JP2014192782A - Sealing member, sealing auxiliary member, sealing method and sealing auxiliary method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing member, a sealing auxiliary member, a sealing method and a sealing auxiliary method, which suppress deterioration in characteristics of an acoustic wave device within an allowable limit and can seal a desired portion on a substrate.SOLUTION: A sealing member includes: an enclosure which is included in an acoustic wave device reflecting the propagation characteristics of a propagation path of a surface acoustic wave or a bulk wave to a response and circumferentially formed at a region of a surface of a substrate interposed in the propagation path, as a photoresist; a support which is formed, as the photoresist, together with the enclosure at the inside of the region of the surface; and a lid which is formed, as the photoresist, together with the enclosure and the support and covered and brought into contact with the whole of the top of the enclosure. The enclosure, the support and the lid are integrally formed by subjecting the photoresist to curing treatment.

Description

  The present invention provides a sealing member formed as a photoresist and used for sealing a portion on the surface of a substrate interposed in a propagation path of a surface acoustic wave or a bulk wave in an acoustic wave device, and formed as a photoresist. And it is related with the sealing auxiliary member which implement | achieves sealing integrally with the sealing member, and the sealing method and sealing auxiliary method which are each manufacturing methods of these sealing member and sealing auxiliary member.

A transmitting electrode and a receiving electrode are formed on a substrate of a SAW (Surface Acoustic Waves) device, and a propagation path is formed between the transmitting electrode and the receiving electrode.
On such a propagation path, most of the energy of the propagating elastic wave is concentrated on the surface or a very shallow portion below the surface.

  Therefore, the SAW device is applied as a sensor for measuring the amount and components of a solution or the like in contact with the surface as a propagation speed or phase according to the change in the elastic coefficient of the surface of the propagation path, and particularly as a biological sensor. It is being utilized.

FIG. 6 is a diagram illustrating a configuration example of a conventional SAW sensor.
A conventional SAW sensor is manufactured through the following steps as shown in FIG.

(1) A dam 42S (42R) is surrounded by a photoresist (SU8) around a specific portion (a transmitting electrode 41S and a receiving electrode 41R are respectively formed) on the surface of the substrate 40. It is formed. Here, the surface acoustic wave propagation path 43 is formed in a region sandwiched between the transmitting electrode 41S and the receiving electrode 41R in the surface of the substrate 40.

(2) Curing is achieved by heating these dams 42S (42R).
(3) On the top of the dam 42S (42R), a glass cap 44S (44R) suitable for the shape and size of the top is placed, and the dam 42S (42R) is integrated with an adhesive. It is done.

  That is, the transmission electrode 41S is sealed by a pair of an integrated dam 42S and a cap 44S, and the transmission electrode 41R is similarly sealed by a pair of an integrated dam 42R and a cap 44R. The

Further, the transmission electrode 41S and the reception electrode 41R are physically separated from the propagation path 43.
Therefore, a short circuit caused by direct contact of the solution or the like with the transmitting electrode 41S or the receiving electrode 41R, or deterioration in characteristics or accuracy is avoided.

  The above steps (1) to (3) are performed in parallel for a plurality of SAW sensors arranged in a lattice pattern on the wafer, and the wafer is finally diced, so that these SAW sensors Individually chipped.

  In addition, as a prior art relevant to the present invention, as disclosed in Patent Document 1 to be described later, “a device substrate having a main surface formed with a piezoelectric element and a conductive pattern connected to the piezoelectric element; A support layer disposed around the piezoelectric element on the principal surface of the element substrate, and the element substrate when disposed on the support layer and viewed from a normal direction of the principal surface of the element substrate. The inner side is removed from the outer periphery of the element substrate, the cover extending from the outer periphery of the element substrate to the outer periphery and the outer periphery of the element substrate at intervals, and the cover side from the element substrate. An insulating reinforcing material that covers the entire area from the cover to the periphery of the main surface of the element substrate, and a conductive member that is electrically connected to the conductive pattern and penetrates the cover and the reinforcing material. " It is possible to improve moisture resistance, there is a piezoelectric device is characterized in the sealing need not be "points after mounting on a circuit board.

Japanese Patent No. 4210958

  By the way, in the conventional SAW sensor described above, due to the following factors, the cost is high, and there is a possibility that deviations may occur in reliability and performance.

(1) Both the mounting of the cap 44S (44R) on the top of the dam 42S (42R) and the bonding between them must be performed one by one.
(2) Each of the caps 44S (44R) is expensive because the glass plate is separately formed into individual pieces, and the manufacturing process is complicated, and the cost tends to be high.

(3) Since the top of the dam 42S (42R) to which the cap 44S (44R) is to be bonded is fine, when the dam 42S (42R) is chipped, the transmitting electrode 41S and the receiving electrode 41R The possibility of incomplete sealing was high.
(4) Eliminating such chipping requires additional man-hours.

  The present invention provides a sealing member, a sealing auxiliary member, a sealing method, and a sealing auxiliary method capable of sealing a desired portion on a substrate while suppressing deterioration of characteristics of an elastic wave device within an allowable limit. With the goal.

  In the sealing member according to claim 1, the enclosure is provided in an acoustic wave device that reflects a propagation characteristic of a propagation path of a surface acoustic wave or a bulk wave in a response, and is formed on a surface of a substrate interposed in the propagation path. Around the part, it is provided as a photoresist. The support is formed as the photoresist together with the enclosure on the inside of the portion of the surface. The lid body is formed as the photoresist together with the enclosure body and the support body, and is attached to and touches all the top portions of the enclosure body. The enclosure, the support, and the lid are integrated by curing the photoresist.

  That is, in the acoustic wave device to which the present invention is applied, not only the enclosure and the support but also the lid is formed on the substrate as a photoresist. Further, when the ratio of the size of the opening at the top of the enclosure and the height of the enclosure is large, the lid does not come into contact with the substrate by the support, although it may sag.

  The sealing auxiliary member according to claim 2, wherein the enclosure is provided in an elastic wave device that reflects a propagation characteristic of a propagation path of a surface acoustic wave or a bulk wave in a response, and the surface of the substrate interposed in the propagation path This region is provided as a photoresist. The support is formed as the photoresist together with the enclosure on the inside of the portion of the surface.

  That is, the sealing auxiliary member according to the present invention includes the enclosure and the above-described case even when the lid to be placed on the top of the enclosure is formed as a photoresist for internal sealing. As a result of the process of forming both of the supports on the substrate as a photoresist, the support is a target for delivery to the subsequent process.

  In the sealing method according to claim 3, a surrounding body and a projecting support body are provided on each of an outer periphery and an inner portion of a specific portion of the surface of the substrate on which the surface acoustic wave or the bulk wave propagates. Formed as. A lid that contacts all of the top of the enclosure is formed as the photoresist, and the enclosure, the support, and the lid are integrated by curing the photoresist.

  That is, in the acoustic wave device to which the present invention is applied, not only the enclosure and the support but also the lid is formed on the substrate as a photoresist. Further, when the ratio of the size of the opening at the top of the enclosure and the height of the enclosure is large, the lid does not come into contact with the substrate by the support, although it may sag.

  In the sealing auxiliary method according to claim 4, a surrounding body and a projecting support body are respectively provided on the outer periphery and the inside of a specific portion of the surface of the substrate on which the surface acoustic wave or the bulk wave propagates. It is formed as a resist.

  That is, the sealing auxiliary member according to the present invention includes the enclosure and the above-described case even when the lid to be placed on the top of the enclosure is formed as a photoresist for internal sealing. As a result of the process of forming both of the supports on the substrate as a photoresist, the support is a target for delivery to the subsequent process.

  The elastic wave device to which the present invention is applied is a low-cost property and performance degradation due to the desired part on the substrate being sealed with high accuracy at low cost and the lid being bent and contacting the substrate under a flexible process. Is definitely avoided.

  In addition, in the acoustic wave device to which the present invention is applied, a desired portion on the substrate is sealed with high accuracy at low cost, and characteristics and performance are kept high and stable with low deviation.

  Therefore, in the apparatus to which the present invention is applied, the price / performance ratio and load value are improved by utilizing the acoustic wave device without lowering the overall reliability due to the deterioration of the performance and characteristics of the acoustic wave device. Is planned.

It is a figure which shows one Embodiment of this invention. It is a flowchart figure of the sealing process of the transmitting electrode and receiving electrode in this embodiment. It is a figure which shows the example of arrangement | positioning of the support | pillar in this embodiment. It is a figure explaining the effect | action of this embodiment. It is a figure which shows the other structure of the electrode which can apply this invention. It is a figure which shows the structural example of the conventional SAW sensor.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing an embodiment of the present invention.
In the figure, the same components as those shown in FIG. 6 are given the same reference numerals, and the description thereof is omitted here.

The difference between the present embodiment and the conventional example shown in FIG. 6 is as follows.
(1) A top plate 11S (11R) is provided instead of the cap 44S (44R).
(2) The columns 12S-1 to 12S-5 are disposed on the transmission electrode 41S.
(3) The columns 12R-1 to 12R-5 are disposed on the receiving electrode 41R.

FIG. 2 is a flowchart of the sealing process of the transmitting electrode and the receiving electrode in the present embodiment.
Hereinafter, the operation and effect of this embodiment will be described with reference to FIGS. 1 and 2.
The feature of the present invention is that, in the present embodiment, sealing of the transmitting electrode 41S and the receiving electrode 41R is realized based on the following steps.

(1) The columns 12S-1 to 12S-5 are formed as a photoresist (SU8) together with the dam 42S on the transmission electrode 41S (step S1 in FIG. 2), and the substrates of these columns 12S-1 to 12S-5 The height with respect to the surface of 40 is set to be the same as the height of the dam 42S.

(2) Columns 12R-1 to 12R-5 are formed as a photoresist (SU8) together with the dam 42R on the transmission electrode 41R (step S2 in FIG. 2), and the substrates of these columns 12R-1 to 12R-5 The height with respect to the surface of 40 is set to be the same as the height of the dam 42R.

(3) A SU8 thin plate is mounted flat on the top of the dams 42S, 42R by laminating (step S3 in FIG. 2).

(4) By performing photoetching on the thin plate, the top plates 11S and 11R are formed as photoresists (SU8) on the tops of the dams 42S and 42R, respectively (step S4 in FIG. 2).

(5) Curing and integration are achieved by heating the columns 12S-1 to 12S-5 together with the dam 42S and the top plate 11S (step S5 in FIG. 2).

(6) The struts 12R-1 to 12R-5 are heated together with the dam 42R and the top plate 11R to be cured and integrated (step S6 in FIG. 2).
Note that the steps (1) and (2) may be performed in parallel, or may be performed individually in any order.

  In the SAW sensor having such a configuration, a SU8 top plate 11S (11R) is provided instead of the glass cap 44S (44R) mounted on the top of the dam 42S (42R) in the conventional example.

  Further, these top plates 11S (11R) are integrated with the dam 42S (42R) by the heating described above, and these dams 42S (42R) and the columns 12S-1 to 12S-5 (12R-1 to 12R-) are integrated. Curing is achieved with 5).

  By the way, in the process of laminating and heating described above, the ratio (= “5” to the height (for example, 50 to 200 μm) of the dam 42S (42R) and the longest distance (for example, 1000 to 2000 μm) between the inner walls. As “40”) is smaller, the possibility that the top plate 11S (11R) hangs down to the inside of the dam 42S (42R) increases as shown by the broken line in FIG.

  However, in the present embodiment, the top plate 11S (11R) is in contact with the substrate 40 and the transmission electrode 41S (the reception electrode 41R) by the tops of the columns 12S-1 to 12S-5 (12R-1 to 12R-5). It is supported without doing.

  That is, each of the transmitting electrode 41S (receiving electrode 41R) is composed of a common material SU8, and the columns 12S-1 to 12S-5 (12R-1 to 12R-) which are integrated and cured by heat treatment. According to 5), physical isolation from the propagation path 43 is achieved together with sealing.

  In addition, in this embodiment, by using a common material and adopting a simple and highly accurate manufacturing method by photolithography (photolithography), it is possible to compress performance and characteristic deviations at a significantly lower cost than conventional examples. It is done.

  In the present embodiment, the processes described in steps S1 and S2 in FIG. 2 may be performed in parallel as one process.

  Moreover, in this embodiment, support | pillar 12S-1-12S-5 (12R-1-12R-5) may be formed in a process different from the process in which the dam 42S (42R) is formed.

  Furthermore, in this embodiment, the site where all or part of the processes described in steps S3 to S6 in FIG. 2 are performed is not necessarily the same as the site where the preceding processes (steps S1 and S2 in FIG. 2) are performed. In addition, the intermediate product may be transported or delivered as appropriate at these sites.

  In the present embodiment, the processes described in steps S5 and S6 in FIG. 23 may be performed in parallel as one process.

  Furthermore, in this embodiment, if the mounting of the top plates 11S and 11R is realized with a desired accuracy, the heights of the tops of the dams 42S and 42R on which the top plates 11S and 11R are to be mounted are different. Also good.

In the present embodiment, the top plates 11S and 11R are mounted on the tops of the dams 42S and 42R by laminating a thin plate made of SU8.
However, such mounting of the top plates 11S and 11R may be performed individually by some device, for example.

  Furthermore, in the present embodiment, the columns 12S-1 to 12S-5 (12R-1 to 12R-5) are shown in FIGS. 3A and 3B, for example, if loss and deterioration of characteristics are allowed. As illustrated, it may be arranged in any way with respect to the transmitting electrode 41S (receiving electrode 41R), and any of the shape, size, and material may be set.

  Further, in this embodiment, the columns 12S-1 to 12S-5 (12R-1 to 12R-5) are the transmitting electrode 41S (receiving electrode 41R) or the transmitting electrode 41S (receiving electrode 41R). It may be formed of a material having high compatibility with the plating (for example, gold plating) applied to the surface.

  Furthermore, the present invention is not limited to the case where the transmitting electrode 41S and the receiving electrode 41R are unbalanced electrodes. For example, as shown in FIG. 5, the transmitting electrode 41S and the receiving electrode 41R The same applies to the case of a balanced electrode.

  In such a case, the columns 12S-1 to 12S-5 (12R-1 to 12R-5) are disposed only on the electrodes to be grounded externally, for example, as shown in FIG. May be.

  Further, in the present embodiment, the SU 8 is a photoresist, which can be spin-coated or applied with a desired thickness, and has an appropriate viscosity, the wavelength of light to be applied for exposure, the curing temperature, and the like. Regardless of the difficulty of peeling after curing and the physical strength, various photo-sensitive resist materials can be substituted.

  In the present embodiment, the object to be sealed is not limited to the periphery of the transmitting electrode 41S and the receiving electrode 41R, and may be the entire surface or a part of the propagation path 43, for example.

  Furthermore, the present invention applies not only to SAW devices such as SAW sensors (including SAW solution sensors) and SAW filters, but also to FBAR (Film Bulk Acoustic Resonator) filters and various MEMS (Micro Electro Mechanical System) devices. Applicable.

  Further, the present invention is not limited to the above-described embodiments, and various configurations of the embodiments are possible within the scope of the present invention, and any improvements may be made to all or some of the components.

Hereinafter, among the inventions disclosed in the present application, the configurations, operations, and effects of the inventions not described in the “Claims” are referred to as “Claims”, “Means for Solving the Problems”, “Inventions”. List them in a format consistent with the description in each column.
[Claim 5]
The sealing member according to claim 1,
The acoustic wave device is
A surface acoustic wave filter or a surface acoustic wave biosensor;
The site is
A sealing member, wherein the surface is a portion where an electrode constituting a surface acoustic wave filter or a surface acoustic wave biosensor is formed.

  The sealing member according to claim 5 is the sealing member according to claim 1, wherein the acoustic wave device is a surface acoustic wave filter or a surface acoustic wave biosensor. The said site | part is a site | part in which the electrode which comprises a surface acoustic wave filter or a surface acoustic wave biosensor is formed in the said surface.

  That is, in the surface acoustic wave filter or surface acoustic wave sensor according to the present invention, the electrode is sealed, and the electrode is physically isolated from other parts.

Therefore, both imperfect sealing of the electrode and deterioration of characteristics and performance associated with the sealing can be avoided with high accuracy at low cost.
[Claim 6]
In the sealing member according to claim 1 or 5,
All or part of the shape, size, arrangement, number of the support is
A sealing member characterized in that it is set in a form in which deterioration of characteristics of the acoustic wave device is allowed.

  The sealing member according to claim 6 is the sealing member according to claim 1 or 5, wherein all or part of the shape, size, arrangement, and number of the support are characteristics of the acoustic wave device. It is set to a form in which the deterioration of is allowed.

  That is, according to the sealing member of the present invention, regardless of the size of the opening at the top of the enclosure and the height of the enclosure, the lid mounted on the top is bent to the substrate. Both the contact and the deterioration of the characteristics of the elastic wave device to which the present invention is applied exceed an allowable limit can be avoided with high accuracy.

Therefore, the present invention can be flexibly applied to acoustic wave devices having various configurations and sizes, and contributes to an improvement in price / performance ratio and overall reliability.
[Claim 7]
The sealing member according to claim 2,
The acoustic wave device is
A surface acoustic wave filter or a surface acoustic wave biosensor;
The site is
A sealing auxiliary member, wherein the surface is an area where an electrode constituting a surface acoustic wave filter or a surface acoustic wave biosensor is formed.

  The auxiliary sealing member according to claim 7 is the sealing member according to claim 2, wherein the acoustic wave device is a surface acoustic wave filter or a surface acoustic wave biosensor. The said site | part is a site | part in which the electrode which comprises a surface acoustic wave filter or a surface acoustic wave biosensor is formed in the said surface.

  That is, the surface acoustic wave filter or the surface acoustic wave sensor according to the present invention is not limited to the sealing of the electrode and the physical isolation from the electrode and other parts, although the restrictions on the manufacturing process are relaxed. Is possible flexibly.

Therefore, both imperfect sealing of the electrode and deterioration of characteristics and performance associated with the sealing can be avoided with high accuracy at low cost.
[Claim 8]
In the sealing auxiliary member according to claim 2 or 7,
All or part of the shape, size, arrangement, number of the support is
The sealing auxiliary member is set in a form in which deterioration of characteristics of the acoustic wave device is allowed.

  The sealing auxiliary member according to claim 8 is the sealing auxiliary member according to claim 2 or 7, wherein all or part of the shape, size, arrangement, and number of the support are the acoustic wave device. It is set to a form in which the deterioration of the characteristics of is allowed.

  In other words, the acoustic wave device according to the present invention has a restriction on the manufacturing process alleviated regardless of the size of the opening at the top of the enclosure and the height of the enclosure, and is mounted on the top. Both of the contact of the lid with the substrate and the deterioration of the characteristics exceeding the allowable limit can be avoided with high accuracy.

  Therefore, the present invention can be flexibly applied to acoustic wave devices having various configurations and sizes, and contributes to an improvement in price / performance ratio and overall reliability.

11R, 11S Top plate 12R, 12S Post 40 Substrate 41R Receive electrode 41S Transmit electrode 42R, 42S Dam 43 Propagation path 44R, 44S Cap

Claims (4)

An envelope provided as an photoresist on a portion of the surface of the substrate that is provided in an elastic wave device that reflects the propagation characteristics of a propagation path of a surface acoustic wave or a bulk wave in a response, and is interposed in the propagation path;
A support formed as the photoresist together with the enclosure on the inside of the surface of the surface;
A cover body that is formed as the photoresist together with the enclosure body and the support body and is in contact with the top of the enclosure;
The enclosure, the support and the lid are
A sealing member, which is integrated by a curing process of the photoresist. An envelope provided as an photoresist on a portion of the surface of the substrate that is provided in an elastic wave device that reflects the propagation characteristics of a propagation path of a surface acoustic wave or a bulk wave in a response, and is interposed in the propagation path;
A sealing auxiliary member comprising: a support body formed as the photoresist together with the enclosure on the inner side of the surface of the surface. On the surface of the substrate on which the surface acoustic wave or bulk wave propagates, a surrounding body and a projecting support are formed as a photoresist on the outer periphery and inside of a specific part, respectively,
A lid that contacts all of the top of the enclosure is formed as the photoresist,
The sealing method, wherein the enclosure, the support and the lid are integrated by curing the photoresist. Sealing aid characterized by forming an enclosure and a projecting support as a photoresist on the outer periphery and inside of a specific part of the surface of the substrate on which surface acoustic waves or bulk waves propagate. Method.