JP2007180900A - Crystal oscillator and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To relax an impact applied to a crystal resonator by absorbing an impact transmitted from a semiconductor device to the crystal resonator by an impact absorbing means. <P>SOLUTION: The crystal oscillator includes a crystal resonator 10 provided with a connection terminal 5 connected to a pair of electrodes 21 and 22 for voltage application and a semiconductor device 20 which has a connection terminal 60 conductive to the connection terminal 4 of the crystal resonator 10 and drives the crystal resonator 10. An impact absorbing means 80 which secures conduction between the connection terminal 4 of the crystal resonator 10 and the connection terminal 60 of the semiconductor device 20 and absorbs a impact transmitted from the semiconductor device 20 to the crystal resonator 10 is provided between the crystal resonator 10 and the semiconductor device 20. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a crystal oscillator and a manufacturing method thereof.

Conventionally, as a crystal resonator, for example, a structure in which a resonator piece provided with a pair of voltage application electrodes is sealed with glass is known (see, for example, Patent Document 1).
For example, such a crystal resonator is used as a crystal oscillator by being combined with a semiconductor device (semiconductor device).

By the way, when manufacturing a crystal oscillator, the crystal resonator and the semiconductor device are joined after the connection terminal of the crystal resonator and the connection terminal of the semiconductor device are made conductive. Specifically, for example, the crystal resonator and the semiconductor device are bonded by bonding the connection terminal of the crystal resonator and the connection terminal of the semiconductor device by alloy bonding using solder.
Japanese Patent No. 3390348

However, as described above, when the connection terminal of the crystal resonator and the connection terminal of the semiconductor device are bonded by solder alloy bonding, the crystal resonator and the semiconductor device are rigidly bonded.
For this reason, for example, an impact coming from the side of the semiconductor device directly mounted on the substrate is directly transmitted to the crystal resonator.
Quartz resonators are particularly vulnerable to impacts. For this reason, when an impact is directly transmitted to the crystal unit, the characteristics of the crystal unit may change, and the crystal oscillator may not operate normally.

  The present invention has been made in view of the above-described problems, and an object thereof is to alleviate an impact applied to a crystal resonator.

  In order to achieve the above object, the present invention provides a crystal resonator including a connection terminal connected to each of a pair of voltage application electrodes provided on a resonator element, and the connection terminal of the crystal resonator. A crystal oscillator having a connection terminal to be conducted and a semiconductor device for driving the crystal resonator, the connection terminal of the crystal resonator and the semiconductor device between the crystal resonator and the semiconductor device And an impact absorbing means for absorbing an impact transmitted from the semiconductor device to the crystal resonator.

According to the present invention having such a feature, the shock absorbing means is provided between the crystal resonator and the semiconductor device, and the shock transmitted from the semiconductor device to the crystal resonator is absorbed by the shock absorbing means, and the crystal vibration The connection between the child connection terminal and the semiconductor device connection terminal is ensured.
Then, the impact applied to the crystal resonator can be reduced by absorbing the impact transmitted from the semiconductor device to the crystal resonator by the impact absorbing means.

Specifically, it is possible to adopt a configuration in which the impact absorbing means is a gold bump having a thickness capable of absorbing an impact transmitted from the semiconductor device to the crystal resonator.
In addition, the shock absorbing means may be a resin core bump including a resin core capable of absorbing a shock transmitted from the semiconductor device to the crystal resonator and a conductive layer formed around the resin core. You can also.
The shock absorbing means includes a conductive portion that connects the connection terminal of the crystal resonator and the connection terminal of the semiconductor device, and a resin layer formed between the semiconductor device and the crystal resonator. It is also possible to adopt a configuration of having.
Moreover, the structure that the said impact-absorbing means is an anisotropic conductive film is also employable.

  Next, the present invention provides a crystal resonator including a connection terminal connected to each of a pair of voltage application electrodes provided on the resonator element, and a connection terminal electrically connected to the connection terminal of the crystal resonator And a semiconductor device that drives the crystal resonator, and ensures electrical connection between the connection terminal of the crystal resonator and the connection terminal of the semiconductor device. And a step of bonding the crystal unit and the semiconductor device through an impact absorbing unit that absorbs an impact transmitted to the crystal unit.

  According to the present invention having such characteristics, the crystal resonator and the semiconductor device are joined via the shock absorbing means. The shock absorbing means secures conduction between the connection terminal of the crystal resonator and the connection terminal of the semiconductor device and absorbs an impact transmitted from the semiconductor device to the crystal resonator. Accordingly, it is possible to manufacture a crystal oscillator capable of reducing the impact applied to the crystal resonator by absorbing the impact transmitted from the semiconductor device to the crystal resonator.

  Hereinafter, an embodiment of a crystal oscillator and a manufacturing method thereof according to the present invention will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member a recognizable size.

(First embodiment)
FIG. 1 is a cross-sectional view showing a schematic configuration of the crystal oscillator S1 of the present embodiment.
As shown in FIG. 1, the crystal oscillator S <b> 1 of the present embodiment includes a crystal resonator 10 and a semiconductor device 20.

The crystal resonator 10 includes a resonator element 2 on which a pair of voltage application electrodes 21 and 22 are formed, a package 3, and a connection terminal 4.
The package 3 includes an upper part 32 positioned on the upper side of the vibrator piece 2 and a lower side part 31 located on the lower side of the vibrator piece 2. The package 3 is made of glass. The vibrator element 2 is sandwiched between the upper part 32 of the package 3 and the lower part 31 of the package 3.
In addition, a bonding layer 5 made of metal is formed between the vibrator element 2 and the package 3. In FIG. 1, voltage application electrodes 21 and 22 are shown between the vibrator element 2 and the lower portion 31 of the package 3, but there are no voltage application electrodes 21 and 22. In the portion, a bonding layer 5 made of metal is formed between the vibrator element 2 and the lower side portion 31 of the package 3. The vibrator piece 2 and the package 3 are bonded together by anodic bonding using the bonding layer 5.
That is, the vibrator element 2 is disposed between the upper part 32 of the package 3 and the lower part 31 of the package 3, and the upper part 32, the package 3, and the lower part 31 are bonded via the bonding layer 5. Are combined.
With such a configuration, the vibrator element 2 is sealed by the package 3.

As shown in FIG. 1, missing portions 7 are formed on both sides of the lower portion 31 of the package 3. The missing portion 7 is formed up to the upper surface 313 of the lower portion 31 so that the voltage applying electrodes 21 and 22 of the vibrator piece 2 are exposed.
In addition, as shown in FIG. 1, the wall surface 71 of the missing part 7 is formed to be inclined.

  The connection terminal 4 is formed so as to be connected to the voltage application electrodes 21 and 22 of the vibrator element 2 from the lower surface 311 of the lower side portion 31 of the package 3 through the wall surface 71 of the missing portion 7. More specifically, one connection terminal 41 is formed to be connected to the voltage application electrode 21, and the other connection terminal 42 is formed to be connected to the voltage application electrode 22.

  The semiconductor device 20 has a rectangular shape in plan view, and is mounted with the active surface 30 side as the outer surface side. In this semiconductor device 20, an integrated circuit (not shown) made of a semiconductor element such as a transistor or a memory element is formed on the active surface 30 side of the silicon substrate 40, and the active surface 30 faces the outer surface side. The external connection terminal 50 is formed on the side.

  The semiconductor device 20 has a through electrode 60 (connection terminal). The through electrode 60 is formed so as to be electrically connected to the integrated circuit on the active surface 30 side of the silicon substrate 40 and further penetrate from the active surface 30 side to the back surface side thereof.

Then, the crystal resonator 10 having such a configuration and the semiconductor device 20 are joined via a gold bump 80 (impact absorbing means).
As shown in FIG. 1, the gold bump 80 is placed in contact with the connection terminal 4 of the crystal resonator 10 and the through electrode 60 of the semiconductor device 20. Thereby, conduction between the connection terminal 4 of the crystal resonator 10 and the through electrode 60 of the semiconductor device 20 is ensured.
Further, the thickness of the gold bump 80 is set to absorb the impact transmitted from the semiconductor device 20 side to the crystal resonator 10. Specifically, the gold bump 80 has a thickness of 20 to 30 μm.

  The crystal oscillator S1 of this embodiment having such a configuration is mounted on a circuit board or the like via an external connection terminal 50 formed in the semiconductor device 20. Then, the drive voltage from the semiconductor device 20 is applied to the voltage application electrodes 21 and 22 of the resonator element 2 through the gold bump 80 and the connection terminal 4, thereby driving the crystal resonator 10.

  According to the crystal oscillator S1 of this embodiment as described above, the impact transmitted from the semiconductor device 20 to the crystal resonator 10 is absorbed by the gold bump 80. For this reason, the impact applied to the crystal unit 10 can be reduced.

  Next, a manufacturing method of the crystal oscillator S1 of the present embodiment will be described with reference to FIGS.

  First, a method for manufacturing the crystal unit 10 will be described. Since the crystal unit is manufactured with the crystal unit illustrated in FIG. 1 turned upside down, in FIGS. 2 to 6, the crystal unit is illustrated upside down with respect to FIG. 1.

As shown in FIG. 2, a quartz substrate 100 in which a plurality of vibrator pieces 2 are formed at a predetermined interval, an upper glass substrate 200 in which a plurality of upper portions 32 of the package 3 are formed, and a plurality of lower portions 31 in the package 3 are provided. A formed lower glass substrate 300 is prepared. The crystal substrate 100 is formed with an electrode layer 23 that becomes a pair of voltage application electrodes 21 and 22 by being cut by later dicing.
Further, the vibrator piece 2, the upper part 32, and the lower part 31 are arranged at the same predetermined interval on each substrate. For this reason, the quartz crystal substrate 100, the upper glass substrate 200, and the lower glass substrate 300 are overlapped, whereby the vibrator piece 2 of each substrate, the upper portion 32 of the package 3, and the lower portion 31 of the package 3 are formed. overlap.

  Next, as shown in FIG. 3, a plurality of openings 500 are formed in the lower glass substrate 300 by blasting, etching, or the like. The opening 500 is a portion that becomes the missing portion 7 after dicing. The opening 500 is formed in accordance with the position of the electrode layer 23 (the voltage application electrodes 21 and 22 provided on the vibrator element 2) of the quartz crystal substrate 100.

Subsequently, as shown in FIG. 4, the upper glass substrate 200 is bonded to one surface 101 of the crystal substrate 100, and the lower glass substrate 300 is bonded to the other surface 102 of the crystal substrate.
Specifically, after the material of the bonding layer 5 is disposed between the substrates, the upper glass substrate 200, the quartz substrate 100, and the lower glass substrate 300 are overlapped in this order from the lower side, and the upper side is formed using the bonding layer 5. The glass substrate 200, the quartz substrate 100, and the lower glass substrate 300 are joined by anodic bonding.
Thus, each vibrator piece 2 is sealed by bonding the upper glass substrate 200, the quartz substrate 100, and the lower glass substrate 300 by anodic bonding.

Then, as shown in FIG. 5, a conductive thin film 600 is collectively formed on the surface of the lower glass substrate 300 by, for example, sputtering or plating.
Here, the opening part 500 corresponding to each electrode layer 23 is formed in the lower glass substrate 300. Therefore, each conductive thin film 600 is formed to be connected to the electrode layer 23 via the inner wall surface 501 of the opening 500.

Subsequently, as shown in FIG. 6, the crystal substrate 100, the upper glass substrate 200, and the lower glass substrate 300 are separated by the cutting process by the dicing blade 700 while the vibrator element 2 is sealed (dicing).
When dicing, the opening 500 is divided into two parts, whereby the conductive thin film 600 attached to the inner wall surface 501 on one side of the divided opening 500 is used as the connection terminal 41. The conductive thin film 600 attached to the inner wall surface 501 on the other side of the opening 500 is used as the connection terminal 42. In addition, when dicing, the electrode layer 23 is divided into two parts, so that one side of the two-divided electrode layer 23 becomes the voltage application electrode 21, and the other side of the two-divided electrode layer 23 is the voltage application electrode. 22.

The crystal unit 10 is manufactured through the above steps.
Subsequently, a process of forming the through electrode 60 in the semiconductor device 20 will be described.

  First, as shown in FIG. 7, a silicon substrate 40 is prepared. Then, an insulating layer 91 made of silicon oxide is formed on the entire surface of the silicon substrate 40 by thermal oxidation or the like. Next, the resist applied on the insulating layer 91 is patterned into a predetermined shape by exposure and development processes, and a plurality of circular grooves 92 in plan view are formed on the silicon substrate 40 by etching using the resist as a mask.

Then, an insulating layer 91 that covers the inner wall surface of the groove 92 formed on the silicon substrate 40 is formed by a thermal oxidation method or the like, and thereafter, an active surface of the silicon substrate 40 including the inside of the groove 92 is formed by a sputtering method, a vacuum evaporation method, or the like. An underlayer 93 is formed.
Next, as shown in FIG. 8, a plating resist is applied on the active surface 30 of the silicon substrate 40, and the plating resist is further applied to an opening 94 a (from the opening diameter of the groove 92) where the silicon substrate 40 around the groove 92 is exposed. And a plating resist pattern 94 is formed.

  Subsequently, Cu electrolytic plating is performed using the plating resist pattern 94 as a mask to deposit Cu in the groove 92 including the opening 94a. As a result, the inside of the groove 92 is filled with Cu, and the metal terminal 95 is formed in the opening 94 a including the groove 92. Next, a bonding material 96 made of a brazing material such as lead-free solder is formed on the metal terminal 95 using the plating resist pattern 94 as a mask.

Subsequently, the plating resist pattern 94 is removed from the silicon substrate 40 by ashing. Thereafter, as shown in FIG. 9, the silicon substrate 40 is back-ground from the back surface 90 side (the bottom surface in the drawing), and the metal terminals 95 are exposed on the back surface 90 of the silicon substrate 40.
Thereby, a plurality of through electrodes 60 made of the metal terminals 95 and the bonding material 96 can be formed in the semiconductor device 20.

Next, the crystal resonator 10 formed as described above and the semiconductor device 20 on which the through electrode 60 is formed are bonded via the gold bump 80.
Specifically, as shown in FIG. 10, gold bumps 80 are formed on the connection terminals 4 of the crystal resonator 10 by using, for example, a stud bump method. Thereafter, the through electrode 60 of the semiconductor device 20 is brought into contact with and joined to the gold bump 80.
Through the above steps, the crystal oscillator S1 of the present embodiment is manufactured.

  Thus, according to the manufacturing method of the crystal oscillator of this embodiment, it becomes possible to manufacture the crystal oscillator that can reduce the impact applied to the crystal resonator 10.

  In the crystal oscillator manufacturing method of the present embodiment, the crystal resonator 10 and the semiconductor device 20 are bonded after the crystal resonator 10 is individualized by dicing. However, the gold resonator 80 may be formed and the semiconductor device 20 may be bonded before the crystal resonator 10 is individualized, and then the crystal resonator 10 may be individualized by dicing.

  Further, in the crystal oscillator and the manufacturing method thereof according to the present embodiment, a resin layer may be formed between the crystal resonator 10 and the semiconductor device 20. By forming the resin layer in this way, it is possible to further reduce the impact transmitted to the crystal unit 10.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the description of the second embodiment, the description of the same parts as in the first embodiment will be omitted or simplified.

FIG. 11 is a cross-sectional view showing a schematic configuration of the crystal oscillator S2 of the present embodiment. As shown in this figure, the crystal oscillator S2 of this embodiment includes a resin core bump 110 (impact absorbing means) instead of the gold bump 80 provided in the crystal oscillator S1 of the first embodiment.
The resin core bump 110 includes a resin core 111 capable of absorbing an impact transmitted from the semiconductor device 20 to the crystal resonator 10 and a conductive layer 112 formed around the resin core 111.
The conductive layer 112 of the resin core bump 110 ensures conduction between the connection terminal 4 of the crystal resonator 10 and the through electrode 60 of the semiconductor device 20, and the resin core 111 of the resin core bump 110 causes the crystal resonator from the semiconductor device 20. The impact transmitted to 10 is absorbed.

  Also in the crystal oscillator S2 of the present embodiment having such a configuration, the impact transmitted from the semiconductor device 20 to the crystal resonator 10 can be mitigated, similarly to the crystal oscillator S1 of the first embodiment.

(Third embodiment)
Next, a third embodiment of the present invention will be described. In the description of the third embodiment, the description of the same parts as those of the first embodiment will be omitted or simplified.

FIG. 12 is a cross-sectional view showing a schematic configuration of the crystal oscillator S3 of the present embodiment. As shown in this figure, the crystal oscillator S3 of the present embodiment includes a solder bump 120 (conductive portion) and a resin layer 130 instead of the gold bump 80 provided in the crystal oscillator S1 of the first embodiment. Yes.
The solder bumps 120 ensure electrical continuity between the connection terminals 4 of the crystal unit 10 and the through electrodes 60 of the semiconductor device 20, and the resin layer 130 absorbs the impact transmitted from the semiconductor device 20 to the crystal unit 10. .

Also in the crystal oscillator S3 of the present embodiment having such a configuration, the impact transmitted from the semiconductor device 20 to the crystal resonator 10 can be reduced as in the crystal oscillator S1 of the first embodiment.
In the present embodiment, the shock absorbing means of the present invention is constituted by the solder bump 120 and the resin layer 130.
Further, in the present invention, what secures conduction between the connection terminal 4 of the crystal resonator 10 and the through electrode 60 of the semiconductor device 20 is not limited to the solder bump 120, and any conductive material can be used.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. In the description of the fourth embodiment, the description of the same parts as those of the first embodiment will be omitted or simplified.

FIG. 13 is a cross-sectional view showing a schematic configuration of the crystal oscillator S4 of the present embodiment. As shown in this figure, the crystal oscillator S4 of the present embodiment includes an anisotropic conductive film 140 (impact absorbing means) instead of the gold bump 80 provided in the crystal oscillator S1 of the first embodiment. .
Then, the conductive fine particles contained in the anisotropic conductive film 140 ensure conduction between the connection terminal 4 of the crystal unit 10 and the through electrode 60 of the semiconductor device 20, and the resin layer of the anisotropic conductive film 140 The impact transmitted from the semiconductor device 20 to the crystal unit 10 is absorbed.

  Also in the crystal oscillator S4 of the present embodiment having such a configuration, the impact transmitted from the semiconductor device 20 to the crystal resonator 10 can be reduced as in the crystal oscillator S1 of the first embodiment.

  The preferred embodiments of the crystal oscillator and the method for manufacturing the same according to the present invention have been described above with reference to the accompanying drawings. Needless to say, the present invention is not limited to the above-described embodiments. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the above embodiment, the crystal oscillator including the crystal resonator having the package 3 made of glass has been described. However, the present invention is not limited to this, and may be a crystal oscillator including a crystal resonator having a package made of silicon, for example.

It is sectional drawing which shows schematic structure of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the crystal oscillator which is 1st Embodiment of this invention. It is sectional drawing which shows schematic structure of the crystal oscillator which is 2nd Embodiment of this invention. It is sectional drawing which shows schematic structure of the crystal oscillator which is 3rd Embodiment of this invention. It is sectional drawing which shows schematic structure of the crystal oscillator which is 4th Embodiment of this invention.

Explanation of symbols

S1 to S4... Crystal oscillator, 10... Crystal resonator, 20... Semiconductor device, 2... Vibrator piece, 21 and 22. Electrode for voltage application, 23. ...... Lower side, 32 ... Upper side, 4, 41, 42 ... Connection terminal, 60 ... Penetration electrode (connection terminal), 80 ... Gold bump, 110 ... Resin core bump, 111 ... Resin core, 112 ... conductive layer, 120 ... solder bump (conductive part), 130 ... resin layer, 140 ... anisotropic conductive film

Claims (6)

A crystal resonator having a connection terminal connected to each of a pair of voltage application electrodes provided on the resonator element, and a crystal resonator having a connection terminal electrically connected to the connection terminal of the crystal resonator A crystal oscillator comprising: a semiconductor device for driving
Shock absorption for securing conduction between the connection terminal of the crystal resonator and the connection terminal of the semiconductor device between the crystal resonator and the semiconductor device and absorbing an impact transmitted from the semiconductor device to the crystal resonator A crystal oscillator comprising means. 2. The crystal oscillator according to claim 1, wherein the impact absorbing means is a gold bump having a thickness capable of absorbing an impact transmitted from the semiconductor device to the crystal resonator. The shock absorbing means is a resin core bump including a resin core capable of absorbing an impact transmitted from the semiconductor device to the crystal resonator and a conductive layer formed around the resin core. The crystal oscillator described. The shock absorbing means includes a conductive portion that connects the connection terminal of the crystal resonator and the connection terminal of the semiconductor device, and a resin layer formed between the semiconductor device and the crystal resonator. The crystal oscillator according to claim 1. 2. The crystal oscillator according to claim 1, wherein the shock absorbing means is an anisotropic conductive film. A crystal resonator having a connection terminal connected to each of a pair of voltage application electrodes provided on the resonator element, and a crystal resonator having a connection terminal electrically connected to the connection terminal of the crystal resonator A method of manufacturing a crystal oscillator comprising a semiconductor device for driving
The crystal resonator and the semiconductor device are connected to each other through shock absorbing means that secures conduction between the connection terminal of the crystal resonator and the connection terminal of the semiconductor device and absorbs an impact transmitted from the semiconductor device to the crystal resonator. A method for manufacturing a crystal oscillator, comprising the step of bonding:

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