90 are formed in advance on each of the terminals 81 and 81 of the IC chip 80, and the bumps 91 are opposed to the bumps 90 on each of the external terminal portions 31 a and 31 a of the vibrator package 30. Is formed in advance. Then, as shown in FIG. 7 described above, the IC chip 80 is fixed to the lead frame 10 (ST2 in FIG. 7), and the vibrator package 30 is fixed to the lead frame 10 (ST3 in FIG. 7). Since the bumps 91 are arranged so as to oppose each other, the bumps 90 and the bumps 91 are bonded to each other so that the bump bonding can be surely performed even if the vibrator package 30 and the IC chip 80 are separated.

  Since the piezoelectric oscillator 72 bump-bonds the vibrator package 30 and the IC chip 80, the IC chip 80 is connected to the lead terminal 11c and the external terminal in the mold forming step (ST4) of FIG. Compared with the case where the part 31a is soldered with a large area, the part 31a is easily peeled off, and the bump 92 and the bump 15 are easily damaged. For this reason, in the mold forming step (ST4) of FIG. 7, the convex portions 19a provided on the inner surface of the other mold 19 shown in FIG. 11 are bumps 92 for joining the vibrator package 30 and the IC chip 80, and the lead terminals 11. And the bump 15 that joins the IC chip 80 are formed so as to surround the periphery.

The second modified example of the present embodiment is configured as described above. Therefore, the same function and effect as those of the embodiments of FIGS. 1 to 15 are exhibited, and further, the vibrator package 30, the IC chip 80, In combination with the bump 92 and the lead terminal 11 and the IC chip 80 joined with the bump, the generation of parasitic capacitance is effectively prevented.
Further, when the vibrator package 30 is fixed to the lead frame 10, the vibrator package 30 and the IC chip 80 are joined by the bumps 92, so that the vibrator package 30 and the IC chip 80 are wire-bonded. A process becomes unnecessary and manufacture of the piezoelectric oscillator 72 becomes easy.

  The present invention is not limited to the above-described embodiment. Each configuration of the embodiment and each modified example can be appropriately combined or omitted, and can be combined with other configurations not shown.

1 is a schematic plan view showing an embodiment of a piezoelectric oscillator of the present invention. FIG. 2 is a schematic sectional view taken along line AA in FIG. 1. FIG. 2 is a schematic sectional view taken along line BB in FIG. 1. FIG. 2 is a schematic cross-sectional view taken along line CC of FIG. 1. The schematic plan view at the time of seeing through resin of the embodiment of the piezoelectric oscillator of the present invention. Schematic view seen from the lid side of the vibrator package. The flowchart which shows simply an example of the manufacturing process of the piezoelectric oscillator of FIG. FIG. 8 is a schematic plan view showing an example of a lead frame prepared in the manufacturing process of FIG. 7. It is the schematic which shows a part of manufacturing process of FIG. 7, (a) is a schematic bottom view, (b) is a schematic plan view. FIG. 8 is a schematic plan view showing a part of the manufacturing process of FIG. 7. FIG. 11 is a schematic cross-sectional view showing the mold before clamping in the step of FIG. 10. FIG. 8 is a schematic plan view showing a part of the manufacturing process of FIG. 7. FIG. 13 is a schematic cross-sectional view showing the mold after clamping in the step of FIG. 12. FIG. 8 is a schematic cross-sectional view showing a part of the manufacturing process of FIG. 7. FIG. 8 is a schematic cross-sectional view illustrating a frequency adjustment process in the manufacturing process of FIG. 7. The schematic plan view of the piezoelectric oscillator which concerns on the 1st modification of embodiment of this invention. FIG. 17 is a schematic cut end view taken along the line EE of FIG. 16. The figure for demonstrating the characteristic part about the manufacturing method of the piezoelectric oscillator which concerns on the 1st modification of embodiment of this invention. The schematic plan view at the time of seeing the 2nd modification which concerns on embodiment of the piezoelectric oscillator of this invention, and seeing through resin. FIG. 20 is a schematic cross-sectional view cut along the line D-D in FIG. 19. FIG. 6 is a schematic cross-sectional view showing an example of a conventional piezoelectric oscillator.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Lead frame, 11 ... Lead terminal, 12 ... Island part, 13, 14 ... Holding lead part, 15, 90, 91, 92 ... Bump, 21 ... Resin, 30 ... vibrator package, 32 ... piezoelectric vibrating piece, 39 ... lid, 70, 72 ... piezoelectric oscillator, 80 ... IC chip (semiconductor element)

Claims (9)

A vibrator package containing a piezoelectric vibrating piece inside;
It has a semiconductor element with a built-in oscillation circuit that is electrically connected to this vibrator package,
The vibrator package and the semiconductor element are respectively fixed to different surfaces of the lead frame,
Resin molded so that the transparent lid of the vibrator package is exposed to the outside,
A lead oscillator of the lead frame is joined to the semiconductor element by a bump.   The piezoelectric oscillator according to claim 1, wherein the vibrator package and the semiconductor element are joined by a bump.   The piezoelectric oscillator according to claim 2, wherein the bump that joins the vibrator package and the semiconductor element is formed by overlapping a plurality of bumps.   The bonding region fixed to at least the vibrator package and the semiconductor element of the lead frame is positioned in a direction away from the transparent lid, as compared to other than the bonding region of the lead frame. 4. The piezoelectric oscillator according to claim 1, wherein at least a part of the lead frame is deformed. A lead frame including a support frame that integrally supports an outer end of a plurality of lead terminals and an outer end of a holding lead portion extending from an island portion serving as a die pad is prepared,
A step of bonding and fixing a semiconductor element containing an oscillation circuit to the lead terminal on one surface of the lead frame by a bump;
Fixing a vibrator package to the island portion on the other surface of the lead frame;
And a step of resin molding the semiconductor element and the vibrator package such that a transparent lid of the vibrator package is exposed.   6. The method of manufacturing a piezoelectric oscillator according to claim 5, wherein, in the step of fixing the vibrator package, the vibrator package and the semiconductor element are bonded with bumps.   In the resin molding step, the transparent lid is one mold for molding, the depth of which is in contact with the inner surface of the mold smaller than the thickness of the vibrator package, and the position of the support frame is used as a reference Then, by combining the one mold and the other mold, at least a part of the lead frame is deformed so that the transparent lid is displaced inward within the mold. A method for manufacturing a piezoelectric oscillator according to claim 5 or 6.   In the resin molding step, a convex portion is provided on the inner surface of the other mold, and the one mold and the other mold are combined while pressing the lead terminal against the vibrator package by the convex section. A method for manufacturing a piezoelectric oscillator according to claim 7.   9. The method of manufacturing a piezoelectric oscillator according to claim 8, wherein the convex portion is formed so as to be interrupted on an inner surface of the other mold.

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