JP2010114582A - Method of manufacturing electronic component - Google Patents

Abstract

A method of manufacturing an electronic component in which vacuuming is performed through a through-hole 20 formed in a container and the through-hole 20 is sealed with a sealing body 40 so that a sealing operation can be easily and quickly performed. To provide.
A through hole 20 is provided in the case body 11 to communicate a storage space 16 of a crystal resonator 10 partitioned by a case body 11 and a lid body 12 and an external atmosphere. The sealing body 40 in which the through hole 41 is formed is disposed in the through hole 20 to close the through hole 20. Next, evacuation is performed through the through hole 41 to depressurize the storage space 16. Thereafter, the sealing body 40 is dissolved to close the through holes 20.
[Selection] Figure 8

Description

  The present invention relates to a method for manufacturing an electronic component, and more particularly to a technique for hermetically sealing an electronic component.

  The piezoelectric vibrator that is the electronic component main body is one that stabilizes the vibration characteristics by oscillating in a vacuum atmosphere. For example, in an atmosphere that inhibits vibration such as air, the vibration of the piezoelectric vibrator is affected by the atmosphere, The vibration characteristics may change. By the way, as a method of packaging the piezoelectric vibrator, a ceramic package method in which a piezoelectric vibrator is placed on a case body such as ceramic and a lid is sealed, or three silicon substrates, that is, a silicon substrate for a lid, There is a CSP method (chip scale package method) in which a silicon substrate for an element and a silicon substrate for a base are bonded to each other, a piezoelectric vibrator is accommodated, and then diced into individual piezoelectric vibrators.

  In the ceramic package method, the case body is covered while venting the air in the storage space in which the piezoelectric vibrator is stored. Therefore, it is difficult to make the storage space in a high vacuum state (low atmospheric pressure state), and the CSP method. In this method, since it is difficult to correct errors such as misalignment in a vacuum atmosphere when bonding silicon substrates, bonding is performed in the atmosphere. It will not be.

  Therefore, in Patent Document 1 and Patent Document 2, a through hole is provided in the base, and the housing space of the piezoelectric vibrator is set in a vacuum state. In this vacuum state, a sealing body is disposed in the through hole and heated and dissolved. A piezoelectric vibrator that performs hermetic sealing is described. The reason for placing the sealing body in the through hole in a vacuum state is that if the sealing body is placed in the through hole before evacuation, the through hole is blocked or suction is performed through a narrow gap between the through hole and the sealing body. This is because vacuuming cannot be performed or a long time is required. However, it is not easy to place the sealing body in the through-hole in a vacuum state, but it is a laborious and time-consuming operation, and it is clear that the production efficiency of the piezoelectric vibrator is adversely affected.

JP-A-2005-229340 JP2003-158439

  The present invention has been made based on such circumstances, and is evacuated through a through hole formed in a container housing an electronic component body, and is sealed when the through hole is sealed with a sealing body. An object of the present invention is to provide a method for manufacturing an electronic component that can be easily and quickly stopped.

The method for manufacturing an electronic component of the present invention includes:
In a method of manufacturing an electronic component in which an electronic component main body is provided in a vacuum-tight airtight container,
A step of positioning a sealing body in which a through-hole for vacuuming is formed in a through-hole formed in a container in which an electronic component main body is stored;
Next, a process of evacuating the inside of the container by setting the atmosphere in which the container is placed to a vacuum atmosphere,
Then, the process of melt | dissolving a sealing body and sealing the said through-hole is characterized by including.
Further, a plurality of through holes may be formed in the sealing body, and the plurality of through holes may be orthogonal to each other.

In addition, the method of manufacturing the electronic component of the present invention includes
In a method of manufacturing an electronic component in which an electronic component main body is provided in a vacuum-tight airtight container,
A step of positioning a spherical sealing body in a square-shaped through hole formed in a container in which an electronic component main body is stored;
Next, a process of evacuating the inside of the container by setting the atmosphere in which the container is placed to a vacuum atmosphere,
Then, the process of melt | dissolving a sealing body and sealing the said through-hole is characterized by including.

  Further, the through hole may have a hole on the back side smaller than the outside, and when the sealing body is positioned in the through hole, a gap of 30 μm or more is formed between them. In this way, both shapes may be set.

In addition, the method of manufacturing the electronic component of the present invention includes
In a method of manufacturing an electronic component in which an electronic component main body is provided in a vacuum-tight airtight container,
A step of positioning the sealing body in the through hole of the container in which the electronic component main body is housed and the through hole in which the hole becomes smaller toward the back side from the outer surface is formed;
Next, a process of evacuating the inside of the container by setting the atmosphere in which the container is placed to a vacuum atmosphere,
Then, the step of dissolving the sealing body and sealing the through hole,
One of the cross section of the sealing body and the cross section of the through hole is circular and the other is square.
In addition, a sealing auxiliary layer that is compatible with the sealing body may be formed in the through hole of the container.

  The present invention is evacuated through a through-hole formed in a container containing an electronic component main body, and when the through-hole is sealed with a sealing body, a through-hole is formed in the sealing body. The inside of the container can be quickly evacuated through the through hole while the body is positioned in the through hole. In another invention, since the container has a rectangular through-hole and the sealing body is spherical, the inside of the container can be quickly evacuated through the gap between the two while the sealing body is positioned in the through-hole. In yet another invention, the through hole is formed so that the hole becomes smaller toward the back side, and one of the cross section of the sealing body and the cross section of the through hole is circular and the other is square. Is positioned in the through-hole without passing through the through-hole, and a gap is formed between the two in this state, so that the inside of the container can be quickly evacuated through the gap. Accordingly, in any of the inventions, since the handling of the sealing body can be performed outside the vacuum container before evacuation, the handling of the sealing body is facilitated.

  An embodiment of a method for manufacturing an electronic component according to the present invention will be described. First, a structure that is in the process of manufacturing an electronic component will be described. In FIG. 1A, reference numeral 10 denotes a piezoelectric vibrator, for example, a crystal vibrator, which is an electronic component main body, and reference numerals 11 and 12 denote a case body and a lid body that form containers for housing the crystal vibrator 10 respectively. The case body 11 is made of, for example, a ceramic material, and the crystal resonator 10 can be placed inside the case body 11. A pair of internal electrodes 14a and 14b are formed on the bottom surface 13 of the case body, and these internal electrodes 14a and 14b are external electrodes provided at the lower part of the case body 11 via wiring inside the case body 11 (not shown). 15 is connected.

  Further, as shown in FIGS. 1 and 2, through holes 20 are formed at one corner of the bottom surface 13 of the case body 11 by etching. The through hole 20 may be provided at the center of the bottom surface 13 of the case body 11 or may be provided at a plurality of locations as well as at one location. As shown in FIG. 1A, the longitudinal cross-sectional shape of the through hole 20 is formed so that the hole diameter becomes narrower from the outer surface side to the inner surface side of the case body 11. The cross-sectional shape of the through hole 20 is a square shape due to the characteristics of quartz, for example, a hexagonal shape in FIG. 1B, but it can also be formed into a circular shape by a physical force by press working or the like. In addition, a metal layer 21 is formed on the surface of the through hole 20, and for example, a gold tin alloy (AuSn), a gold germanium alloy (AuGe), a gold silicon alloy (AuSi), or the like is used as the metal layer 21. The metal layer 21 forms a sealing auxiliary layer, and a material that is easily compatible with the sealing body when the sealing body described later is dissolved is used. A metal having a melting point lower than that of the case body 11 is used for the metal layer 21 and the sealing body. The through-hole 20 has a role of disposing a sealing body in the through-hole 20 and making the storage space of the crystal unit 10 a vacuum atmosphere through the through-hole 20 and the sealing body.

  The lid body 12 constituting a part of the container is fixed to the case body 11 by seam welding to the upper surface of the side wall of the case body 11 via a sealing material made of, for example, a welding material. A space defined by the bottom surface of the lid 12 and the inner surface and the bottom surface of the case body 11 is formed as a storage space 16 for the crystal resonator 10.

  In the crystal unit 10, excitation electrodes 31a and 31b are formed on both surfaces of a crystal piece 30, and the excitation electrodes 31a and 31b are provided on the front and back surfaces through the side surfaces of the crystal piece 30 as shown in FIG. Are connected to lead electrodes 32a and 32b formed across the gate. Since the lead electrodes 32a and 32b are electrically connected to the internal electrodes 14a and 14b via the conductive adhesive 33, the crystal resonator 10 is held in a state of being fixed to the bottom surface 13. In other words, it is stored in the storage space 16. Note that a tuning fork type crystal resonator having a pair of vibrating arms may be used as the crystal resonator 10 used in the present embodiment.

  Next, the sealing body 40 is demonstrated using FIG. The sealing body 40 has a role of sealing the storage space 16 by being melted by heating and closing the through hole 20 together with the metal layer 21. As shown in FIG. 3A, the sealing body 40 is, for example, a true sphere, and the size thereof is set to a size that allows about half of the sphere to enter the through hole 20. Further, the true spherical sealing body 40 has a through-hole 41 for evacuation, which serves as an air vent when the housing space 16 is evacuated, in the radial direction. Here, since the through hole 20 is narrowed toward the back side from the outer surface, if there is one through hole 41, the storage space 16 and the external atmosphere can be reliably communicated regardless of the orientation of the sealing body 40. It is preferable to provide a plurality of through-holes 41 because the area of the vacuum opening can be increased.

  If the plurality of through holes 41 are orthogonal to each other as shown in FIG. 3B and pass through the central portion of the sealing body 40, for example, the shape of the through-hole 20 is changed from the planned shape. It can be said that the through-hole 41 of the sealing body 40 is considerably close to the through-hole 20 and thus the opening area can be reduced by the other through-holes 41 even if the opening area is reduced. As the sealing body 40, for example, a gold tin alloy (AuSn), a gold germanium alloy (AuGe), a gold silicon alloy (AuSi), or the like is used. As for these mass ratios, for AuSn, the weight of Sn is, for example, in the range of 20 ± 0.5%, and for AuGe, the weight of Ge is, for example, in the range of 12.5 ± 0.5%. For AuSi, the weight of Si is, for example, in the range of 3.15 ± 0.5% of the whole.

  Next, the vacuum heating apparatus 50 will be described with reference to FIG. The vacuum heating device 50 is for sealing the crystal unit 10 in a container by making the storage space 16 into a vacuum atmosphere and heating and melting the sealing body 40. In FIG. 4, reference numeral 51 denotes a base, and an elevating mechanism 52 is provided below the base 51 so that the base 51 can be raised and lowered. Further, a mounting stage 54 is provided on the base 51 via a heat insulating material 53, and a plurality of case bodies 11 can be arranged and mounted thereon. A glass chamber 55 is provided so as to surround the mounting stage 54, and an internal space 56 defined by the inner wall of the chamber 55 and the base 51 is hermetically sealed. An exhaust pipe 57 is connected to the side wall of the chamber 51, and the exhaust pipe 57 can suck air in the internal space 56. A heater 58 is provided above the chamber 55 to heat the internal space 56. Further, a heat insulating case 59 is provided surrounding the chamber 55 and the heater 58 so that the heat of the heater 58 does not escape to the outside.

  Next, an electronic component manufacturing method will be described. As shown in FIG. 5, first, a case body 11 is prepared, and through holes 20 are formed in the bottom surface 13 of the case body 11 by etching. Next, a metal layer 21 is formed in the through hole 20. The metal layer 21 is formed by forming a metal film using, for example, a sputtering apparatus, patterning by photolithography, and removing unnecessary portions by wet etching. Subsequently, as shown in FIGS. 6A and 6B, the conductive adhesive 33 is applied to the electrodes 14a and 14b, and the lead-out electrodes 32a and 32b of the crystal unit 10 are disposed on the conductive adhesive 33 so as to be conductive. The crystal unit 10 is fixed to the case body 11 by curing the adhesive 33. Next, as shown in FIG. 7, for example, a brazing material is applied to the upper surface of the side wall of the case body 11, and the brazing material is melted and fixed to bond the lid body 12 to the case body 11. As a result, the crystal unit 10 is stored in the storage space 16.

  Subsequently, the case body 11 is inverted so that the side on which the through hole 20 is formed faces upward, and the sealing body 40 is positioned so as to cover the through hole 20. That is, the sealing body 40 is dropped into the through hole 20. The process of handling the sealing body 40 is performed using vacuum suction or a transfer ball mounting machine. Conventionally, since handling was performed in a vacuum, it took time to form a vacuum state, and when a problem occurred, it was necessary to return to the atmospheric state, which was troublesome. However, since the handling of the sealing body 40 is performed in the atmosphere, the operation is easy and correction can be easily performed when the positions of the sealing body 40 and the through hole 20 are shifted. Next, for example, the case body 11 is placed on the placement stage 54 of the vacuum heating device 50 by a conveying means (not shown), and the elevating mechanism 52 raises the base 51, so that the base 51 and the chamber 55 are brought together. Connected, the internal space 56 is hermetically sealed. Thereafter, the atmosphere of the internal space 56 is evacuated through the exhaust pipe 57, and as a result, the air in the storage space 16 of the crystal unit 10 is transferred to the sealing body 40 as shown in FIG. The air is sucked outside through the through hole 41 and the gap 42 between the sealing body 40 and the through hole 20, and the atmosphere of the storage space 16 is depressurized (becomes a vacuum).

  Next, when the case body 11 is heated to the melting point of the sealing body 40 or a temperature slightly higher than the melting point of the sealing body 40 by the heater 58 in a state where the atmosphere of the storage space 16 is kept in vacuum, as shown in FIG. The sealing body 40 and the metal layer 21 are dissolved, and the through hole 20 is closed by the dissolved metal. Thereafter, the heating of the heater 58 is stopped and the internal space 56 is cooled to obtain an airtight electronic component in which the arrangement atmosphere of the crystal unit 10 is evacuated as shown in FIG.

  According to the above-described embodiment, when the vacuum hole is formed through the through-hole 20 formed in the case body 11 that accommodates the crystal resonator 10 and the through-hole 20 is sealed with the sealing body 40, the sealing body 40 is used. Since the through hole 41 is open, the storage space 16 can be quickly evacuated through the through hole 41 while the sealing body 40 is positioned in the through hole 20. Therefore, since the handling of the sealing body 40 can be performed outside the vacuum container, for example, before evacuation, the handling of the sealing body 40 is facilitated.

  Further, as another embodiment, a configuration described below may be adopted. The description will focus on the differences from the above-described embodiment. As shown in FIG. 9, the crystal resonator 10 according to this embodiment is manufactured by using three wafers: a device wafer 61, a lid wafer 62 forming a lid, and a base wafer 63. . In the element wafer 61 and the base body wafer 63, a crystal resonator 10 forming area 64 and a base body forming area 65 are indicated by dotted lines, respectively. As shown in FIG. 10A, excitation electrodes 31 a and 31 b and extraction electrodes 32 a and 32 b are formed on the element wafer 61, and a frame portion 66 surrounding the crystal resonator 10 is formed. The frame portion 66 serves as a portion for joining the lid body 12 and the base body 67. In the base body wafer 63, a recess 68 is formed by etching or the like, and electrodes 14a and 14b are formed.

  Next, solder is vapor-deposited on the surface of the base body wafer 63, the element wafer 61 is bonded to the surface of the base body wafer 63, and the solder is heated and dissolved, whereby the base wafer 63. A device wafer 61 is bonded to the device. That is, the frame 66 of the crystal unit 10 and the upper surface of the side wall of the recess 68 of the base body 67 are joined. Subsequently, solder is vapor-deposited on the surface of the element wafer 61, the lid wafer 62 is bonded to the surface of the element wafer 61, and the solder is heated and dissolved, whereby the element wafer 61 is covered. A wafer 62 is bonded together. Thereafter, the crystal resonator 10 is packaged by cutting the crystal resonators 10 one by one using a dicing saw.

  Since the above process is performed in the atmosphere because the alignment between the wafers becomes difficult when performed in a vacuum, the storage space 16 of the crystal unit 10 does not become a vacuum atmosphere. Therefore, as shown in FIG. 10B, by forming the through hole 20 and the metal layer 21 at the bottom of the base body 67 and arranging the sealing body 40 in the through hole 20 to perform sealing, As in the previous embodiment, it is possible to create a state in which the crystal unit 10 is placed in a vacuum atmosphere.

  Further, as another embodiment, an example using a spherical sealing body 40 that does not have the through hole 41 can be given. As shown in FIG. 11 (a), the case body 11 is formed with a square-shaped, for example, hexagonal through-hole 20, and the diameter of the through-hole 20 is constant in the depth direction. The diameter is not reduced as in the example. A metal layer 21 is formed on the surface of the through hole 20. As shown in FIG. 11 (b), when the spherical sealing body 40 is positioned so as to close the through-hole 20, the sealing body 40 and the through-hole 20 are in a sphere-hexagonal relationship. As shown in FIG. 11 (c), a gap 42 is formed between them. Then, the crystal unit 10 can be hermetically sealed by vacuuming through the gap 42.

  In addition, as shown in FIG. 12, in the configuration in which the hexagonal through hole 20 is formed so that the hole diameter becomes narrower from the outside to the inside of the case body 11, the spherical sealing body 40 and the through hole 20 are formed. A gap 42 is formed between the two. Moreover, it is preferable that the shape of the sealing body 40 and the through hole 20 is set so that a gap 42 of 30 μm or more is formed between the sealing body 40 and the through hole 20. When the shape of the through hole 20 is narrowed as described above, the sealing body 40 and the through hole are formed so that one of the cross section of the sealing body 40 and the cross section of the through hole 20 is circular and the other is square. 20 may be configured. Therefore, for example, as shown in FIG. 13, a cube having a quadrangular cross section is used for the sealing body 40, and the through hole 20 has a round shape so that the cross section is circular. Also in this case, when the sealing body 40 is positioned in the through-hole 20, a gap 42 is formed between them, so that the container can be hermetically sealed in a state where the container is in a vacuum atmosphere. . In the present invention, the auxiliary sealing layer (the metal layer 21 in the above-described example) is not necessarily required. Depending on the combination of the material of the container and the sealing body 40, there is no auxiliary sealing layer. In addition, the sealed body that has been dissolved after sealing sufficiently adheres to the container.

It is the longitudinal cross-sectional view and transverse cross-sectional view of the crystal resonator which concern on embodiment of this invention. It is an enlarged view of the through-hole formed in the container which accommodates the said crystal oscillator. It is explanatory drawing which showed typically the sealing body arrange | positioned at the said through-hole. It is a longitudinal cross-sectional view of the vacuum heating apparatus which evacuates and heats the said quartz oscillator. It is explanatory drawing which showed a mode that a through-hole was provided in the said container. It is explanatory drawing which showed a mode that the said crystal oscillator was accommodated. It is explanatory drawing which showed the mode when the said crystal oscillator was accommodated. It is explanatory drawing which showed typically a mode that the said crystal oscillator was sealed. It is a figure explaining the accommodation method of the crystal oscillator in other embodiments of the present invention. It is a longitudinal cross-sectional view of the crystal oscillator in other embodiment of this invention. It is explanatory drawing explaining the through-hole and sealing body in other embodiment of this invention. It is explanatory drawing explaining the through-hole and sealing body in other embodiment of this invention. It is explanatory drawing explaining the through-hole and sealing body in other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Crystal oscillator 11 Case body 12 Cover body 16 Storage space 20 Through-hole 21 Metal layer 40 Sealing body 41 Through-hole 42 Gap 50 Vacuum heating apparatus

Claims (8)

In a method of manufacturing an electronic component in which an electronic component main body is provided in a vacuum-tight airtight container,
A step of positioning a sealing body in which a through-hole for vacuuming is formed in a through-hole formed in a container in which an electronic component main body is stored;
Next, a process of evacuating the inside of the container by setting the atmosphere in which the container is placed to a vacuum atmosphere,
Then, the process of melt | dissolving a sealing body and sealing the said through-hole is included, The manufacturing method of the electronic component characterized by the above-mentioned.   The method for manufacturing an electronic component according to claim 1, wherein a plurality of through holes are formed in the sealing body.   The method for manufacturing an electronic component according to claim 2, wherein the plurality of through holes are orthogonal to each other. In a method of manufacturing an electronic component in which an electronic component main body is provided in a vacuum-tight airtight container,
A step of positioning a spherical sealing body in a square-shaped through hole formed in a container in which an electronic component main body is stored;
Next, a process of evacuating the inside of the container by setting the atmosphere in which the container is placed to a vacuum atmosphere,
Then, the process of melt | dissolving a sealing body and sealing the said through-hole is included, The manufacturing method of the electronic component characterized by the above-mentioned.   5. The method of manufacturing an electronic component according to claim 1, wherein the through hole has a smaller hole on the back side than the outside.   5. The electronic component according to claim 4, wherein when the sealing body is positioned in the through hole, both shapes are set so that a gap of 30 μm or more is formed therebetween. Manufacturing method. In a method of manufacturing an electronic component in which an electronic component main body is provided in a vacuum-tight airtight container,
The step of positioning the sealing body in the through hole of the container in which the electronic component main body is housed and the through hole in which the hole becomes smaller toward the back side from the outer surface is formed;
Next, a process of evacuating the inside of the container by setting the atmosphere in which the container is placed to a vacuum atmosphere,
Then, the step of dissolving the sealing body and sealing the through hole,
One of the cross section of the said sealing body and the cross section of a through-hole is circular, and the other is a square, The manufacturing method of the electronic component characterized by the above-mentioned.   The method for manufacturing an electronic component according to claim 1, wherein a sealing auxiliary layer that is compatible with the sealing body is formed in the through hole of the container.

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