KR20070111648A - Sensor module and capsule type medical device including the same - Google Patents

Abstract

A sensor module and a capsule type medical device having the same are provided to measure potential of hydrogen accurately by isolating a reference electrode from a liquid to be measured. A sensor module includes a board(11), a pressure sensor(12), a first housing(18), and a filler(13). The pressure sensor is arranged on the board. The first housing is coupled with the board and encloses the pressure sensor. A first aperture for delivering an external pressure into the first housing is formed on the first housing. The filler is filled between the pressure sensor and the first housing. The viscous filler delivers the pressure from the first aperture to the pressure sensor. The first aperture has a slit-like shape.

Description

Sensor module and capsule type medical device including same {sensor module and capsule type medical device including the same}

1 is a view showing a plan view of a sensor module 10 according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1.

3 is a view showing a capsule-type medical device according to an embodiment of the present invention.

4 is a cross-sectional view taken along the line B-B 'of FIG.

* Explanation of the main symbols in the drawings *

11, 56: substrate 12: pressure sensor

13: Filler 14: Ion Sensing Field Effect Transistor

15 metal reference electrode 16 reference solution

17: porous ceramics 18, 19, 20: housing

21, 22, 23, 24: opening 31: source region

32: drain region 33: channel region

34: insulating film 35: hydrogen ion detection film

36 source electrode 37 drain electrode

40: exterior member 51: amplification unit

52: CPU 53: Memory

54: transmitter 55: battery

57: wire

The present invention relates to a sensor module and a capsule-type medical device including the same. More specifically, the pressure or hydrogen ion concentration index (hereinafter simply referred to as pH) can be more accurately measured in a harsh environment including acids, bases, foods, and the like. It is to provide a sensor module and a capsule-type medical device including the same.

Capsule-type medical device is used for the purpose of examination or treatment, and means a capsule-type medical device that can be inserted into the body. BACKGROUND OF THE INVENTION Capsule-type medical devices have recently been widely researched for the purpose of replacing endoscopy giving a sense of rejection, obtaining information on an accurate organ, or treating an organ without performing surgery.

There is a technique disclosed in Korean Laid-Open Publication No. 10-2006-0002449 as a prior art of a capsule medical device. The publication discloses a capsule endoscope comprising sensors for collecting information (image sensor, acceleration sensor, temperature sensor, pressure sensor and pH sensor) and a transmitter for transmitting the collected information to the outside. However, this publication does not describe the specific structures of the pressure sensor and the pH sensor.

For the measurement, the pressure sensor and the pH sensor should be exposed to digestive fluids and foods as an external example of the capsule-type medical device, and thus there is a problem that the accuracy of the measurement may be degraded due to digestive fluids and foods. More specifically, the Ag / AgCl electrode, which may be used as a reference electrode of the pH sensor, may be insoluble in a strong acid such as gastric juice and pass through the gastrointestinal tract, thereby reducing the accuracy of the pH sensor measurement. In addition, when the pressure sensor is directly in contact with the large intestine or the small intestine, the shock caused by the peristalsis movement of the large intestine or the small intestine is transmitted to the pressure sensor as it is, and the accuracy of the measurement is reduced. It may be destroyed and impossible to measure. In addition, when the wiring or the electrode of the pressure sensor is exposed to the extinguishing fluid or food, the accuracy of the measurement may be lowered due to noise or the like. Therefore, there is a need for the development of a sensor module having a structure that can solve this problem and a capsule-type medical device including the same.

Accordingly, the technical problem to be achieved by the present invention is to solve the above problems, and to provide a sensor module and a capsule-type medical device including the same, the accuracy of the measurement even when exposed to acidic or basic digestive fluid and food.

As a technical means for achieving the above object, the first aspect of the present invention is a substrate; A pressure sensor located on the substrate; A first housing coupled to the substrate to seal the pressure sensor, the first housing having at least one first opening configured to transmit external pressure therein; And a flowable filler filled between the pressure sensor and the first housing and transferring the pressure transferred to the pressure sensor through the first opening.

A second aspect of the invention is a substrate; An ISFET positioned on the substrate and including a source, a drain, a channel, an insulating film, and a hydrogen ion sensing film; A metal reference electrode on the substrate; A first housing coupled to the substrate to seal the ISFET and the metal reference electrode and having first and second openings formed therein; A second housing filled between the first housing and the ISFET, the second housing having a third opening to expose the hydrogen ion sensing film together with the first opening; A porous ceramic filled in the second opening; And a reference solution filled between the porous ceramic and the metal reference electrode.

A third aspect of the present invention is a capsule type medical device including a sensor module and an outer member which is combined with the sensor module to form a capsule, wherein the sensor module is any one of the first to second aspects of the present invention. It provides a capsule-type medical device that is a sensor module.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the present invention may be modified in various forms, the scope of the present invention should not be construed in a way that is limited by the embodiments described below. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

1 is a view showing a plan view of the sensor module 10 according to an embodiment of the present invention, Figure 2 is a view showing a cross-sectional view taken along line AA 'of FIG.

1 and 2, the sensor module includes a substrate 11, a pressure sensor 12, a filler 13, an ion sensitive field effect transistor (hereinafter simply referred to as an ISFET) 14, Metal reference electrode 15, reference solution 16, porous ceramic 17, and first to third housings 18, 19, 20. A first opening 21 is formed in the first housing 18, and a third opening 23 in which the second opening 22 and the porous ceramic 17 are located is formed in the second housing 19. . The fourth opening 24 is formed in the third housing 20.

The substrate 11 may be, for example, a printed circuit board (hereinafter, simply referred to as a PCB).

The pressure sensor 12 is located on the substrate and may be any pressure sensor that can be miniaturized. The pressure sensor 12 may be, for example, a piezoresistive pressure sensor or a capacitive pressure sensor.

The filling 13 is filled between the first housing 18 and the pressure sensor 12, is fluid, and receives the pressure transmitted to the inside of the first housing 18 through the first opening 21. To 12). The filling material is preferably an insulating oil having a relatively high viscosity so as not to leak to the outside through the first opening 21, and may be, for example, silicone oil.

The first housing 18 is coupled to the substrate 11 to seal the pressure sensor 12, and at least one first opening 21 to transfer pressure from the outside of the sensor module 10 to the inside of the sensor module 10. Is formed. One first opening 21 may be formed in the first housing 18 as shown in the drawing, or a plurality of first openings 21 may be formed. Preferably, the first opening 21 has a slit shape so that external pressure is well transmitted to the inside and the filling 13 is not leaked to the outside. In addition, it is preferable that the width of the first opening portion 21 is 0.5 to 2 mm. When the sensor module 10 is used in a capsule medical device, since the first housing 18 is exposed to the outside of the capsule medical device, it must be harmless to the human body and chemically stable. The first housing 18 may be made of, for example, teflon.

As the pressure sensor 12 is protected by the filler 13 and the first housing 18 as described above, the pressure sensor 12 can be accurately measured pressure while being protected from external shock and not exposed to the extinguishing liquid or the like. .

The ISFET 14 includes a source region 31, a drain region 32, a channel region 33, an insulating film 34, and a hydrogen ion sensing film 35. As shown in the drawing, the channel region 33 may be a silicon substrate doped with a P-type, and the source region 31 and the drain region 32 may be a region doped with an N + type. The source electrode 36 is connected to the source region 31, and the drain electrode 36 is connected to the drain region 32. The insulating layer 34 is formed on the channel region and may be, for example, an oxide layer SiO ₂ . The hydrogen ion sensing film 35 plays a role of generating a potential difference corresponding to the concentration of hydrogen ions (H ⁺ ) of the solution to be measured (digestion, etc.) in contact with it. This potential difference is known to follow the Nernst equation. The hydrogen ion sensing layer 35 may be formed of, for example, Ta ₂ O ₅ , SiO ₂ , Si ₃ N ₄ , PtO ₂ , IrO ₂ , RuO ₂ , Al ₂ O _3, or ZrO ₂ . The hydrogen ion sensing layer 35 is positioned on the insulating layer 34.

The metal reference electrode 15 performs a function of applying a reference potential to the reference solution 16. The reference potential is applied to the solution under measurement via the reference solution 16 and the porous ceramic 17, and as a result, the gate potential of the ISFET 14 becomes approximately [reference potential-potential difference of the hydrogen ion sensing film]. The metal reference electrode 15 may be, for example, an Ag / AgCl electrode, that is, an electrode in which an AgCl film is formed on an Ag surface. The metal reference electrode 15 is located on the substrate.

The reference solution 16 is filled between the porous ceramic 17 and the metal reference electrode 15, and may be, for example, an AgCl solution. The reference solution 16 together with the metal reference electrode 15 constitutes the reference electrode of the ISFET 14.

The porous ceramic 17 is filled in the third opening 23 of the second housing 19, and functions as a salt bridge that electrically connects the reference solution 16 and the solution to be measured.

The second housing 19 is coupled to the substrate 11 to seal the ISFET 14 and the metal reference electrode 15, and second and third openings 22 and 23 are formed. The second opening 22 together with the fourth opening 24 formed in the third housing 20 allows the hydrogen ion sensing film 35 of the ISFET 14 to be exposed to the solution under test. The porous ceramics 17 are filled in the third openings 23. The second housing 19 may be made of Teflon like the first housing 18. In addition, as shown in the drawing, the second housing 19 may be formed integrally with the first housing 18 or may be formed separately from the drawing.

The third housing 20 is filled between the second housing 19 and the ISFET 14, and a fourth opening 24 is formed to expose the hydrogen ion sensing layer 35 of the ISFET 14. Of course, the third housing 20 isolates the reference solution 16 from the second opening 22 so that the reference solution 16 does not leak through the second opening 22. In addition, the third housing does not expose the source electrode 36 and the drain electrode 37 of the ISFET 14. The third housing 20 may be integrally formed with the first and second housings 18 and 19 or may be separately formed. The third housing 20 may be made of, for example, polydimethylsiloxane (PDMS).

With this configuration, the reference electrode is isolated from the solution to be measured, which enables more accurate pH measurement and miniaturization.

3 is a view showing a capsule-type medical device according to an embodiment of the present invention, Figure 4 is a view showing a cross-sectional view BB 'of FIG.

3 and 4, the capsule-type medical device includes a sensor module 10 and the sensor member 10 shown in Figures 1 and 2 in combination with the outer member 40 to form a capsule. Exterior member 40 should be harmless to the human body, and should be chemically stable. The sheath member 40 may be, for example, Teflon.

The capsule medical device may further include an amplifier 51, a CPU 52, a memory 53, a transmitter 54, a battery 55, and the like. The amplifier 51 amplifies and outputs the measured value output from the sensor module 10. The CPU 52 performs a function of controlling the components located inside the capsule medical device. The memory 53 stores data necessary for the calculation of the CPU 52 or stores amplified measurement values. The transmitter 54 wirelessly transmits the amplified measurement value to the outside of the body. If the measured value is stored in the memory 53 and the measured value stored in the memory 53 is read after the capsule-type medical device is discharged from the human body, the transmitter 54 may not be included in the capsule-type medical device. have. The battery 55 supplies power to the amplifier 51, the CPU 52, the memory 53, the transmitter 54, and the sensor module 10. If power is supplied wirelessly, the capsule medical device may not require a battery 55.

The amplifier 51, the CPU 52, the memory 53, and the transmitter 54 may be formed on a separate substrate 56, and the substrates 56 may be connected to each other by a wire 57.

The sensor module and the capsule-type medical device including the same according to the present invention have an advantage that the accuracy of the measurement does not decrease even when exposed to acidic or basic digestive fluid and food.

In addition, the sensor module and the capsule-type medical device including the same according to the present invention has the advantage that it can be miniaturized.

Claims (13)

Board; A pressure sensor located on the substrate; A first housing coupled to the substrate to seal the pressure sensor, the first housing having at least one first opening configured to transmit external pressure therein; And A sensor module filled between the pressure sensor and the first housing, comprising a fluid filling to transfer the pressure delivered to the pressure sensor through the first opening to the pressure sensor. According to claim 1, The first opening has a slit shape. The method of claim 2, The sensor module has a width of the first opening is 0.5 to 2mm. According to claim 1, The filler is an insulating oil sensor module. According to claim 1, The first housing is a sensor module made of Teflon. According to claim 1, An ISFET positioned on the substrate and including a source, a drain, a channel, an insulating film, and a hydrogen ion sensing film; A metal reference electrode on the substrate; A second housing coupled to the substrate to seal the ISFET and the metal reference electrode, the second housing having second and third openings formed therein; A third housing filled between the second housing and the ISFET, the third housing having a fourth opening for exposing the hydrogen ion sensing film together with the second opening; A porous ceramic filled in the third opening; And The sensor module further comprises a reference solution filled between the porous ceramic and the reference electrode. The method of claim 6, The hydrogen ion sensing film is located on the insulating film, The hydrogen ion sensing membrane is made of Ta ₂ O ₅ , SiO ₂ , Si ₃ N ₄ , PtO ₂ , IrO ₂ , RuO ₂ , Al ₂ O ₃ or ZrO ₂ , The metal reference electrode is made of Ag / AgCl, The reference solution is a sensor module AgCl solution. The method of claim 6, The second housing is integrally formed with the first housing, The third housing is a sensor module made of PDMS. Board; An ISFET positioned on the substrate and including a source, a drain, a channel, an insulating film, and a hydrogen ion sensing film; A metal reference electrode on the substrate; A first housing coupled to the substrate to seal the ISFET and the metal reference electrode and having first and second openings formed therein; A second housing filled between the first housing and the ISFET, the second housing having a third opening to expose the hydrogen ion sensing film together with the first opening; A porous ceramic filled in the second opening; And A sensor module comprising a reference solution filled between the porous ceramic and the metal reference electrode. The method of claim 9, The hydrogen ion sensing film is located on the insulating film, The hydrogen ion sensing membrane is made of Ta ₂ O ₅ , SiO ₂ , Si ₃ N ₄ , PtO ₂ , IrO ₂ , RuO ₂ , Al ₂ O ₃ or ZrO ₂ , The reference electrode is made of Ag / AgCl, The reference solution is a sensor module AgCl solution. The method of claim 9, The first housing is made of Teflon, The second housing is a sensor module made of PDMS. In the capsule-type medical device comprising a sensor module and an outer member in combination with the sensor module to form a capsule, The sensor module is a capsule type medical device according to any one of claims 1 to 11. The method of claim 12, An amplifier for amplifying and outputting the measured value measured by the sensor module; At least one of a memory for storing the measured value output from the amplifier and a transmitter for wirelessly transmitting the measured value output from the amplifier; And And a battery for supplying power to at least one of the memory and the transmitter, the amplifier and the sensor module.

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