JP2013051510A - Piezoelectric vibration device encapsulation member manufacturing method and piezoelectric vibration device using encapsulation member manufactured by this method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric vibration device encapsulation member manufacturing method which makes it possible to reduce the diameters of through holes and also prevents chipping, etc. at hole boring time, and a piezoelectric vibration device using an encapsulation member manufactured by this method.SOLUTION: The present invention relates to a manufacturing method for a piezoelectric vibration device encapsulation member which hermetically seals the excitation electrode of the piezoelectric vibration device. The manufacturing method includes a through hole formation step of forming a through hole used to electrically connect between two main planes of a base material of the encapsulation member and a conductive member formation step of forming a conductive member in the through hole. The through hole formation step comprises: a first step of forming in the main plane a hole 60 having a tapered inner side face 61 whose opening diameter inside the base material is smaller than its opening diameter at one main plane 200 of the base material; and a second step of forming a through hole by boring from a position on the inner side face 61 which is apart from the vicinity of the main plane.

Description

  The present invention relates to a method for manufacturing a sealing member of a piezoelectric vibration device and a piezoelectric vibration device using a sealing member obtained by the manufacturing method.

  Piezoelectric vibration devices are widely used in various communication devices such as mobile phones. For example, taking a crystal resonator as an example of a piezoelectric vibration device, the main components of a general crystal resonator are a substantially rectangular parallelepiped crystal resonator element in which excitation electrodes are formed opposite to the front and back main surfaces, and a crystal resonator element. A ceramic container body having a recess for accommodating and a metal lid body hermetically sealing the excitation electrode by joining the container body. Here, the excitation electrode is led to a connection electrode formed at one end of the crystal resonator element via an extraction electrode. A mounting electrode that is bonded to the connection electrode via a bonding material is formed on the bottom surface of the concave portion of the container body. The mounting electrode is electrically connected to an external connection terminal formed on the bottom surface of the container body through a through electrode (so-called via) filled with a conductor in a through hole penetrating the base material of the container body in the thickness direction. It is connected. A piezoelectric vibration device having a configuration using such a through electrode is disclosed in Patent Document 1, for example.

  As the above-mentioned various communication devices are becoming thinner and more advanced, miniaturization and higher density of various electronic components mounted on the internal board of the device demands ultra-small and thin products for piezoelectric vibration devices. It has been. Taking the above-described quartz resonator as an example, when the rectangular shape of the rectangular parallelepiped crystal resonator becomes ultra-small with a size of 2.0 mm × 1.6 mm or less, the aforementioned penetrating electrode is in contact with the container body. The ratio of the occupied area (diameter at both ends of the through electrode) is relatively large. Since various electrode patterns and the like are arranged at high density around the end portion of the through electrode, it is necessary to further reduce the diameter of the through electrode.

Japanese Patent No. 3523502 JP 2010-206322 A

  As described above, ceramic is generally used as the material of the container body of the conventional piezoelectric vibration device. However, when the piezoelectric vibration device becomes ultra-small, ceramic is limited in terms of firing accuracy and the like. Since it is coming, it is possible to cope with the miniaturization by using a crystalline material such as crystal or glass as the material of the container. In the case of a container body made of a crystalline material such as crystal or glass, a beam or blast (sand blast or the like) can be used as a method of drilling the through hole of the through electrode in addition to a wet etching method.

  However, in the case of drilling by a wet etching method, an anisotropic material such as quartz generates an asymmetric shape due to crystal orientation, and it is difficult to appropriately manage etching time due to a difference in etching rate (corrosion rate). . Thereby, it will become a shape from which the opening diameter differed greatly by the both ends (front and back main surface of a to-be-processed object) of a through-hole. On the other hand, in the case of an isotropic material such as glass, the opening diameter is increased in proportion to the depth of the through hole, so that a through hole having a large opening diameter is formed. This is due to the so-called undercut, in which corrosion proceeds directly under the etching mask. That is, in any material, it is difficult to form a through hole having a desired shape with high accuracy by chemical means.

  On the other hand, when a beam (laser beam or the like) or blast (sand blast or the like) is used for drilling, compared to chemical means such as wet etching, the difference in the opening diameters at both ends of the through hole is small. There are advantages that can be formed. However, these processing means have the following problems. When using a beam, it is possible to form fine through holes, but since the beam is irradiated perpendicularly to the workpiece, chipping and chipping caused cracks (hereinafter abbreviated as chipping etc.) May occur. In addition, although blasting (for example, sandblasting) can form through holes having substantially the same diameter, there is a problem that it is not practical in terms of processing speed. In other words, if a rough abrasive is used to shorten the processing time, chipping or the like is likely to occur, and if a fine abrasive is used to suppress chipping or the like, the processing time becomes long and production efficiency is reduced. Exists.

  The present invention has been made in view of the above points, and is obtained by a method for manufacturing a sealing member of a piezoelectric vibration device that can reduce the diameter of a through-hole and prevent chipping during drilling, and the manufacturing method. An object of the present invention is to provide a piezoelectric vibration device using the sealing member formed.

  In order to achieve the above object, the invention of claim 1 is a method for manufacturing a sealing member of a piezoelectric vibration device in which the excitation electrode of the piezoelectric vibration element is hermetically sealed. A through-hole forming step for forming a through-hole for electrically connecting the surfaces, and a conductive member forming step for forming a conductive member in the through-hole. A first step of forming holes on both main surfaces, each having an opening diameter smaller than the opening diameters on both main surfaces of the material and having tapered inner side surfaces, and among the inner side surfaces, This is a method for manufacturing a sealing member for a piezoelectric vibration device, comprising: a second step of forming a through hole by drilling from a position separated from the vicinity of both main surfaces.

  According to the said manufacturing method, generation | occurrence | production of the chipping etc. at the time of drilling a through-hole can be suppressed. This is because, in the first step, the opening diameter in the base material is smaller than the opening diameter in the both main surfaces of the base material, and holes having tapered inner side surfaces are formed in both the main surfaces, respectively. In the two steps, by punching from the position apart from the vicinity of both main surfaces of the inner surface. That is, in the case of drilling by irradiating or spraying a beam or abrasive (used for blasting) perpendicularly to the sealing member having a flat surface, chipping or the like may occur at the end of the through hole. On the other hand, in the manufacturing method of the sealing member of the present invention, since processing is started from the middle of the inner side surface, it is possible to prevent the occurrence of chipping or the like in the regions near the two main surfaces that do not contribute to processing. it can. Furthermore, since processing is started from the middle of the inner side surface, the influence of perforation on the main surface of the sealing member can be reduced. As a result, the main surface of the sealing member around the end portion of the through hole can be maintained in a good state. Thus, various conductors such as external connection terminals can be reliably formed. The perforation in the second step may be performed not only from one main surface side of the sealing member but also from the other main surface side of the sealing member.

  In order to achieve the above object, the holes in the first step may be formed by a wet etching method. For example, by using a crystalline material (such as crystal or glass) for the base material of the sealing member, the tapered inner surface of the hole in the first step can be easily formed. In this case, the inclination angle of the inner surface with respect to the main surface of the base material is 20 to 70 degrees in the case of quartz (depending on the axial direction), and about 45 degrees in the case of glass.

  When a crystalline material is used for the base material of the sealing member and a through hole is formed in the sealing member by a wet etching method, the opening diameter of the through hole increases in proportion to the depth of the through hole. Although a large through hole is formed, when the hole formed in the first step of the present invention is a bottomed hole, wet etching is not performed until the sealing member is penetrated. The expansion of the diameter can be suppressed, which is effective for reducing the diameter of the through hole. In the present invention, the hole formed in the first step is not limited to the bottomed hole, and the opening diameter in the base material is smaller than the opening diameters in both main surfaces of the base material, and the tapered inner surface is formed. May be a through-hole. In addition, by dissolving the base material from both main surfaces of the sealing member to a depth in the middle of the sealing member by a wet etching method, the remaining thickness of the sealing member to be perforated in the second step is reduced. The time required for drilling can be shortened.

  Moreover, by forming the hole in the first step by a wet etching method, the inner wall surface of the hole after etching can be made smoother than the inner wall surface of the hole formed by mechanical processing. And in a 2nd process, since a process is started from the middle of the inner surface of the hole formed at the 1st process, the area | region of both the main surfaces of the sealing member which does not contribute to a process can be made into a smooth surface. Thus, since the area | region of both the said main surfaces is a smooth surface, the expansion of the chipping generation | occurrence | production area | region to the surface (main surface) of a to-be-processed object (sealing member) can be prevented. Further, since the surface of the inner side surface is formed in a smooth state by wet etching, it is effective for suppressing chipping during drilling in the second step.

  In order to achieve the above object, the perforation may be performed by a beam or blast in the second step. By drilling using these punching means, it is possible to punch the base material portion remaining in the formation of the hole in the first step with substantially the same diameter. As the beam, an energy beam such as a laser beam or an electron beam can be used. Further, as the blasting, mechanical blasting (shot blasting or the like), pneumatic blasting (air blasting such as sand blasting), or wet blasting can be applied. In the case of blasting, since the inner surface of the hole formed in the first step is tapered, a rectifying effect of the polishing agent due to the contact of the polishing agent obliquely can be expected. In other words, in the case of a rectangular hole in cross-section, the abrasive stays in the corner of the bottom of the hole and the flow of the abrasive tends to be non-uniform, but if the inner surface is a tapered hole, the stay region is difficult to form. Therefore, it becomes easy to promote replacement of the abrasive. This improves the processing efficiency.

  When the perforation is performed by blasting, blasting may be performed after masking with a resist film or the like so as to cover a predetermined pattern on both main surfaces of the base material and regions near both main surfaces of the holes. In this case, since the regions in the vicinity of both main surfaces that do not contribute to blasting are protected from the abrasive by the resist film or the like, processing can be performed without reducing the projection diameter of the abrasive, which is suitable for batch processing.

  A piezoelectric vibration element in which an excitation electrode is formed is mounted on a sealing member obtained by the method for manufacturing a sealing member for a piezoelectric vibration device according to any one of claims 1 to 3, and the excitation electrode If the piezoelectric vibration device is hermetically sealed with another sealing member, it is possible to suppress the occurrence of chipping or the like when the through hole is drilled in the sealing member. Moreover, the influence of perforation on the main surface of the sealing member can be reduced. As a result, the main surface of the sealing member around the end portion of the through hole can be maintained in a good state. Thus, various conductors such as external connection terminals can be reliably formed.

  As described above, according to the present invention, a method for manufacturing a sealing member of a piezoelectric vibration device that can reduce the diameter of a through-hole and prevent chipping during drilling and the sealing obtained by the manufacturing method A piezoelectric vibration device using the member can be provided.

1 is a schematic cross-sectional view of a crystal resonator showing an embodiment of the present invention. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The A section enlarged view in FIG. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The B section enlarged view in FIG. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The cross-sectional schematic diagram which shows the manufacturing method of the sealing member of this invention. The expanded sectional view of the penetration electrode which shows other embodiments of the present invention. The expanded sectional view of the penetration electrode which shows other embodiments of the present invention.

  Hereinafter, an example in which the present invention is applied to a crystal resonator as a piezoelectric vibration device will be described. First, after describing the crystal resonator in the present invention, a method for manufacturing a sealing member constituting the crystal resonator will be described.

  The crystal resonator in the present invention is a substantially rectangular parallelepiped shape, and is a surface-mount type crystal resonator in which an external connection terminal 24 connected to an external substrate is provided on the bottom surface of the housing. The crystal unit 1 includes a sealing member 2 (container) made of crystal having a recess 20 for accommodating a crystal resonator, and an AT-cut crystal resonator that is bonded to the recess 20 via a bonding member 8. 3 and a flat lid 4 made of borosilicate glass that hermetically seals the recess 20 is a main constituent member. In the embodiment of the present invention, crystal is used for the sealing member 2, but is not limited to crystal, and a crystalline material such as borosilicate glass may be used in addition to the crystal.

  In FIG. 1, the sealing member 2 is made of quartz called a Z plate. The sealing member 2 is formed with a bank portion 22 having a substantially rectangular shape in plan view, and a metal brazing material (not shown) is formed on the top surface of the bank portion 22 in a circumferential shape. A region inside the bank portion 22 is a recess 20. A step portion 23 is formed in a region near the short side of the inner bottom surface 21 of the recess 20. A pair of mounting electrodes 7, 7 that are cantilever-bonded via the crystal resonator element 3 and the bonding member 8 are formed in parallel on the upper surface of the stepped portion 23. The mounting electrode 7 is electrically connected to an external connection terminal 24 formed on the bottom surface of the sealing member 2 via an internal wiring (not shown) formed on the inner bottom surface 21 of the through electrode 6 and the recess 20. ing. In addition, by supporting the crystal resonator element above the step portion 23 via the bonding member 8, the free end of the crystal resonator element can be compared with the case where the crystal resonator element is directly disposed on the upper portion of the inner bottom surface 21. A larger distance from the inner bottom surface 21 can be secured. Thereby, even when the crystal unit 1 receives an external impact or the like and the free end side is bent, the contact between the free end and the inner bottom surface 21 side can be prevented. In addition, application of this invention is not limited to the sealing member of the structure which has the said step part, It is applicable also to the sealing member of a structure which does not have a step part.

  In the present embodiment, the through electrode 6 is patterned using a photolithographic technique, and a through hole is drilled by a combination of wet etching and laser processing, and then a metal film serving as a seed layer is sputtered to form the inner wall surface of the through hole. The conductive member is deposited on the metal film by electrolytic plating to fill the inside of the through hole (details of the method of forming the through electrode will be described later).

  The crystal resonator element 3 is an AT-cut crystal resonator plate having a rectangular shape in plan view and cut at a predetermined angle. A pair of excitation electrodes (not shown) are formed on the front and back main surfaces of the crystal resonator element 3 so as to face each other, and are led out from the respective excitation electrodes to one short side end portion of the crystal resonator element by an extraction electrode. Terminations led out to one short side end of the crystal resonator element are connection electrodes (not shown), which are joined to the mounting electrode 7 via the joining member 8. In the present embodiment, a stud bump made of gold is used as the bonding member 8. However, the present invention is not limited to this, and a stud bump made of a metal other than gold, a metal plating bump, or a conductive adhesive is used. May be used.

  In FIG. 1, the lid 4 is a flat plate made of glass. On one main surface side of the lid 4, a metal film is formed in a circumferential shape at a position corresponding to the metal brazing material on the upper surface of the bank portion 22 of the sealing member 2 (not shown). After the lid body 4 has undergone a predetermined process such as frequency adjustment of the crystal resonator element 3 bonded on the mounting electrode 7, the metal film on the one main surface side of the lid body 4 is the metal on the upper surface of the bank portion 22. After the lid 4 is positioned and placed on the sealing member 2 so as to come into contact with the brazing material, these metals (the metal film of the lid and the metal brazing material of the sealing member) are fused and integrated in a heated atmosphere. By doing so, the sealing member 2 is joined in an airtight manner. The molten and integrated state is the metal brazing material 5 in FIG. The above is the description of the crystal resonator in the present invention.

Next, the main steps in the method for manufacturing the sealing member constituting the above-described crystal resonator will be described.
(Recess formation process)
First, as shown in FIG. 2, a quartz wafer W having a predetermined size is prepared. In the description of the present embodiment, the manufacturing method is shown for a single sealing member in the drawings, but in actuality, a large number of sealing members are manufactured in a lump in a state of being arranged in a lattice shape. The crystal wafer W has front and back main surfaces (one main surface 200 and another main surface 201) which are smooth surfaces, and a metal film (gold in this embodiment) is formed on these front and back main surfaces by sputtering ( (Not shown). Then, a resist film (positive type) is applied on the metal film formed by sputtering, and exposure and development are performed in a predetermined pattern. FIG. 3 shows a state in which the recess 20 is formed by wet etching with the formation region of the recess 20 opened by the above method, and the resist film and the metal film are removed. Thereafter, in order to further form the stepped portion 23, after forming a metal film by sputtering, a resist film is applied on the metal film, and exposure and development are performed in a predetermined pattern. And the step part 23 is formed in the recessed part 20 as shown in FIG. 4 by wet etching. FIG. 4 shows a state where the resist film and the metal film are removed.

(Through hole forming process)
Hereinafter, the through-hole forming process for forming the through-hole for electrically connecting the two main surfaces of the base material of the sealing member will be described separately for the first process and the second process.
-First step-
After re-forming the above-described metal film on the front and back main surfaces of the wafer W by sputtering, the resist film in the region where the bottomed hole is to be formed is removed by exposure / development processing using a photolithography technique (see FIG. 6). 5 to 10, the display of the metal film formed by the above-described sputtering is omitted.

  Then, wet etching is performed in a state where a region for forming a bottomed hole is opened as indicated by an arrow in FIG. As shown in FIG. 7, a hole 60 is formed by the wet etching. Here, as shown in FIG. 8, the hole 60 has a smaller opening diameter inside the base material than the opening diameters on both main surfaces of the base material (W), and is continuous with the tapered inner side surface 61 and the inner side surface 61. The shape has a hole bottom surface 62. The hole 60 is formed to face both main surfaces of the sealing member (the upper surface of the step portion 23 and the other main surface 201). Since the inner surface 61 is made of quartz, which is an anisotropic crystal material, as the base material of the sealing member 2, during the wet etching, chemical dissolution proceeds at an angle specific to the crystal orientation of the quartz, and the hole 60 having the shape described above is formed. This is preferable because it can be easily molded. Glass may be used as the base material of the sealing member 2 other than quartz. The hole 60 may be formed by dry etching using a photolithography technique, in addition to wet etching using a photolithography technique. Further, the cross-sectional shape of the inner surface is not limited to a linearly inclined shape, and may be in a state of being inclined in an arc shape.

  If it is the manufacturing method of the sealing member of this invention, a taper-shaped inner surface is easy by using a crystalline material for the base material of a sealing member, and using a wet etching method for formation of the hole in the said 1st process. Can be molded. In addition, when the hole 60 formed in the said 1st process of this invention is a bottomed hole, since wet etching is not performed until it penetrates a sealing member, expansion of the opening diameter in the main surface of a sealing member is suppressed. This is effective in reducing the diameter of the through hole. In addition, by dissolving the base material from both main surfaces of the sealing member to a depth in the middle of the sealing member by a wet etching method, the remaining thickness of the sealing member to be perforated in the second step is reduced. The time required for drilling can be shortened.

  Further, by forming the hole 60 in the first step by a wet etching method, the inner wall surface of the hole 60 after etching can be made smoother than the inner wall surface of the hole formed by mechanical processing. In the second step, since the processing is started from the middle of the inner side surface 61 of the hole 60 formed in the first step, regions near both main surfaces of the sealing member that do not contribute to the processing can be made smooth. . Thus, since the area | region of both the said main surfaces is a smooth surface, the expansion of the chipping generation | occurrence | production area | region to the surface (main surface) of a to-be-processed object (sealing member) can be prevented. Moreover, since the surface of the inner surface 61 is formed in a smooth state by wet etching, it is also effective in suppressing chipping during drilling in the second step.

-Second step-
Next, of the holes 60, 60 formed on the front and back main surfaces of the wafer W in the first step described above, the laser beam L (main) from above the recess 20 with respect to the hole 60 on one main surface side (recess 20 side). In the embodiment, a CO2 laser is used (wavelength 10600 nm) is irradiated (see FIG. 9). Thereby, the base material part below the bottomed hole remaining by the wet etching in the first step is processed, and a through hole H penetrating to the hole 60 on the other main surface 201 side is drilled (see FIG. 11). In addition, the area | region drilled by a 2nd process becomes a substantially straight tube shape in sectional view (code | symbol 63 in FIG. 11). Details of the formation of the through hole H will be described with reference to FIG. FIG. 10 is an enlarged view of portion B in FIG. As shown in FIG. 10, the laser beam L is irradiated to a position separated from the vicinity of one main surface 200 (the upper surface of the step portion 23) in the inner surface 61 of the hole 60. When the laser beam diameter is D1 and the opening diameter of one main surface of the hole 60 is D2, the relationship is D1 <D2. By forming the hole 60 having an opening diameter larger than the laser beam diameter, the region of the inner side surface 61 (the region in the vicinity of the one main surface 200) indicated by S in the drawing becomes a region that does not contribute to drilling. That is, by starting the processing from the middle of the inner side surface 61 of the hole 60, the regions in the vicinity of both main surfaces of the sealing member that do not contribute to the processing can be made smooth. Thus, since the area | region of both the said main surfaces is a smooth surface, the expansion of the chipping generation | occurrence | production area | region to the surface (main surface) of a to-be-processed object (sealing member) can be prevented.

  In the present embodiment, the hole 60 has an opening diameter D2 (0.10 to 0.15 mm in the present embodiment) that is larger than the laser beam diameter D1. In addition, S shown in FIG. 10 is about 0.005 to 0.01 mm, and this represents a state in which the laser beam L is irradiated to the opening portion of the hole 60 so as to be positioned substantially at the center. Although the hole 60 formed in the first step has an opening diameter (D2) larger than the laser beam diameter, the dimension of the opening diameter of the hole 60 is not limited to the above dimension. Moreover, the dimension of D1 is not limited to the said dimension, D1 should just be set smaller than D2. In addition, when using a laser, the kind of laser is not limited to the laser of this embodiment, You may use the laser of another kind (wavelength). For example, a YAG laser, a YVO4 laser, a green laser, or the like can be used.

  According to the manufacturing method of the sealing member of the present invention, it is possible to suppress the occurrence of chipping or the like when the through hole H is drilled. This is because, in the first step, the opening diameters in the base material are smaller than the opening diameters in the two main surfaces of the base material of the sealing member, and the holes 60 having the tapered inner side surfaces 61 are formed in the two main surfaces, respectively. In the second step, the inner surface 61 is formed and drilled from a position away from the vicinity of both main surfaces. When drilling by irradiating or spraying a beam or an abrasive (used for blasting) perpendicularly to a sealing member having a flat surface, chipping or the like may occur at the end of the through hole. On the other hand, in the manufacturing method of the sealing member of the present invention, since processing is started from the middle of the inner side surface 61, it is possible to prevent the occurrence of chipping or the like in the regions near the two main surfaces that do not contribute to processing. it can. Furthermore, since the machining is started from the middle of the inner surface 61, the influence of perforation on the main surface of the sealing member can be reduced. As a result, the main surface of the sealing member around the end of the through hole can be maintained in a good state, so that various conductors such as the mounting electrode 7, the internal wiring, and the external connection terminal 24 can be reliably formed.

  In the second step, the perforation may be performed by blasting. Specifically, mechanical blasting such as shot blasting, pneumatic blasting such as sand blasting, or wet blasting in which an abrasive solution is sprayed from a nozzle at a high pressure can be applied. By performing the perforation by blasting, fine processing can be performed with high accuracy. This is because in the case of blasting, the pattern is formed by exposure using various resist films, so that the opening can be positioned with high accuracy. Further, since blast processing is performed using a resist film patterned by exposure as a protective film, it is superior to the beam in terms of projection (irradiation) position control compared to processing using a beam that does not form such a protective film. In this case, blasting may be performed after forming a resist film with an electrodeposition resist so as to cover a predetermined pattern on both main surfaces of the substrate and a region in the vicinity of both main surfaces of the hole. In this case, the regions in the vicinity of the two main surfaces that do not contribute to the blasting process are protected from the abrasive by the resist film. Excellent. It should be noted that wet blasting that can prevent abrasives from scattering is suitable for a piezoelectric vibration device that is ultra-compact and that is subjected to various highly accurate processes in a minute region.

(Conductive member forming process)
A conductive member (metal film) is formed on the inner wall surface of the through hole H shown in FIG. 11 by sputtering, and at the same time, a metal film is also formed in other regions (such as the inner bottom surface of the recess 20). These metal films are exposed and developed by a photolithography technique to form internal wiring in a predetermined shape (not shown). In this embodiment, the conductive member (seed layer) formed on the inner wall surface of the through hole H is a multilayer film in which a sputtering film of Cu is laminated on a sputtering film of Ti or Mo. For the internal wiring, a multilayer film in which a Cu plating layer is laminated thereon is used. Then, a through electrode 6 is formed by depositing a conductive member M (Cu in this embodiment) on the seed layer of the through hole H by an electrolytic plating method (see FIG. 12. In FIG. 12, the description of the internal wiring is shown). (Omitted). After the through electrode 6 is formed, a pair of mounting electrodes 7 and 7 (Cu in this embodiment) is formed at one end of the through electrode 6 on the upper surface side of the step portion 23 as shown in FIG. In the embodiment of the present invention, the metal used for the conductive member M, the internal wiring, and the mounting electrode is not limited to the type and the film configuration. Types or film configurations other than the above types and film configurations may be used.

(External terminal formation process)
After the conductive member forming step, the external connection terminal 24 is formed through a predetermined step (see FIG. 13). The external connection terminal 24 is formed so as to cover one end portion on the other main surface 201 side of the sealing member of the through electrode 6, whereby the mounting electrode 7 passes through the through electrode 6 (or internal wiring (not shown)). It is electrically connected to the external connection terminal 24.

Note that the inside of the through hole H does not necessarily need to be filled with a conductive member. For example, as shown in FIG. 14, the conductive member (metal film M) is attached to the inner wall surface of the through hole. The structure which sealed the through-hole by ensuring conduction | electrical_connection of the front and back main surfaces, and filling the resin material P in the space | gap part may be sufficient. Alternatively, as shown in FIG. 15, the conductive member (metal film M) is attached to the inner wall surface of the through hole, and the conductive member (metal film M) is also applied to one end region of the through hole on the recess 20 side. A structure in which the resin material P is partially filled and the remaining region of the through hole is partially filled may be used. In the embodiment of the present invention, the through electrode 6 is formed at a position where the external connection terminal 24 overlaps the external connection terminal 24 in a plan view. However, the application of the present invention is not limited to this configuration. A position where they do not overlap, for example, an external connection terminal may be disposed on the periphery of the bottom surface of the crystal resonator, and the through electrode may be formed so that the through electrode 6 is positioned in the inner region. In this case, a photosensitive resin material such as PBO (polybenzoxazole) is used for the resin material P. The resin material P is not limited to PBO, and a resin material having good adhesion to the material constituting the sealing member can be used.
The above is the description regarding the main process of the manufacturing method of the sealing member which comprises the crystal oscillator in this invention.

  In the embodiment of the present invention, the hole 60 is formed in each of the main surfaces (specifically, the step portion 23 and the other main surface 201) of the sealing member 2 in the first step. It is not necessary to form low holes on both main surfaces of the member, and low holes may be formed only on one main surface side. In this case, it is preferable to form a low hole on the concave portion 20 side on which the crystal resonator element is mounted and which is the internal space of the crystal resonator. Further, the hole formed in the first step in the present invention is not limited to the bottomed hole, and the opening diameter inside the base material is smaller than the opening diameters on both main surfaces of the base material, and the tapered inner side surface May be a through-hole.

  In the embodiment of the present invention, a method for manufacturing a sealing member for a surface-mounted crystal resonator is taken as an example, but in addition to the crystal resonator, other piezoelectric vibrations used for electronic devices such as a crystal filter and a crystal oscillator It is applicable also to the manufacturing method of the sealing member of a device.

  The present invention can be implemented in various other forms without departing from the spirit or main features thereof. Therefore, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. The scope of the present invention is indicated by the claims, and is not restricted by the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  It can be applied to mass production of piezoelectric vibration devices.

DESCRIPTION OF SYMBOLS 1 Crystal resonator 2 Sealing member 20 Recessed part 21 Inner bottom face (recessed part)
200 One main surface 201 Other main surface 3 Crystal vibrating element 4 Lid 6 Through electrode 60 Hole 61 Inner side surface 62 Hole bottom surface 63 Straight pipe portion H Through hole M Conductive member R Resist film D1 Laser beam diameter D2 Bottomed hole opening diameter S Area near one main surface

Claims (4)

A method of manufacturing a sealing member of a piezoelectric vibration device that hermetically seals an excitation electrode of a piezoelectric vibration element,
A through hole forming step of forming a through hole for electrically connecting the two main surfaces of the base material of the sealing member; and a conductive member forming step of forming a conductive member in the through hole. ,
The through-hole forming step is a first step of forming holes on the two main surfaces each having an opening diameter smaller than the opening diameters on the two main surfaces of the base material and having tapered inner surfaces. When,
A second step of forming a through hole by drilling from a position apart from the vicinity of both main surfaces of the inner surface;
A method for manufacturing a sealing member for a piezoelectric vibration device, comprising:   The method for manufacturing a sealing member of a piezoelectric vibration device according to claim 1, wherein the hole in the first step is formed by a wet etching method.   The method for manufacturing a sealing member for a piezoelectric vibration device according to claim 1, wherein, in the second step, the perforation is performed by a beam or blast.   A piezoelectric vibration element on which an excitation electrode is formed is mounted on a sealing member obtained by the method for manufacturing a sealing member for a piezoelectric vibration device according to any one of claims 1 to 3, and the excitation electrode is mounted on the sealing member. Piezoelectric vibration device hermetically sealed with a sealing member.

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