JP2008164472A - Qcm sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact QCM sensor having detecting and comparing piezoelectric oscillators, and measuring the minute quantity of a sample liquid. <P>SOLUTION: In the QCM sensor, an exciting electrode pattern 2 provided in the piezoelectric oscillator 1 is connected to a wiring pattern 4 provided on a substrate 3 by using a connecting material. The QCM sensor is sealed between the periphery of the piezoelectric oscillator and the substrate by a sealant. The detecting piezoelectric oscillator is disposed on one surface of the substrate 3. The comparing piezoelectric oscillator is disposed on the other surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention detects the component of the sample adsorbed on the surface of the electrode pattern from the change in electrical characteristics such as the oscillation frequency and impedance of the piezoelectric vibrator when the electrode pattern on the piezoelectric vibrator is exposed to the sample gas or sample solution. The present invention relates to a mounting structure of a QCM (Quartz Crystal Microbalance) sensor to be quantified.

  In recent years, chemical biosensors using a microbalance principle using a piezoelectric vibrator have attracted attention. The structure of a conventional QCM sensor will be described with reference to FIG. FIG. 11 shows a QCM sensor mounting structure described in Patent Document 1. Excitation electrode patterns 2 a and 2 b are formed on the surface of the piezoelectric vibrator 1. The single-sided covering material 11 covers one surface of the piezoelectric vibrator 1 while holding it, and the side wall inner surface 11 a of the single-sided covering material 11 is in contact with the side face of the piezoelectric vibrator 1. A sealing material 6 is provided between the side wall inner surface 11 a and the piezoelectric vibrator 1, and is adhered to the side wall inner surface 11 a and the outer peripheral portion of the piezoelectric vibrator 1. The electrode patterns 2a and 2b are connected to lead terminals 10a and 10b. The lead terminals 10a and 10b are wired in an airtight space constituted by the single-sided covering material 11 and the piezoelectric vibrator 1, and the lead terminals 10a and 10b. Is connected to an external oscillation circuit through an opening (not shown) of the single-sided covering material 11.

The above-mentioned QCM sensor exposes only the surface of the piezoelectric vibrator 1 on which the electrode pattern 2a is formed, exposes this face to a sample gas or sample liquid, and applies the sample component to the electrode pattern 2a formed on the piezoelectric vibrator 1. It is possible to detect and quantify the sample component from the amount of change in the resonance frequency that fluctuates due to adsorption and desorption.
JP 2001-153777 A (page 4, FIG. 1)

  The QCM sensor described above has the following problems.

  A conventional QCM sensor has a structure in which a piezoelectric vibrator provided with an electrode pattern is arranged on a lead terminal arranged on a single-sided covering material. When a plurality of piezoelectric vibrators are arranged, the piezoelectric vibrators are arranged adjacent to each other. There was a need to do.

  For this reason, when the QCM sensor is enlarged and the entire piezoelectric vibrator is immersed in the sample liquid, a large container body for storing the sample liquid is required. That is, a large amount of sample liquid is required, which is very inconvenient.

  An object of the present invention is to provide a QCM sensor that has a piezoelectric vibrator for detection and a comparison, and is very compact and capable of measuring even when the amount of sample liquid is very small.

  In order to achieve the above object, the QCM sensor according to the present invention employs the following configuration.

In the QCM sensor of the present invention, an excitation electrode pattern provided on a piezoelectric vibrator is connected to a wiring pattern provided on a substrate using a connecting material, and a sealing material is provided between the outer periphery of the piezoelectric vibrator and the substrate. The QCM sensor is sealed with a piezoelectric transducer for detection on one surface of a substrate and a piezoelectric transducer for comparison on the other surface. .

The QCM sensor of the present invention is a QCM sensor in which an excitation electrode pattern provided on a piezoelectric vibrator is connected to a wiring pattern provided on a substrate by using a connecting material, and a detection surface is provided on one surface of the substrate. A piezoelectric vibrator is arranged, a piezoelectric vibrator for comparison is arranged on the other surface, and the periphery of the connection material in the piezoelectric vibrator and the substrate are sealed with a sealing material, and the piezoelectric vibrator for detection And a piezoelectric vibrator for comparison have a space open to the outside.

  In the QCM sensor of the present invention, an excitation electrode pattern provided on a piezoelectric vibrator is connected to a wiring pattern provided on a substrate using a connecting material, and a sealant is provided between the outer peripheral portion of the piezoelectric vibrator and the substrate. A sealed QCM sensor is characterized in that a piezoelectric vibrator for detection is arranged on one surface of a substrate and a piezoelectric vibrator for comparison is arranged on the other surface. .

  By adopting this structure, it is possible to obtain a very compact QCM sensor despite having two piezoelectric vibrators for detection and comparison. Furthermore, accurate measurement can be performed by having a comparative piezoelectric vibrator.

  Also, in the case of a structure having a gap between the detection and comparison piezoelectric vibrators, the sample liquid can be sucked into the gap by capillary action, and this gap becomes a container for the sample liquid, and a very small amount of sample liquid Measurement is possible.

  A very compact QCM sensor can be obtained with a simple structure while having a piezoelectric vibrator for detection and comparison, and a QCM sensor capable of measurement even when the amount of sample liquid is very small can be obtained.

(First embodiment)
Hereinafter, a QCM sensor according to an optimal embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a cross-sectional view of the QCM sensor in the first embodiment of the present invention. As shown in FIG. 1, an excitation electrode pattern 2 provided on the piezoelectric vibrator 1 is connected to a wiring pattern 4 provided on the substrate 3 using a connecting material 5, and the outer periphery of the piezoelectric vibrator 1 and the substrate 3 are connected. A QCM sensor in which a gap is sealed with a sealing material 6, and a detection piezoelectric vibrator 1 is disposed on one surface of a substrate 3, and a comparative piezoelectric vibrator is disposed on the other surface. 1 is arranged. In the present embodiment, when the piezoelectric vibrator 1 disposed on one surface of the substrate 3 is used as the detection piezoelectric vibrator 1, the piezoelectric vibrator 1 disposed on the other surface of the substrate 3 is used. A piezoelectric vibrator 1 for comparison may be used.

  By adopting this structure, it is possible to obtain a very compact QCM sensor despite having two piezoelectric vibrators for detection and comparison. Furthermore, by having the piezoelectric vibrator 1 for comparison, it is possible to perform measurement with high accuracy.

  Next, a method for manufacturing the QCM sensor in the first embodiment will be described with reference to FIGS. First, as shown in FIG. 2, the piezoelectric vibrator 1 is divided into an arbitrary size by a method such as etching or dicing, and a metal thin film is formed on the quartz plate by a sputtering method or a vacuum evaporation method using a metal mask. Thus, an excitation electrode pattern 2 is formed on the piezoelectric vibrator 1.

FIG. 3 is a perspective view of the piezoelectric vibrator 1, and the dotted line represents the state of the back surface. The excitation electrode pattern 2 is formed such that the portion that is electrically connected to the wiring pattern 4 provided on the substrate 3 is on the same surface.

Using a crystal plate as a piezoelectric vibrator 1 in this embodiment, the size is use a thickness of 50μm at 10 mm ^2, 0.1 [mu] m chrome base in a pattern as the excitation portion of the electrode pattern becomes 5 mm ² The gold was formed on the chrome with a thickness of 0.2 μm.

  Next, as shown in the cross-sectional view of FIG. 4, a copper foil is bonded onto the substrate 3 formed of glass or glass fiber and an epoxy resin, and the wiring pattern 4 is formed on the front and back of the substrate 3 by photolithography and etching. Nickel and gold are formed on the surface of the wiring pattern 4 to prevent copper corrosion.

  In this embodiment, a substrate 3 made of glass fiber having a thickness of 0.5 mm and an epoxy resin is used, and a copper foil having a thickness of 18 μm is bonded to form a wiring pattern 4 by photolithography and etching. The surface of the wiring pattern 4 was formed by plating with a thickness of 1 μm nickel and 0.3 μm gold.

  As shown in the sectional view of FIG. 5, a connection made of a conductive adhesive or solder paste for electrically connecting the electrode pattern 2 formed on the piezoelectric vibrator 1 and the wiring pattern 4 formed on the substrate 3. A sealing material 6 made of epoxy, silicone, urethane, or the like that seals the outer peripheral portion of the connection portion between the material 5 and the electrode pattern 2 provided on the piezoelectric vibrator 1 and the wiring pattern 4 provided on the substrate is applied by a dispenser. .

  At this time, the sealing material 6 is applied to the inside of the outer shape of the piezoelectric vibrator 1 with a width of about 200 μm using a dispenser as shown in the plan view of FIG.

  In this embodiment, a conductive adhesive containing silver particles in a silicone adhesive that is soft after curing and does not generate stress that deforms the piezoelectric vibrator 1 is used as the connection material 5. For the same reason, a thermosetting silicone adhesive was used.

  After the connection material 5 and the sealing material 6 are disposed, the piezoelectric vibrator 1 is aligned and disposed on the substrate 3, and then the connection material 5 and the sealing material 6 are cured, whereby the QCM sensor shown in FIG. Is obtained.

(Second embodiment)
Next, a second embodiment will be described. FIG. 7 shows a cross-sectional view of the QCM sensor in the second embodiment of the present invention. As shown in FIG. 7, a QCM sensor in which an excitation electrode pattern 2 provided on a piezoelectric vibrator 1 is connected to a wiring pattern 4 provided on a substrate 3 using a connection material 5, The detection piezoelectric vibrator 1 is disposed on the surface, the comparison piezoelectric vibrator 1 is disposed on the other surface, and the sealing material 6 is disposed between the piezoelectric vibrator 1 around the connecting material 5 and the substrate 3. The portion where the piezoelectric vibrator 1 and the substrate 3 overlap is the periphery of the connection portion between the electrode pattern 2 and the wiring pattern 4. In the present embodiment, when the piezoelectric vibrator 1 disposed on one surface of the substrate 3 is used as the detection piezoelectric vibrator 1, the piezoelectric vibrator 1 disposed on the other surface of the substrate 3 is used. A piezoelectric vibrator 1 for comparison may be used.

  By adopting this structure, it is possible to obtain a very compact QCM sensor despite having two piezoelectric vibrators for detection and comparison. Furthermore, by having the piezoelectric vibrator 1 for comparison, it is possible to perform measurement with high accuracy.

In addition, since there is a gap between the two piezoelectric vibrators 1, the sample liquid can be sucked into the gap by a capillary phenomenon, and can be detected and detected. This eliminates the need for a container or the like for containing the sample liquid.

  Next, a method for manufacturing the QCM sensor in the second embodiment will be described with reference to FIGS. 2 to 3 and FIGS. 8 to 10. First, as shown in FIG. 2, the piezoelectric vibrator 1 is divided into an arbitrary size by a method such as etching or dicing, and a metal thin film is formed on the quartz plate by a sputtering method or a vacuum evaporation method using a metal mask. Thus, an excitation electrode pattern 2 is formed on the piezoelectric vibrator 1.

  FIG. 3 is a perspective view of the piezoelectric vibrator 1, and the dotted line represents the state of the back surface. The excitation electrode pattern 2 is formed such that the portion that is electrically connected to the wiring pattern 4 provided on the substrate 3 is on the same surface.

Using a crystal plate as a piezoelectric vibrator 1 in this embodiment, the size is use a thickness of 50μm at 10 mm ^2, 0.1 [mu] m chrome base in a pattern as the excitation portion of the electrode pattern becomes 5 mm ² The gold was formed on the chrome with a thickness of 0.2 μm.

  Next, as shown in the cross-sectional view of FIG. 8, a copper foil is bonded onto the substrate 3 formed of glass or glass fiber and epoxy resin, and the wiring pattern 4 is formed on the front and back of the substrate 3 by photolithography and etching. Nickel and gold are formed on the surface of the wiring pattern 4 to prevent copper corrosion.

  In this embodiment, a substrate 3 made of glass fiber having a thickness of 0.5 mm and an epoxy resin is used, and a copper foil having a thickness of 18 μm is bonded to form a wiring pattern 4 by photolithography and etching. The surface of the wiring pattern 4 was formed by plating with a thickness of 1 μm nickel and 0.3 μm gold.

  As shown in the cross-sectional view of FIG. 9, a connection made of a conductive adhesive or solder paste for electrically connecting the electrode pattern 2 formed on the piezoelectric vibrator 1 and the wiring pattern 4 formed on the substrate 3. The material 5 is applied on the wiring pattern 4.

  In the present embodiment, a conductive adhesive containing silver particles is used as the connection material 5 which is soft after curing and does not generate stress that deforms the piezoelectric vibrator 1.

  As shown in the sectional view of FIG. 10, after the piezoelectric vibrator 1 is aligned with the substrate 3 and disposed on the substrate 3, the electrode material 2 provided on the piezoelectric vibrator 1 is cured by curing the connecting material 5. And a wiring pattern 4 provided on the substrate 3 are electrically connected.

  A QCM sensor as shown in FIG. 7 can be obtained by pouring the sealing material 6 between the piezoelectric vibrator 1 and the substrate 3 so that the connecting material 5 is completely insulated and curing it.

  In this embodiment, a silicone adhesive that is soft after curing and does not generate stress that deforms the piezoelectric vibrator 1 is used as the sealing material 6.

  The QCM sensor obtained by the above method has a structure having a gap between the piezoelectric vibrator 1 for detection and the comparison, and the sample liquid can be sucked into the gap by capillary action. It becomes a container for sample liquid, and measurement with a small amount of sample liquid is possible.

It is sectional drawing which shows the QCM sensor in 1st embodiment of this invention. It is sectional drawing which shows the manufacturing process of the QCM sensor in 1st embodiment of this invention. It is a perspective view which shows the manufacturing process of the QCM sensor in 1st embodiment of this invention. It is sectional drawing which shows the manufacturing process of the QCM sensor in 1st embodiment of this invention. It is sectional drawing which shows the manufacturing process of the QCM sensor in 1st embodiment of this invention. It is a top view which shows the manufacturing process of the QCM sensor in 1st embodiment of this invention. It is sectional drawing which shows the QCM sensor in 2nd embodiment of this invention. It is sectional drawing which shows the manufacturing process of the QCM sensor in 2nd embodiment of this invention. It is sectional drawing which shows the manufacturing process of the QCM sensor in 2nd embodiment of this invention. It is sectional drawing which shows the manufacturing process of the QCM sensor in 2nd embodiment of this invention. It is sectional drawing which shows the QCM sensor in a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Piezoelectric vibrator 2 Electrode pattern 3 Substrate 4 Wiring pattern 5 Connection material 6 Sealing material 10 Lead terminal 11 Single-sided coating material

Claims (2)

A QCM in which an excitation electrode pattern provided on a piezoelectric vibrator is connected to a wiring pattern provided on a substrate using a connecting material, and a gap between the outer periphery of the piezoelectric vibrator and the substrate is sealed with a sealing material. A sensor,
A QCM sensor in which a detection piezoelectric vibrator is arranged on one surface of the substrate and a comparison piezoelectric vibrator is arranged on the other surface. A QCM sensor in which an excitation electrode pattern provided on a piezoelectric vibrator is connected to a wiring pattern provided on a substrate using a connection material,
A detection piezoelectric vibrator is arranged on one surface of the substrate, and a comparative piezoelectric vibrator is arranged on the other surface, and the space between the connection material in the piezoelectric vibrator and the substrate is sealed. A QCM sensor sealed with a stopper and having a space open to the outside between the detection piezoelectric vibrator and the comparison piezoelectric vibrator.

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