阅读说明：本技术 环烯烃聚合物与金属的接合方法、生物感测器的制造方法、及生物感测器 (Method for bonding cycloolefin polymer and metal, method for manufacturing biosensor, and biosensor ) 是由 舩桥理佐 桥本泰知 寺井弘和 三宅史夏 于 2018-12-10 设计创作，主要内容包括：本发明提供一种将第1构件(覆盖板)与第2构件(电极板)接合的方法,上述第1构件(覆盖板)具有由环烯烃聚合物形成的第1被接合面,上述第2构件(电极板)具有由金属形成的第2被接合面,且具备以下步骤：将第1被接合面及第2被接合面暴露于H<Sub>2</Sub>O电浆及O<Sub>2</Sub>电浆中的至少一者(步骤S21)；及合并第1被接合面与第2被接合面(步骤S22)。(The present invention provides a method for joining a 1 st member (cover plate) and a 2 nd member (electrode plate), wherein the 1 st member (cover plate) has a 1 st joined surface formed of a cycloolefin polymer, the 2 nd member (electrode plate) has a 2 nd joined surface formed of a metal, and the method includes the steps of: exposing the 1 st bonded surface and the 2 nd bonded surface to H 2 O plasma and O 2 At least one of the plasmas (step S21); and combining the 1 st bonded surface and the 2 nd bonded surface (step S22).)

1. A method for joining a 1 st member and a 2 nd member, wherein the 1 st member has a 1 st joined surface made of a cycloolefin polymer, and the 2 nd member has a 2 nd joined surface made of a metal, the method comprising the steps of:

exposing the 1 st bonded surface and the 2 nd bonded surface to H₂O plasma and O₂At least one of the plasmas; and

the 1 st bonded surface and the 2 nd bonded surface are combined.

2. The joining method according to claim 1, wherein after the step of combining the 1 st surface to be joined and the 2 nd surface to be joined,

the method includes the step of applying pressure and heat to the joined surfaces.

3. A method for manufacturing a biosensor, comprising the steps of:

preparing a cover plate having a 1 st bonded surface formed of a cycloolefin polymer and having a recess, and an electrode plate having a 2 nd bonded surface formed with a metal film to be an electrode;

exposing the 1 st bonded surface and the 2 nd bonded surface to H₂O plasma and O₂At least one of the plasmas; and

the 1 st bonded surface and the 2 nd bonded surface are combined.

4. The method of claim 3, wherein after the step of combining the 1 st bonded surface and the 2 nd bonded surface,

the method includes the step of applying pressure and heat to the joined surfaces.

5. A biosensor, comprising:

a cover plate formed of a cycloolefin polymer and having a recess formed on one main surface; and

and an electrode plate having a metal film serving as an electrode formed on one main surface thereof, the one main surface being directly bonded to the main surface of the cover plate on the side where the recess is formed.

6. The biosensor of claim 5,

the metal film to be an electrode is formed of Ru, Ni-W, Au, Ag, Al, or Cu.

7. The biosensor of claim 6,

the metal film serving as the electrode is formed by applying or printing a nano paste, which is a nano ink obtained by dispersing fine particles of the metal in a solvent, on a substrate.

Technical Field

The present invention relates to a technique for bonding a cycloolefin polymer (COP) to a metal.

Background

In recent years, in a medical field or the like, a measuring apparatus called a biosensor has been used for measuring the content of a specific biological substance (for example, blood glucose level) in a biological sample such as blood. The biosensor measures the content of a specific biological substance in a biological sample by using a sharp reaction between the specific biological substance and a specific chemical substance (reactant substance), such as an enzymatic reaction or an antigen-antibody reaction.

For example, a biosensor described in patent document 1 includes an electrode plate in which a plurality of linear electrodes made of a metal thin film are formed on a main surface of a long flat plate-shaped base material made of an insulating material. Each electrode extends along the longitudinal direction of the electrode plate, and a reaction substance corresponding to a biological substance to be detected is disposed at a specific position in the course of the extension.

A double-sided tape as a separator is bonded to a main surface of the electrode plate on the side where the electrodes are arranged so as to cover substantially the entire surface except for the vicinity of one end portion thereof, and a cover plate is bonded to the other adhesive surface of the double-sided tape. That is, the double-sided tape and the cover plate are disposed so that one end portion of the main surface of the electrode plate (i.e., the end portion of the electrode) is exposed and the other portion is entirely covered. The electrode portion exposed from the cover plate or the like forms a terminal portion to which a voltage is applied from the outside.

The separator provided between the electrode plate and the cover plate is cut off at a point in the longitudinal direction of the electrode plate, and at the cut-off portion, an elongated space (i.e., an elongated space extending in the short-side direction of the electrode plate) exposed to the electrode and the reactant is formed between the electrode plate and the cover plate. The space forms a sample holding space for holding a biological sample.

In the case of measuring the content of a biological substance contained in a biological sample using the biosensor, first, the biological sample (typically, blood) is introduced into a sample-holding space. Then, the specific biological substance contained in the biological sample reacts with the reaction substance to produce the specific substance. At this time, when a specific voltage is applied to the electrode portion (terminal portion) exposed from the end of the biosensor, a current corresponding to the amount of the substance generated by the reaction flows between the electrodes. By measuring the amount of current, the amount of the substance, and further the amount of the biological substance contained in the biological sample (for example, the glucose concentration in blood) can be measured.

Disclosure of Invention

Problems to be solved by the invention

In the biosensor, accurate measurement is required with a small amount of a biological sample. In order to bring the minimum necessary biological sample into contact with the electrodes and the reaction substance and reduce the amount of the remaining biological sample not in contact with these, it is preferable to reduce the size of the sample holding space in the thickness direction of the biosensor.

However, in the biosensor described in patent document 1, the size of the sample holding space in the thickness direction of the biosensor cannot be made smaller than the thickness of the double-sided tape serving as a spacer.

In general, biosensors are discarded after being used up in one measurement, and therefore it is necessary to suppress the manufacturing cost as much as possible. However, in the biosensor described in patent document 1, in which a pair of plates are integrated with a double-sided tape interposed therebetween, the number of parts and the number of manufacturing steps are large, and it is difficult to sufficiently suppress the manufacturing cost.

To avoid these problems, for example, it is conceivable to form a groove in advance in a cover plate, directly join the cover plate to an electrode plate, and form a sample holding space by the groove. In this case, the depth of the groove is sufficiently small, whereby the size of the sample holding space in the thickness direction of the biosensor can be sufficiently small. Further, when the electrode plate and the cover plate are directly joined, the number of parts and the number of manufacturing steps are reduced as compared with the case of using the spacer, and the manufacturing cost can be suppressed.

However, a cycloolefin polymer (COP) that is preferably used as a material for forming the cover plate in recent years is a hydrophobic resin, and thus has low adhesion to other members. Therefore, it has not been possible in the prior art to directly bond a cover plate made of COP to an electrode plate having a metal film formed thereon.

The present invention has been made to solve the above-described problems, and an object thereof is to provide a technique capable of directly bonding a surface to be bonded made of COP and a surface to be bonded made of metal.

Means for solving the problems

The present invention has been made to solve the above problems:

a method for joining a 1 st member and a 2 nd member, wherein the 1 st member has a 1 st joined surface formed of a cycloolefin polymer (COP), and the 2 nd member has a 2 nd joined surface formed of a metal, the method comprising the steps of:

exposing the 1 st bonded surface and the 2 nd bonded surface to H₂O plasma and O₂At least one of the plasmas; and

the 1 st bonded surface and the 2 nd bonded surface are combined.

According to this method, the 1 st bonded surface made of COP and the 2 nd bonded surface made of metal can be directly bonded. The reason is considered as follows. First, by exposure to H₂O plasma and O₂At least one of the plasmas is used to modify a hydrophilic functional group (hydroxyl or carboxyl) on the 1 st bonded surface formed by COP. And, by exposure to H₂O electricitySlurry and O₂At least one of the plasmas, and a 2 nd bonded surface formed of a metal is also provided with a hydrophilic functional group. By combining these bonded surfaces, a dehydration reaction occurs between the functional groups of both bonded surfaces, and a covalent bond is formed between both functional groups. Thereby, the two bonded surfaces are directly bonded.

In the above-described present invention,

after the step of combining the 1 st bonded surface and the 2 nd bonded surface,

a step of applying pressure and heat to the joined surfaces is added.

In the above method, examples of the metal forming the 2 nd bonded surface include: ru (ruthenium), Ni-W (nickel-tungsten), Au (gold), Al (aluminum), Cu (copper), etc. The metal may be formed by applying or printing a nano ink (nano paste) in which fine particles of the metal are dispersed in a solvent on a substrate.

Yet, another aspect of the present invention is:

a method for manufacturing a biosensor, comprising the steps of:

preparing a cover plate having a 1 st bonded surface formed of a cycloolefin polymer (COP) and having a recess, and an electrode plate having a 2 nd bonded surface formed with a metal film to be an electrode;

exposing the 1 st bonded surface and the 2 nd bonded surface to H₂O plasma and O₂At least one of the plasmas; and

the 1 st bonded surface and the 2 nd bonded surface are combined.

According to this method, the 1 st bonded surface formed of COP and the 2 nd bonded surface formed with the metal film to be an electrode are directly bonded, and the cover plate and the electrode plate can be integrated. Therefore, a member such as a double-sided tape for integrating both plates is not required, and the manufacturing cost of the biosensor can be suppressed. In the biosensor, the size of the sample holding space in the thickness direction of the biosensor can be made arbitrary by adjusting the depth of the recess formed in the cover plate.

In particular, in this method, the 1 st bonded surface is used as H₂O plasma and O₂At least one of the plasmas is treated to hydrophilize the recess formed therein (i.e., the recess forming the sample-holding space). Therefore, the sample can be easily flowed into the sample holding space. This enables rapid and accurate measurement with a small amount of sample.

In the method, the first step of the method,

also, after the step of combining the 1 st bonded surface and the 2 nd bonded surface,

a step of applying pressure and heat to the joined surfaces is added.

Yet, another aspect of the present invention is:

a biosensor, comprising:

a cover plate formed of a cycloolefin polymer (COP) and having a recess formed on one main surface; and

and an electrode plate having a metal film serving as an electrode formed on one main surface thereof, the one main surface being directly bonded to the main surface of the cover plate on the side where the recess is formed.

According to this biosensor, since the cover plate is directly bonded to the electrode plate, a member such as a double-sided tape for integrating both plates is not required, and the biosensor can be manufactured at low cost. Further, by adjusting the depth of the recess formed in the cover plate, the size of the sample holding space in the thickness direction of the biosensor can be set to any size.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the surface to be bonded made of COP and the surface to be bonded made of metal can be directly bonded.

Drawings

FIG. 1 is a diagram for explaining a configuration of a biosensor and an example of use thereof.

FIG. 2 is a schematic configuration diagram of a plasma processing apparatus.

Fig. 3A is a diagram showing a flow of the 1 st process of manufacturing a biosensor.

Fig. 3B is a diagram showing a flow of the 2 nd process of manufacturing the biosensor.

FIG. 4 is a graph showing the conditions of the plasma treatment in examples 1 and 2 and reference examples 1 to 3.

FIG. 5 is a table summarizing evaluation of the bonding results in examples 1 and 2 and reference examples 1 to 3.

FIG. 6 is a graph showing the conditions of the plasma treatment in examples 3 and 4.

FIG. 7 is a diagram for explaining the processing conditions in examples 3 and 4.

FIG. 8 is a table summarizing the results of examples 3 and 4 and comparative examples 1 to 3 as to whether or not the sheets are engageable.

Fig. 9 is a table summarizing the measurement results of the contact angle of pure water after the plasma treatment.

Fig. 10 is a table summarizing the engageability table in the case where the temperature and pressure conditions are different.

Detailed Description

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

<1. biosensor >

<1-1. construction of biosensor >

The structure of the biosensor according to the present invention will be described with reference to FIG. 1. FIG. 1 is a diagram for explaining the structure of a biosensor 8 and an example of its use.

The biosensor 8 includes a cover plate 81 and an electrode plate 82 directly bonded thereto.

The cover plate 81 is a long rectangular flat plate-like plate and is formed of a cycloolefin polymer (COP). On one main surface 810 of the cover plate 81, grooves (recesses) 811 are formed, the grooves (recesses) 811 extending in the short-side direction of the cover plate 81 and having both ends open to both side surfaces of the cover plate 81.

The electrode plate 82 includes a bottom plate 821 serving as a base material. The bottom plate 821 is a flat rectangular member having substantially the same shape as the cover plate 81 except that the length in the longitudinal direction is slightly longer than the cover plate 81, and is formed of an insulating material (for example, polyethylene terephthalate (PET), glass, COP, or the like).

A plurality of (2 in the drawing) line-shaped electrodes 822, 822 made of a metal thin film are formed on one main surface of the base 821. Each electrode 822 extends in the entire longitudinal direction of the bottom plate 821. As a metal to be used for each electrode 822, typically, Ru (ruthenium), Ni — W (nickel-tungsten), Au (gold), Ag (silver), Al (aluminum), Cu (copper), or the like is assumed. However, metals other than these metals may be used as the electrode 822. Each electrode 822 may be formed by applying or printing a nano ink (nano paste) in which fine particles of the metal are dispersed in a solvent to the base 821.

At a specific position (a portion corresponding to the concave portion 811) in the middle of the extension of the electrode 822, a reaction substance 823 corresponding to a biological substance to be measured is disposed.

The biosensor 8 is formed by directly bonding the main surface 810 on the side where the recess 811 is formed in the cover plate 81 and the main surface 820 on the side where the electrodes 822, 822 are arranged in the electrode plate 82 (an example of bonding the two plates 81, 82 will be described later).

As described above, the length of the cover plate 81 in the longitudinal direction is slightly shorter than the electrode plate 82. Therefore, in a state where the plates 81 and 82 are joined, the cover plate 81 exposes one end portion of the main surface 820 of the electrode plate 82 (i.e., the end portion of each electrode 822) and covers the other portions entirely. The end portion of each electrode 822 exposed from the cover plate 81 forms a terminal portion 801 to which a voltage is applied from the outside.

In the joined state of the plates 81 and 82, a part of the cover plate 81 where the recess 811 is formed forms an elongated space (i.e., an elongated space extending in the short-side direction of the biosensor 8) between the plates 81 and 82, which is exposed to the electrodes 822 and the reaction material 823. The space forms a sample holding space 802 for holding a biological sample.

<1-2. use example of biosensor >

Next, an example of use of the biosensor 8 will be described with reference to fig. 1.

First, the terminal portion 801 of the biosensor 8 is inserted from the opening 91 of the external device 9. Then, in this state, a biological sample (for example, blood) is caused to flow into the sample holding space 802 of the biosensor 8. Then, the specific biological substance contained in the biological sample reacts with the reaction substance 823 to generate the specific substance.

The external device 9 applies a specific voltage to the terminal portion 801 of the biosensor 8 (specifically, between the electrodes 822, 822), and measures the amount of current flowing between the electrodes 822, 822 at that time. Based on the measured current amount, the amount of the substance produced by the reaction (and thus the amount of the biological substance contained in the biological sample) is measured.

<2. example of bonding >

<2-1 > plasma treatment apparatus >

Next, a method of manufacturing the biosensor 8 will be described. Before specifically describing this method, the structure of the plasma processing apparatus used in this method will be described with reference to fig. 2. Fig. 2 is a diagram schematically showing the configuration of the plasma processing apparatus 100.

The plasma processing apparatus 100 (product name: AQ-2000, manufactured by SAMCO corporation) is a parallel plate type (capacitive coupling type) plasma processing apparatus, and includes: a process chamber 1 forming a process space therein; a gas supply unit 2 for supplying a gas into the processing chamber 1; and a pair of electrodes 3 and 4 disposed to face each other in the vertical direction in the processing chamber 1. The plasma processing apparatus 100 further includes a control unit 5 for controlling each of the elements included therein.

The processing chamber 1 is provided with a gas inlet 11 for introducing gas into the processing chamber 1 and an exhaust port 12 for exhausting gas from the processing chamber 1. The gas inlet 11 is connected to the gas supply unit 2. A pipe 123 is connected to the exhaust port 12, and a valve 121 and a vacuum pump 122 are inserted into the pipe 123. The processing chamber 1 is provided with a load port (not shown) for loading the object to be processed therein and a load lock chamber (not shown) for closing the load port.

The gas supply unit 2 includes a water supply source 21 for supplying water and an oxygen supply source 22 for supplying oxygen. The supply sources 21 and 22 are connected to the gas inlet 11 via pipes 210 and 220. A vaporizer (vaporizing device) 211 for vaporizing water into water vapor, a mass flow controller 212, and a valve 213 are inserted into a pipe 210 connected to the water supply source 21. On the other hand, a mass flow controller 221 and a valve 222 are inserted into a pipe 220 connected to the oxygen gas supply source 22.

An upper surface of a lower electrode (lower electrode) 3 of a pair of electrodes 3 and 4 disposed to face each other in the vertical direction in the processing chamber 1 serves as a mounting surface on which an object to be processed is mounted. An electrostatic chuck or the like (not shown) for fixing the object to be processed is provided on the upper surface. The lower electrode 3 is grounded. On the other hand, a high-frequency power supply 42 is connected to the upper electrode (upper electrode) 4 via a capacitor 41.

The control unit 5 implements various functional elements by using a personal computer or the like as a hardware resource and executing dedicated control and processing software installed in the personal computer. The control unit 5 is connected to a display unit including a liquid crystal display or the like and an input unit (not shown) including a mouse, a keyboard, a touch panel, and the like.

The control unit 5 is electrically connected to the vaporizing device 211, the mass flow controllers 212 and 221, and the valves 213 and 222, and controls the type of gas introduced into the processing chamber 1, the flow rate of the gas, and the timing of introduction and stop of the gas. The control unit 5 is electrically connected to the valve 121 and the pump 122, and controls the timing of discharging and stopping the gas from the inside of the processing chamber 1. The control unit 5 is electrically connected to the high-frequency power supply 42, and controls the time point, power value, and the like of the high-frequency power input to the upper electrode 4.

<2-2. flow of treatment >

A method of manufacturing the biosensor 8 will be described with reference to fig. 3A. Fig. 3A is a diagram showing a flow of a process of manufacturing the biosensor 8.

Step S1: first, the cover plate 81 and the electrode plate 82 are prepared. The specific structure of each plate 81, 82 is as described above.

Step S2: next, the main surface 810 on the side where the recess 811 is formed in the cover plate 81 is joined to the main surface 820 on the side where the electrode 822 is formed in the electrode plate 82. The processing of step S2 will be specifically described below. In the following description, the main surface 810 of the cover plate 81 on the side of joining to the electrode plate 82 is referred to as "1 st joined surface 810", and the main surface 820 of the electrode plate 82 on the side of joining to the cover plate 81 is referred to as "2 nd joined surface 820".

Step S21: first, the 1 st bonded surface 810 of the cover plate 81 and the 2 nd bonded surface 820 of the electrode plate 82 are bonded by using H₂O plasma or O₂The plasma is used for processing. The processing is performed using, for example, the plasma processing apparatus 100 described above.

In this case, first, the cover plate 81 and the electrode plate 82 are carried into the processing chamber 1 through a carrying-in port not shown, and the plates 81 and 82 are placed on the lower electrode 3 in a posture in which the bonded surfaces 810 and 820 of each are directed upward, and fixed by the electrostatic chuck.

Then, H is formed inside the processing chamber 1₂O plasma or O₂Plasma is generated. Specifically, after the transfer port is closed to form a closed space inside the processing chamber 1, the gas supply unit 2 starts to introduce water vapor or oxygen gas into the inside. At the same time, the inside is exhausted to maintain a specific pressure. Here, the pressure in the processing chamber 1 in the plasma processing is preferably maintained below the atmospheric pressure. In particular, if the pressure in the plasma treatment reaches above atmospheric pressure, H₂The temperature at the time of O plasma generation is 100 ℃ or higher, and thus the 1 st bonded surface made of a cycloolefin polymer tends to be deformed or deteriorated. Therefore, the pressure in the plasma treatment is more preferably maintained in the range of 0.1Pa to 2000 Pa.

Then, high-frequency power is input from the high-frequency power supply 42 to the upper electrode 4. Then, the gas introduced into the processing chamber 1 is made into a plasma state to generate plasma. Of course, when the water vapor is introduced into the processing chamber 1, H is generated in the processing chamber 1₂O plasma (water plasma) generated when oxygen gas is introduced into the processing chamber 1₂Plasma (oxygen plasma). By placing on the lower electrode 3The bonded surfaces 810 and 820 of the plates 81 and 82 are exposed to the plasma generated in the processing chamber 1, and the plasma processing of the bonded surfaces 810 and 820 is performed.

After a predetermined processing time has elapsed after the plasma processing is started, the gas supply unit 2 stops the introduction of the water vapor or the oxygen gas into the processing chamber 1 and stops the supply of the high-frequency power from the high-frequency power supply 42 to the upper electrode 4, thereby ending the plasma processing. Thereafter, the inside of the processing chamber 1 is returned to the atmospheric pressure, and the plates 81 and 82 are carried out from the processing chamber 1.

Step S22: then, the bonded surfaces 810 and 820 of the two plates 81 and 82 subjected to the plasma treatment are combined.

The both surfaces to be bonded 810 and 820 are directly bonded by the processing of step S21 to step S22. The reason is considered as follows. First, a hydrophilic functional group (hydroxyl group or carboxyl group) is modified on the 1 st surface to be bonded 810 by the plasma treatment in step S21. Furthermore, a hydrophilic functional group is also provided to the 2 nd bonded surface 820. When the two bonded surfaces 810 and 820 subjected to the overplating treatment are brought together in step S22, the distance between the functional groups of the bonded surfaces 810 and 820 is close to a distance at which hydrogen bonds can be formed. As a result, a dehydration reaction occurs between the functional groups of the bonded surfaces 810 and 820, and a covalent bond is formed between the functional groups. Thereby, the two engaged surfaces 810 and 820 are directly engaged.

The biosensor 8 is obtained by directly bonding the 1 st bonded surface 810 of the cover plate 81 and the 2 nd bonded surface 820 of the electrode plate 82.

After the process of step S22, the pressure and heat may be applied to both the bonded surfaces 810 and 820. In this case, the process flow of manufacturing the biosensor 8 is as shown in FIG. 3B. That is, the flow in this case is such that step S2 in fig. 3A becomes step S2B, and step S2B becomes the result of adding step S23 after step S22. Next, step S23 will be explained.

Step S23: after step S22, pressure and heat are applied to the combined bonded surfaces 810 and 820. That is, both the surfaces to be bonded 810 and 820 are pressurized and heated. Specifically, this step is performed as follows using a pair of heaters 71a and 71b and a pair of metal blocks 72a and 72b, for example, as illustrated in fig. 5 (b). That is, the object (here, the pair of plates 81 and 82 on which the bonded surfaces 810 and 820 are joined) is placed on the metal block 72a placed on the single heater 71 a. Then, another heater 71b and another metal block 72b are sequentially placed thereon. Then, the pressing member 73 presses the upper metal block 72b toward the lower metal block 72a, thereby pressing the object sandwiched therebetween. The pair of heaters 71a and 71b are adjusted to a specific temperature, thereby heating the object held therebetween.

At this time, the pressure applied to the two bonded surfaces 810 and 820 can be set to 400 (N/cm), for example²) Above and 2400 (N/cm)²) The following. For example, the pressure is set to 1600 (N/cm)²) In the case of (3), the heating temperature of both the bonded surfaces 810 and 820 may be 90 ℃ to 150 ℃, and is preferably 95 ℃ to 150 ℃. The time for heating and pressurizing may be set to 5 minutes, for example.

The two bonded surfaces 810 and 820 are also directly bonded by the processing of step S21 to step S23. The reason is considered as follows. First, a hydrophilic functional group (hydroxyl group or carboxyl group) is modified on the 1 st surface to be bonded 810 by the plasma treatment in step S21. Furthermore, a hydrophilic functional group is also provided to the 2 nd bonded surface 820. When the two bonded surfaces 810 and 820 subjected to the overplating treatment are brought into a combined state in step S22 and pressure is applied in step S23, the distance between the functional groups of the bonded surfaces 810 and 820 is close to a distance at which hydrogen bonds can be formed. By further applying heat thereto, a dehydration reaction occurs between the functional groups of the two bonded surfaces 810 and 820, thereby forming a covalent bond between the two functional groups. Thereby, the two engaged surfaces 810 and 820 are directly engaged.

The biosensor 8 is obtained by directly bonding the 1 st bonded surface 810 of the cover plate 81 and the 2 nd bonded surface 820 of the electrode plate 82.

<3. example >

< example 1>

COP samples (size: 15mm × 10mm,0.5mm in thickness (product name: ZEONOR1060R, manufactured by ZEON, Japan), and a metal specimen (size: 15mm × 10mm, average roughness Ra of gold thin film portion: 1.332nm) in which a gold thin film was formed on the surface of a titanium wafer by sputtering₂The O plasma treats one main surface of the COP sample and a main surface of the metal sample on the side where the metal film is formed. As shown in FIG. 4, the high-frequency power was set to 100W, the flow rate of the water vapor was set to 20sccm, the pressure in the processing chamber was set to 5Pa, and the processing time was set to 80 seconds. The processing mode of the plasma processing apparatus is set to PE mode.

Second, warp H in the metal samples was combined₂O plasma treated principal surface and H in COP sample₂Specifically, the main surface of the metal sample and the main surface of the COP sample were combined so as to overlap a square region of 10mm × 10 mm.

Next, the strength of the 3-time bonding surface was measured by simultaneously stretching the other main surface of the metal sample and the other main surface of the COP sample by a tensile tester, and the average value thereof was obtained.

< reference example 1>

The bonding samples prepared in example 1 were pressurized at room temperature (24 ℃) and the average bonding strength was determined in the same manner as in example 1. The bonding sample is pressurized by placing the bonding sample on a 1 st block made of metal, placing a 2 nd block made of metal on the bonding sample, and pressurizing an upper surface of the 2 nd block by a hydraulic cylinder. The pressure was set to 4900 (N/cm)²) This was done for 10 minutes.

< example 2>

An average value of the joining strength was determined in the same manner as in example 1, except that a COP sample (size: 15mm 8510 mm, thickness: 50 μm) (manufactured by ZEON, product name: ZEONOrZF14-050, Japan) was used.

< reference example 2>

The average value of the bonding strength was determined in the same manner as in reference example 1, except that a COP sample (size: 15mm × mm, thickness: 50 μm) (manufactured by ZEON, product name: ZEONORZF14-050) and a metal sample in which an aluminum thin film (thickness of thin film: 300nm, average roughness Ra of aluminum thin film portion: 5.462nm) was formed on the surface of a silicon wafer by an evaporation method were used.

< reference example 3>

The average value of the bonding strength was determined in the same manner as in reference example 2, except that a metal sample was used in which a copper thin film (the thickness of the thin film: 1 μm, the average roughness Ra of the copper thin film portion: 3.032nm) was formed on the surface of a silicon wafer by a vapor deposition method.

Fig. 5 shows the evaluation of the bonding results in examples 1 and 2 and reference examples 1 to 3, which were prepared in the above manner. It can be confirmed that: in examples 1 and 2 in which no pressurization was performed, the bonding was sufficient.

< example 3>

As the COP sample 61, 3 rectangular COP films (size: 10mm 3520 mm, thickness: 0.5mm) were prepared, and 3 kinds of metal samples (1 st metal sample 62a, 2 nd metal sample 62b, and 3 rd metal sample 62c) were prepared, the 1 st metal sample 62a was obtained by integrally forming a Ru (ruthenium) film on one main surface of a film (size: 10mm × mm) formed of PET, the 2 nd metal sample 62b was obtained by integrally forming a Ni-W (nickel-tungsten) film on one main surface of a film (size: 10mm × mm) formed of PET, and the 3 rd metal sample 62c was obtained by integrally forming an Au (gold) film on one main surface of a film (size: 10mm × mm) formed of PET.

By means of H₂The O plasma was applied to one main surface of the 3 COP samples 61 and the main surface of the 3 metal samples 62a, 62b, and 62c on the side where the metal film was formed. As shown in fig. 6, the high-frequency power was set to 100W, the flow rate of the water vapor was set to 20sccm, the pressure in the processing chamber was set to 5Pa, and the processing time was set to 40 seconds. Further, as the plasma treatment apparatus, a plasma treatment apparatus (product name: AQ-2000) manufactured by SAMCO was used (the treatment mode was PE mode).

Next, the samples 62a of metal 1 were combined with H₂Main surface on the back side of O plasma treatment and H in COP sample 61₂O plasma treating the rear main surface. Specifically, as shown in FIG. 7(a), of the 1 st metal sample 62aThis main face merges with the main face of the COP sample 61 in such a way as to overlap a square region of 10mm × 10mm for the 2 nd metal sample 62b and the 3 rd metal sample 62c, also in the same way will be H₂H in the main surface on the O plasma treatment rear side and COP sample 61₂The main surfaces on the back side of the O plasma treatment are merged.

Next, the sample pairs in which the main surfaces of the COP sample 61 and the metal samples 62a, 62b, and 62c were combined (each of the 1 st sample pair 60a in which the 1 st metal sample 62a and the COP sample 61 were combined, the 2 nd sample pair 60b in which the 2 nd metal sample 62b and the COP sample 61 were combined, and the 3 rd sample pair 60c in which the 3 rd metal sample 62c and the COP sample 61 were combined) were pressurized and heated.

Specifically, each sample pair 60a, 60b, 60c was SiO₂The thin plate was sandwiched, and heated and pressed by using the apparatus shown in fig. 7 (b). I.e. will be in SiO₂Each sample pair 60a, 60b, and 60c held by the thin plates is placed on the 1 st metal block 72a (the 1 st metal block 72a placed on the 1 st heater 71 a), and the 2 nd heater 71b and the 2 nd metal block 72b are sequentially placed thereon. The 2 nd metal block 72b is provided to be able to ascend and descend along a pair of guide posts 74, 74 provided upright on the 1 st metal block 72a, and is pressed toward the 1 st metal block 72a with a certain load by a pair of pressing members 73, 73. Each pressing member 73 is formed, for example, by a screw member that penetrates the 2 nd metal block 72b from the upper side and is screwed at the lower end to a screw hole provided in the 1 st metal block 72 a. In this case, the magnitude of the pressure applied to the sample pairs 60a, 60b, 60c can be adjusted by the torque applied to the upper end of each pressing member 73. Here, the temperature of the heaters 71a and 71b was set to 100 ℃ and the pressure applied to the sample pairs 60a, 60b and 60c was set to 1600 (N/cm)²). The time for heating and pressurizing was set to 5 minutes.

In 3 sets of sample pairs 60a, 60b, and 60c subjected to the series of treatments in example 3, whether or not the COP sample 61 and the metal samples 62a, 62b, and 62c were joined was visually confirmed. As a result, as shown in the table of fig. 8, it was confirmed that: in all of the 1 st sample pair 60a, the 2 nd sample pair 60b, and the 3 rd sample pair 60c, the COP sample 61 and the metal samples 62a, 62b, and 62c were bonded.

As described above, the reason why the COP sample 61 and the metal samples 62a, 62b, and 62c are bonded to each other is considered to be that a hydrophilic functional group is formed on the surfaces to be bonded of the samples 61, 62a, 62b, and 62c by plasma treatment, and a covalent bond is formed between the functional groups of the surfaces to be bonded by heating and pressing. To verify this, H was performed under the above-mentioned treatment conditions₂The contact angle of pure water on the surfaces to be bonded of each of the samples 61, 62a, 62b, and 62c after the O plasma treatment was measured, and the measurement results shown in fig. 9 were obtained. Thus, it is known that the compound represented by the formula H₂The O plasma treatment hydrophilizes the surfaces to be bonded of the samples 61, 62a, 62b, and 62c (generates hydrophilic functional groups on the surfaces to be bonded).

< example 4>

By using O₂The same samples 61, 62a, 62b, and 62c as in example 3 were treated with plasma, and a part of the main surface of each sample was combined as 3 sets of sample pairs 60a, 60b, and 60c in the same manner as described above, and they were pressurized and heated. The plasma treatment conditions were the same as those in example 3 except that the type of gas was changed from water vapor to oxygen (fig. 6). The conditions for heating and pressurizing were the same as in example 3.

In 3 sets of sample pairs 60a, 60b, and 60c subjected to the series of treatments in example 4, whether or not the COP sample 61 and the metal samples 62a, 62b, and 62c were joined was visually confirmed. As a result, as shown in the table of fig. 8, it was confirmed that: in all of the 1 st sample pair 60a, the 2 nd sample pair 60b, and the 3 rd sample pair 60c, the COP sample 61 and the metal samples 62a, 62b, and 62c were bonded.

Here, O is also carried out under the above-mentioned treatment conditions₂The contact angle of pure water was measured for each of the samples 61, 62a, 62b, and 62c after the plasma treatment, and the measurement results shown in fig. 9 were obtained. Thus, it is known that O is added₂The plasma treatment hydrophilizes the surfaces to be bonded of the samples 61, 62a, 62b, and 62c (generates hydrophilic functional groups on the surfaces to be bonded).

< comparative experiment 1>

Comparative example 1: in example 3, H was not performed₂And (4) performing O plasma treatment. That is, samples 61, 62a, 62b, and 62c similar to those of example 3 were not subjected to any plasma treatment, and a part of the main surface was combined as 3 sets of sample pairs 60a, 60b, and 60c in the same manner as described above, and they were pressurized and heated. The conditions of pressurization and heating were the same as in example 3.

Comparative example 2: in example 3, heating and pressurization were not performed. That is, samples 61, 62a, 62b, and 62c, which were the same as in example 3, were each replaced with H₂The O plasma treatment was performed to combine a part of the main surfaces as 3 sets of sample pairs 60a, 60b, 60c without heating and pressurizing in the same manner as described above. The conditions of the plasma treatment were the same as those in example 3.

Comparative example 3: in example 4, heating and pressurization were not performed. That is, samples 61, 62a, 62b, and 62c, which were the same as in example 4, were treated with O₂The plasma treatment was carried out in the same manner as described above, and a part of the main surface was combined as 3 sets of sample pairs 60a, 60b, and 60c without heating and pressurizing. The conditions of the plasma treatment were the same as those in example 4.

In 3 sets of sample pairs 60a, 60b, and 60c of comparative examples 1 to 3, which were subjected to each treatment, whether or not the COP sample 61 and the metal samples 62a, 62b, and 62c were joined was visually confirmed. As a result, as shown in the table of fig. 8, in any of comparative examples 1 to 3, the COP sample 61 and the metal samples 62a, 62b, and 62c were not bonded.

< comparative experiment 2>

A plurality of COP samples 61 (rectangular COP film sheet (size: 10mm 8520 mm, thickness: 0.5mm)) similar to example 3 and a 1 st metal sample 62a (obtained by integrally forming a Ru thin film on one main surface of a film sheet (size: 10mm × mm) formed of PET) similar to example 3 were prepared, and the COP samples were passed through a passage H₂The O plasma treats one main surface of each COP sample 61 and the main surface of each 1 st metal sample 62a on the side where the metal film is formed. The processing conditions of the plasma treatment were the same as those in example 3. Then, in the same manner as in example 3, H in each of the 1 st metal samples 62a was combined₂H in the main surface on the back side of the O plasma treatment and each COP sample 61₂After O plasma treatmentThe side main surface (see fig. 5 (a)). Then, each sample pair (1 st sample pair 60a) in which the main surfaces of the 1 st metal sample 62a and the COP sample 61 were combined was pressurized and heated by the same method as in example 3 (see fig. 5 (b)). Here, each of the plurality of sample pairs 60a is heated and pressurized under different temperature and pressure conditions by adjusting the temperature of the pair of heaters 71a and 71b and the torque applied to the upper end of each of the pressing members 73. The heating and pressurizing time was set to 5 minutes.

In each sample pair 60a subjected to heating and pressing under different temperature and pressure conditions, whether or not the COP sample 61 and the 1 st metal sample 62a were bonded was visually confirmed. Fig. 10 shows the results. As shown here, for example, at an additional pressure of 400 (N/cm)²) In the case of (1), the joining is carried out by heating at 100 ℃ or higher, and the applied pressure is 2400 (N/cm)²) In the case of (3), the joining is carried out by heating at 85 ℃ or higher. That is, it is known that the higher the additional pressure is, the lower the heating temperature is to achieve bonding (from another viewpoint, the higher the heating temperature is, the lower the pressure is to achieve bonding).

Also, for example, at an additional pressure of 1600 (N/cm)²) In the case of (3), the joining is carried out by heating at 90 ℃ or higher. However, in this case, when the heating temperature is increased to 150 ℃, it is confirmed that the COP sample 61 is deformed although the bonding is achieved. Thus, at an additional pressure of 1600 (N/cm)²) In the case of (3), the appropriate temperature range may be 90 ℃ to 150 ℃. In particular, by setting the heating temperature to 95 ℃ or higher and 150 ℃ or lower, sufficiently strong bonding can be achieved without deforming the COP sample 61.

<4. modified example >

In the above embodiment, the method of joining the cover plate 81 and the electrode plate 82 to obtain the biosensor 8 by applying the method of the present invention has been described, but the application range of the method of the present invention is not limited thereto, and the method can be widely applied to the case of joining a member having a joined surface formed of COP and a member having a joined surface formed of metal.

In the above embodiment, the method of the present invention was applied to join the surface to be joined (1 st surface to be joined 810) made of COP and the surface to be joined (2 nd surface to be joined 820) made of metal (Ru, Ni-W, Au, silver, etc.) serving as an electrode, but the method of the present invention may be applied to join the surface to be joined made of various metals other than metal serving as an electrode and the surface to be joined made of COP.

In the above embodiment, the plasma processing apparatus 100 has the lower electrode 3 on which the object to be processed is placed grounded and the high-frequency power supply 42 is connected to the upper electrode 4, and plasma processing in the pe (plasma etching) mode is performed on the plates 81 and 82, but plasma processing in the rie (reactive Ion etching) mode may be performed by connecting the high-frequency power supply to the lower electrode 3 on which the object to be processed is placed and grounding the upper electrode 4.

In step S2 of the above embodiment, the 1 st surface to be bonded 810 and the 2 nd surface to be bonded 820 are passed through H₂O plasma or O₂The plasma is treated, but may be treated by including H₂O plasma or O₂At least one of the plasmas is mixed with the plasma to perform the treatment. For example, can be represented by H₂O plasma and O₂The mixed plasma of the plasma can also be used in H₂O plasma (or O)₂Plasma) mixed with nitrogen (N)₂) Ammonia (NH)₃) Hydrogen (H)₂) And various atmospheres of gases such as argon (Ar) and helium (He).

In step S23 of the above embodiment, the two joined surfaces to be joined 810 and 820 are heated and pressurized at the same time, but in some cases, the pressurization may be performed after the heating, or the heating may be performed after the pressurization.

Description of the reference numerals

8: biological sensor

801: terminal part

802: sample holding space

81: covering plate

810: 1 st surface to be joined

811: concave part

82: electrode plate

820: no. 2 to-be-bonded surface

821: base plate

822: electrode for electrochemical cell

823: reactive substance

100: plasma processing apparatus

71a, 71 b: heating device

72a, 72 b: metal block

73: pressing member

74: and a guide post.