JP2007010523A - Sensor for measuring micromass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sensor for measuring micromass of high reliability constituted by incorporating a circuit in a QCM sensor container. <P>SOLUTION: The sensor element for measuring micromass is provided to the QCM sensor container so that only one main electrode surface thereof is exposed and the side surface of the micromass measuring sensor element is placed in the QCM sensor container by an insulating adhesive. Also, the circuit part electrically connected to the signal output terminal of the micromass measuring sensor element is built in the QCM sensor container in the vicinity of the micromass measuring sensor element. Further, the micromass measuring sensor (QCM sensor) container is composed of glass, quartz, a plastic or a ceramic and the signal input/output terminal of the circuit part in the QCM sensor container is extended to the outer surface of the container. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

          The present invention relates to a highly reliable sensor for measuring a minute mass, in which a circuit is incorporated in a liquid phase QCM sensor container.

          Conventionally, a sensor element for measuring a minute mass (QCM: Quartz Crystal Microbalance sensor element) using a crystal resonator has utilized a thickness shear vibration of crystal, and a metal film material formed on a surface of a crystal substrate includes a crystal film. Chromium (Cr), nickel chrome (NiCr), titanium (Ti), etc. are used in consideration of adhesion to the substrate. When the entire sensor element for measuring such a small mass is immersed in the solution The vibration described above is suppressed by the resistance force of the solution and cannot be used as a sensor element for measuring a minute mass. Therefore, it is possible to detect vibration even if the sensor for measuring a minute mass is immersed in the solution by setting the metal film of the quartz substrate on the side not contacting the liquid phase without detecting the reaction of the solution to the gas phase state. .

          In order to keep the metal film on one side of the quartz substrate in a gas phase without being in contact with the liquid phase, the entire periphery of the side surface of the sensor element for measuring the minute mass is fixed with an adhesive or the like to prevent the solution from entering. There must be. In general, in order to make the influence on vibration of the sensor element for measuring a minute mass as small as possible, a silicon-based insulating adhesive having a small bonding stress is often used.

          In addition, a minute change in weight when the reactant to be measured adheres to or separates from the surface of the crystal unit is considered as a frequency change of the crystal unit, but because this reactant attaches to the surface of the crystal unit, Basically, a sensor for measuring minute mass (hereinafter also referred to as a QCM sensor) uses a disposable method. In terms of analysis accuracy, the stability of temperature control and the frequency change amount per unit weight are large. However, there are cases where the desired measurement accuracy cannot be obtained due to the influence of noise.

          In this way, in the measurement using the QCM sensor, the desired measurement accuracy may not be obtained due to the influence of noise. Therefore, in many cases, the analysis device including the oscillator and the QCM sensor element are connected with a connector such as a socket. Through the electrical connection. On the other hand, the purpose of the QCM analyzer is to measure the state of attachment / dissociation of reactants on the surface of the quartz crystal due to ecochemical reactions. Measurement in a controlled environment is required.

JP 2001-153777 A Japanese Patent Laid-Open No. 11-14525

          In addition, the applicant did not find any prior art documents related to the present invention by the time of filing of the present application other than the prior art documents specified by the above prior art document information.

          However, it is of course difficult to immerse the socket part in the temperature-controlled liquid phase reaction phase because an electrical short circuit is caused, and it is located between the QCM sensor and the analyzer. When the physical distance to the oscillation circuit, which is a circuit unit, is long, there is a possibility that the measurement accuracy using the QCM sensor may be significantly reduced due to the influence of electrical noise caused by temperature control or the like.

          The present invention has been made under the technical background as described above. Accordingly, the object of the present invention is to provide a highly reliable small mass in which a circuit is incorporated in a container of a liquid phase QCM sensor. It is to provide a sensor for measurement (QCM sensor).

          In order to achieve the above object, the present invention provides a QCM sensor container in which a sensor element for measuring a minute mass is exposed by QCM using an insulating adhesive on the side of the sensor element for measuring a minute mass with only one main electrode surface exposed. A QCM sensor container includes a circuit unit that is placed in the sensor container and is electrically connected to the signal output terminal of the sensor element for measuring the minute mass in the vicinity of the sensor element for measuring the minute mass.

          Further, the sensor for measuring a minute mass (QCM sensor) is made of glass, crystal, plastic, or ceramic.

          Further, the signal input / output terminal of the circuit part inside the QCM sensor container extends to the outer surface of the container.

          According to the sensor for measuring a minute mass (QCM sensor) according to the present invention, the physical distance from the sensor element for measuring a minute mass using a crystal resonator to a circuit unit such as an oscillation circuit can be shortened. The impact can be significantly reduced.

          In addition, according to the sensor for measuring a minute mass of the present invention, the crystal unit that is the sensor element for measuring the minute mass and the circuit unit can be used in the same container in a temperature environment controlled with high accuracy. In addition, the measurement accuracy of the sensor for measuring minute mass can be remarkably improved.

          Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the same code | symbol in each figure shall show the same object.

          FIG. 1 is a schematic side sectional view of a sensor 12 for measuring a minute mass (QCM sensor 12) of the present invention as viewed from the side. That is, it is a sensor element 4 for measuring a minute mass using a quartz crystal resonator in which a metal film 2 is formed on the surface of a quartz substrate 1, and a QCM sensor element 4 is disposed on a sensor container 5 for measuring a minute mass, on one main electrode surface. 6 is exposed to the liquid phase side, and is placed in the sensor container 5 for measuring the minute mass by the insulating adhesive 8 on the side surface 7 of the QCM sensor element, and the signal of the QCM sensor element 4 is immediately adjacent to the QCM sensor element 4. The circuit unit 10 electrically connected to the output end is built in the QCM sensor container 5. According to the QCM sensor 12 of the present invention, the physical distance from the minute mass measurement sensor (QCM sensor) element 4 using a crystal resonator to the circuit unit 10 such as an oscillation circuit can be made much shorter than before. And the effect of external noise can be significantly reduced.

          FIG. 2 is a schematic top view of the QCM sensor 12 of the present invention as viewed from the direction of one main surface where the sensor element 4 for measuring a minute mass is exposed. Due to the shape as shown in the figure, an effect is obtained in that an operator puts his / her finger on the left and right protruding portions and the insertion / removal of the QCM sensor 12 of the present invention into the connector is remarkably simplified. In addition, the hollow of the cylindrical portion of the QCM sensor 12 of the present invention is to keep the metal film 2 on one side of the sensor element 4 for measuring a minute mass in a gas phase without contacting the liquid phase, and to prevent the liquid phase from entering the solution. Although it is necessary to fix and close the entire periphery of the side surface 7 of the QCM sensor element with an adhesive or the like, the QCM sensor element side surface 7 is fixed and placed in the sensor container 5 for measuring a minute mass using the insulating adhesive 8. This is provided to remove the gas generated from the insulating adhesive 8 during the process.

          FIG. 3 is a schematic top view of the micromass measuring sensor element 4 as viewed from the direction of one exposed main surface, showing the connector 14 connected to the QCM sensor 12 of the present invention. In the QCM sensor 12 of the present invention, the signal input / output end 9 of the circuit unit 10 inside the QCM sensor container 5 is extended to the outer surface of the container 5 in order to improve the efficiency of measurement work using the QCM sensor 12. For this reason, the QCM sensor 12 can be quickly attached to and detached from the connector 14.

          FIG. 4 is a schematic diagram showing the configuration of a measurement system using a crystal resonator in the QCM sensor element of the present invention compared with the configuration of a measurement system using a crystal resonator in a conventional QCM sensor element. According to the present invention, it is possible to use the crystal resonator which is the QCM sensor element 4 and the circuit unit 10 in the same container in a temperature environment controlled with high accuracy as shown in the schematic diagram of FIG. Therefore, the measurement accuracy can be remarkably improved.

          FIG. 5 is a schematic side sectional view of a conventional sensor element 4 for measuring a minute mass as viewed from the side.

          FIG. 6 is a schematic top perspective view of a conventional sensor element 4 for measuring a small mass as seen from an oblique top surface direction. Conventionally, when the physical distance to the oscillation circuit which is the circuit unit 10 located in the middle between the single QCM sensor 12 using the sensor element 4 for measuring a minute mass as shown in FIG. There is a possibility that the measurement accuracy using the QCM sensor 12 may be remarkably lowered under the influence of electrical noise caused by temperature control or the like and the ambient temperature.

It is the side sectional view of the outline which looked at the sensor for minute mass measurement (QCM sensor) of the present invention from the side. FIG. 3 is a schematic top view of the QCM sensor of the present invention as viewed from the direction of one main surface where a sensor element for measuring a minute mass is exposed. It is a schematic top view as seen from the direction of one exposed main surface of the sensor element for measuring a minute mass, showing a state where the connector is connected to the QCM sensor of the present invention. It is the schematic which shows the structure of the measurement system using the QCM sensor of this invention compared with the structure of the measurement system using the conventional QCM sensor. It is the general side sectional view which looked at the conventional sensor element for micro mass measurement from the side direction. It is the general | schematic upper surface perspective view which looked at the conventional sensor element for micro mass measurement from the diagonal upper surface direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Crystal substrate 2 Metal film 4 Sensor element 5 for minute mass measurement Sensor container 6 for minute mass measurement Main electrode surface 7 Sensor element side surface 8 for minute mass measurement Insulating adhesive 9 Signal input / output terminal 10 Circuit unit 11 For minute mass measurement External surface 12 of sensor element container Sensor 14 for measuring minute mass Connector

Claims (3)

In a sensor element for measuring micro mass using a crystal resonator formed by forming a metal film on the surface of a quartz substrate,
Only one main electrode surface of the sensor element for measuring the minute mass is exposed to the sensor container for measuring the minute mass, and the inside of the sensor container for measuring the minute mass with an insulating adhesive on the side of the sensor element for measuring the minute mass And a circuit part electrically connected to the signal output terminal of the sensor element for measuring the minute mass in the vicinity of the sensor element for measuring the minute mass is incorporated in the sensor container for measuring the minute mass Sensor for mass measurement.           2. The sensor for measuring micro mass according to claim 1, wherein the sensor container for measuring micro mass is made of glass, quartz, plastic, or ceramic.           2. The sensor for measuring a minute mass according to claim 1, wherein a signal input / output terminal of a circuit portion inside the sensor container for measuring a minute mass extends to an outer surface of the container.

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