JP4677251B2 - Flow cell, flow cell manufacturing method, and fluid concentration measuring apparatus - Google Patents

Description

  The present invention relates to, for example, a flow cell attached to a pipe for measuring an object to be measured in a fluid used in a manufacturing process of a semiconductor or a liquid crystal display device, a method for manufacturing the flow cell, and a fluid concentration measuring apparatus including the flow cell. .

  In general, in the manufacturing process of semiconductors, liquid crystal display devices, etc., it is a widely requested issue in these manufacturing fields to accurately, easily and quickly measure the concentration of the chemical contained in the fluid used, that is, the aqueous chemical solution for processing. is there.

  Regarding processing solutions such as acids, such as hydrofluoric acid, nitric acid, acetic acid, phosphoric acid, hydrochloric acid, and sulfuric acid, which are used in silicon wafer cleaning processes, photoetching processes, and liquid crystal display manufacturing processes in the semiconductor field From the standpoints of improving product yield, safety, and work efficiency, it is essential to control the concentration of acid in these processing solutions, and to achieve a predetermined concentration based on this concentration analysis and concentration analysis. There is a demand for automation to automatically supply acid.

As one of methods for measuring the concentration of an object to be measured contained in a fluid such as the treatment liquid, there is a method of irradiating a fluid flowing through a pipe with light and measuring the transmitted light intensity (see, for example, Patent Document 1). .) In order to measure the transmitted light intensity, a flow cell is provided in the pipe. Here, the flow cell is a channel portion formed of a light transmissive material used for irradiating a sample liquid with light.
The flow cell is provided with a light path provided so that light passes through the fluid perpendicular to the fluid flow direction, and reducing the fluctuation of the light path length increases the intensity of transmitted light that passes through the fluid with high accuracy. It is one of the requirements for measuring. Usually, the optical path length is smaller than the inner diameter of the pipe, and in the conventional flow cell, the required optical path length can be obtained by narrowing the pipe to a flat shape or interposing a small diameter pipe in the middle. Have gained. However, in such a flow cell, there is a problem in that the pressure loss of the fluid is increased because the flow cell becomes a resistance to the fluid flowing through the pipe.

In order to solve such a problem of pressure loss, a flow cell is also proposed in which a fluid passage having a cross-sectional area substantially equal to the flow passage cross-sectional area of the pipe is provided around the light transmission portion (see, for example, Patent Document 2). . As described above, the optical path length is one of the important requirements in the measurement accuracy, but the optical path length is likely to change due to the influence of the temperature of the fluid in the pipe. Therefore, also in the flow cell disclosed in Patent Document 2, the light transmission part is formed of a material having a low coefficient of thermal expansion such as quartz so that the optical path length does not fluctuate.
JP-A-6-265471 JP 7-12713 A

However, even in the flow cell disclosed in the above-mentioned Patent Document 2, as shown in FIG. 11, the light transmission part 12 of the flow cell is arranged in the pipe, and even if the problem of pressure loss is reduced, There is a problem of placing foreign matter in a form that contacts the fluid. That is, when the fluid is a processing solution used in, for example, the silicon wafer cleaning process as described above, it is absolutely necessary to avoid mixing organic substances and metals in the cleaning process. It is not preferable that foreign substances other than liquid exist. In addition, the above-mentioned materials that can withstand acid such as hydrofluoric acid include fluororesin, quartz, and sapphire. For example, quartz is eroded by hydrofluoric acid. A flow cell having 12 cannot be used. Moreover, since aluminum elutes in sapphire, the measured fluid must be discarded. As described above, in the configuration in which the light transmitting portion is provided in the pipe, there are problems that the applicable fluid is limited and that the fluid cannot be used after being circulated.
In addition, when a flow cell having a shape different from the piping shape is provided, even after the fluid is discharged from the piping, a liquid pool is generated in the flow cell portion. Etc. may occur, and there is a concern that the entire system provided with the flow cell may be adversely affected.

  Furthermore, in order to solve the above-mentioned problems, it is possible to perform measurement without any work on the piping itself by configuring the piping to be set in the part where the light projecting unit and the light receiving unit are installed in advance. There is also a measuring instrument. However, in such a configuration, the tube wall, the light projecting unit, and the light receiving unit are not in close contact with each other. Therefore, the light irradiated from the light projecting unit to the pipe and the pipe and the fluid are incident on the light receiving unit. There is a concern that the intensity of light itself may fluctuate. Also, as described above, because the pipe itself expands and contracts due to the action of the temperature and pressure of the fluid in the pipe, due to the poor adhesion between the pipe wall, the light projecting part and the light receiving part, There is also a concern that the optical path length fluctuates. Therefore, it is considered that such a measuring device cannot obtain satisfactory measurement value accuracy.

  The present invention has been made to solve the above-described problems. A flow cell, a flow cell manufacturing method, and a fluid concentration measurement capable of measuring an object to be measured in a fluid with higher accuracy than conventional methods. An object is to provide an apparatus.

In order to achieve the above object, the present invention is configured as follows.
That is, the flow cell according to the first aspect of the present invention includes a tube made of a plastic and translucent material and through which a fluid of an object to be measured flows.
A pair of light projecting and receiving members sandwiching the tube from the direction intersecting the tube and being formed in close contact with the tube and integrally formed with the tube, and passing measurement light for measuring the physical properties of the fluid;
A holding member that is attached to the light projecting / receiving member, and that keeps the distance between the pair of light projecting / receiving members constant at all times regardless of the deformation of the tube;
With
The light projecting / receiving member is fused and fixed to the tube;
It is characterized by that.
Further, the flow cell according to another aspect of the present invention includes a tube made of a plastic and translucent material through which a fluid of an object to be measured flows,
A pair of light projecting and receiving members sandwiching the tube from the direction intersecting the tube and being formed in close contact with the tube and integrally formed with the tube, and passing measurement light for measuring the physical properties of the fluid;
A holding member that is attached to the light projecting / receiving member, and that keeps the distance between the pair of light projecting / receiving members constant at all times regardless of the deformation of the tube,
The light projecting and receiving members are formed in a lens shape or a plate shape, are arranged to face each other in parallel, and are made of a fluororesin.

  An adhesion improver interposed between the outer surface of the tube and the light projecting / receiving member to improve the adhesion between the outer surface of the tube and the light projecting / receiving member and to fix the light emitting / receiving member to the tube; Furthermore, you may have.

  The light projecting / receiving member may pass the measurement light in at least one of a visible region, an infrared region, and an ultraviolet region. The tube may be made of a fluororesin. In addition, the light projecting / receiving member may have a lens shape or a plate shape, and may be disposed to face each other in parallel, and is further formed of a glass material containing quartz, sapphire, boron and silicon, or calcium fluoride. be able to. The light projecting / receiving member can be made of a fluororesin.

Furthermore, the concentration measuring apparatus according to the second aspect of the present invention includes the flow cell according to the first aspect described above,
A tube provided in the flow cell, and a light receiving unit that receives measurement light that has passed through the fluid flowing through the tube and has passed through a light receiving member of the light projecting and receiving member provided in the flow cell;
A concentration measuring unit that is electrically connected to the light receiving unit and obtains the concentration of the object to be measured based on the intensity of the measurement light detected by the light receiving unit;
It is provided with.

Furthermore, the flow cell manufacturing method according to the third aspect of the present invention includes a distance between members between a pair of light projecting and receiving members provided in a pipe made of a plastic and translucent material and in which a fluid of an object to be measured flows. Insert the distance regulating core material to regulate
As the tube is softened, the light projecting / receiving member is sandwiched between the light projecting / receiving member along the direction crossing the tube from the outside of the tube so as to face the distance regulating core member. Is formed integrally with the tube by pressing the tube against the tube so that the light projecting / receiving member is brought into close contact with the tube and fused in a defoamed state,
After the formation, a holding member for always holding the distance between the members constant regardless of the deformation of the tube is attached to the light projecting and receiving member.
It is characterized by that.
According to another aspect of the present invention, there is provided a flow cell manufacturing method comprising: a member between a pair of light projecting and receiving members provided in a pipe made of a plastic and translucent material and in which a fluid of an object to be measured flows. Insert a distance regulating core to regulate the distance,
As the tube is softened, the light projecting / receiving member is sandwiched between the light projecting / receiving member along the direction crossing the tube from the outside of the tube so as to face the distance regulating core member. Pressing the tube against the tube so that the light projecting / receiving member is brought into close contact with the tube and formed integrally with the tube,
After the formation, a holding member for always holding the distance between the members constant regardless of the deformation of the tube is attached to the light projecting / receiving member,
The light projecting / receiving member is formed in a lens shape or a plate shape, arranged in parallel with each other, and made of a fluororesin.

  According to the flow cell of the first aspect of the present invention, the concentration measuring device of the second aspect, and the flow cell manufacturing method of the third aspect, the light projecting / receiving member and the holding member are provided, and the light projecting / receiving member is integrated with the tube. Since the light projecting / receiving member is supported by the holding member, the distance between the light projecting / receiving members can be kept constant even when the tube is deformed by the temperature or pressure of the fluid. . Therefore, it is possible to measure the concentration of the object in the fluid with higher accuracy than in the past. In addition, since there is no measurement component inside the tube, no pressure loss or change in flow velocity occurs. Therefore, the entire system provided with the flow cell is not adversely affected. Furthermore, since there is no measurement component inside the tube, the problem of the measurement component eluting into the fluid does not occur. Therefore, the applicable fluid is not limited.

  As a method for integrally forming the light projecting / receiving member and the tube, it is simple to use an adhesion improver. Moreover, by fusing, both can be united more firmly and the influence with respect to measurement light can be reduced.

A flow cell, a method for producing the flow cell, and a fluid concentration measuring apparatus including the flow cell, which are embodiments of the present invention, will be described below with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected about the same component.
In this embodiment, as an object to be measured in the fluid, an acid used in a silicon wafer cleaning process, a photo etching process, a liquid crystal display manufacturing process, or the like, such as hydrofluoric acid, nitric acid, acetic acid, phosphoric acid, hydrochloric acid. An acid in a processing solution such as a mixture of sulfuric acid is taken as an example. The case where the acid concentration is measured using the flow cell is taken as an example. Therefore, in the present embodiment, the flow cell is a fluid concentration measurement flow cell.
However, the fluid and the object to be measured are not limited to the treatment liquid and the acid, and the measurement item in the object to be measured is not limited to “concentration”. Therefore, the flow cell can also be used to measure the object to be measured contained in the fluid flowing through the pipe based on the intensity of transmitted light.

First, the fluid concentration measurement flow cell will be described.
As shown in FIGS. 1 and 2, the fluid concentration measurement flow cell 120 of the present embodiment includes a tube 110, a light projecting / receiving member 121, and a holding member 122 as a basic configuration. The flow cell part in the fluid concentration measuring apparatus 101 of the embodiment is configured. As described above, the flow cell is a channel portion formed of a light transmissive material used for irradiating a sample liquid with light.

  The pipe 110 is the same pipe as the pipe 114 through which the fluid 115 containing the object to be measured flows in the fluid concentration measuring apparatus 101 to be described later, and there are various pipes depending on the type of the fluid containing the object to be measured, the use conditions, and the like. What consists of a material and a dimension can be selected suitably. In the present embodiment, the tube 110 is made of a plastic and translucent material. For example, the tube 110 is made of a fluororesin and has a diameter of about 1/4 to 1 inch. As the fluororesin material, for example, perfluoro resin (PFA), polytetrafluoroethylene (PTFE), or fluorinated ethylene propylene (FEP) is preferable.

  The light projecting / receiving member 121 includes a pair of light projecting members 121-1 and a light receiving member 121-2 made of a translucent material, and extends along an intersecting direction 129 intersecting the tube 110 from the outside of the tube 110. This is a member that is formed integrally with the tube 110 with the tube 110 interposed therebetween and in close contact with the tube 110. The light projecting / receiving member 121 installed in this way allows measurement light 133 for measuring the physical properties of the object to be measured in the fluid in the tube 110 to pass therethrough. In the present embodiment, the intersecting direction 129 is a direction in which the optical axis 133a of the measurement light 133 is orthogonal to the axial direction 111 of the tube 110, and as shown in FIG. The light receiving member 121-2 is disposed opposite and parallel to each other at the same position in the axial direction 111 of the tube 110. However, the intersecting direction 129 is not limited to the orthogonal direction, and the light projecting member 121-1 and the light receiving member 121-2 are arranged so as to be shifted from each other in the axial direction 111 of the tube 110. The optical axis 133a and the axial direction 111 may be configured to intersect at an angle other than 90 degrees.

  As in the case of the conventional flow cell, also in the flow cell 120 for measuring the fluid concentration, the distance between the light projecting / receiving members 121, that is, the member between the light projecting member 121-1 and the light receiving member 121-2. It is very important for measurement accuracy that the distance 126 does not vary. Therefore, in this embodiment, in order to keep the inter-member distance 126 unchanged, the method for attaching the light projecting / receiving member 121 to the tube 110 is devised and the holding member 122 is provided. These will be described in detail later.

  The measurement light 133 is light in at least one of the visible region, the infrared region, and the ultraviolet region, and the material of the light projecting / receiving member 121 is selected according to the type of the measurement light 133. In the present embodiment, the light projecting / receiving member 121 is made of a material such as quartz, sapphire, for example, BK7, an optical glass material containing boron and silicon, calcium fluoride, or a fluororesin. As the fluororesin material, for example, perfluoro resin (PFA), polytetrafluoroethylene (PTFE), or fluorinated ethylene propylene (FEP) is preferable.

  In each of the above materials, BK7 is most commonly used for the light projecting / receiving member 121. BK7 transmits light in the visible region and near infrared region. On the other hand, when handling light in the ultraviolet region shorter than the visible region and in the middle infrared region longer than the near infrared region, it is necessary to use an optical member other than BK7. Quartz is a material that can be measured even in the ultraviolet region. Quartz can transmit light in the ultraviolet region, visible region, and near infrared region. There is a disadvantage that it dissolves in hydrofluoric acid. Sapphire is a material that is durable against hydrofluoric acid. Sapphire can transmit light in the ultraviolet region, the visible region, and the near infrared region. Calcium fluoride can transmit a wide range of light from the ultraviolet region, visible region, near infrared region, and mid-infrared region, but has the property of dissolving in water, and in a humid environment It is not preferable. In addition, the fluororesin material is inferior in light transmittance to the above-mentioned materials.

  As will be described later, as one method for bringing the light projecting / receiving member 121 into close contact with the tube 110, there is a method of fusing. In this case, when the properties of both are the same or close, it is possible to obtain better fusion properties. Therefore, when the tube 110 is made of, for example, a fluororesin, the light projecting / receiving member 121 is also preferably made of a fluororesin.

  Further, the light projecting / receiving member 121 can take a plate shape or a lens shape as shown in FIG. The plate shape is preferable because the influence on the inter-member distance 126 due to a disturbance such as an impact is small. Although FIG. 4 shows a convex lens, a concave lens can be used. In the present embodiment, the light projecting member 121-1 and the light receiving member 121-2 are both plate-like members having the same shape, but may be different from each other.

  In addition, the size of the light projecting / receiving member 121 may be at least a dimension necessary for the measurement light 133 to pass from the function of the light projecting / receiving member 121 that transmits the measurement light 133. For example, about 5 mm. Therefore, the light projecting / receiving member 121 is about 5 mm square or more, or about 5 mm in diameter, and has a size that substantially corresponds to the diameter of the tube 110. Further, when the light projecting / receiving member 121 has a plate shape, the thickness of the light projecting / receiving member 121 can withstand it because the pressure when the tube 110 is clamped by the light projecting / receiving member 121 varies depending on the outer diameter and thickness of the tube 110. It needs to be thick. However, since the amount of light reduction increases as the thickness increases, an appropriate thickness is selected. In this embodiment, it is 2-5 mm, for example.

  As a method for bringing the light projecting / receiving member 121 into close contact with the tube 110 and forming it integrally with the tube 110, a method using an adhesion improver 123 as shown in FIG. 1, and a light projecting / receiving member 121 as shown in FIG. There is a method of forming the fused portion 124 by fusing the tube 110. The adhesion improver 123 is interposed between the outer surface 110a of the tube 110 and the light projecting / receiving member 121 to improve the adhesion between the tube outer surface 110a and the light projecting / receiving member 121 and to the tube 110. 121 is a substance for fixing 121. As an example, adhesives such as epoxy, silicon, and cyanoacrylate can be used. In FIG. 1 and FIG. 3, the adhesion improving agent 123 and the fused portion 124 are exaggerated from the actual situation for the sake of clarity.

Further, as described above, since the measurement light 133 is transmitted through the light projecting / receiving member 121, if bubbles are mixed in the adhesion improving agent 123 and the fused portion 124, light is refracted and scattered, and the measurement accuracy is deteriorated. Therefore, it is important to defoam any method. For example, defoaming can be performed using a stirring defoaming device, and examples of the stirring defoaming device include defoaming using, for example, centrifugal force action as disclosed in Japanese Patent Nos. 2711964 and 3213735. A device that performs the operation can be used.
A specific method for forming the light projecting / receiving member 121 integrally with the tube 110 will be described later.

The holding member 122 is a member that is attached to the light projecting / receiving member 121 and that constantly holds the inter-member distance 126 between the pair of light projecting / receiving members 121 regardless of the deformation of the tube 110. In the present embodiment, the reference position of the inter-member distance 126 is the facing surface of each of the light projecting / receiving members 121 facing each other, but is not limited to this, and an arbitrary position in the light projecting / receiving member 121 is used as a reference. Can be taken.
As described above, in the flow cell, it is very important in terms of measurement accuracy that the inter-member distance 126 does not vary. On the other hand, the tube 110 is deformed by the influence of the temperature, pressure, etc. of the fluid flowing inside. Therefore, even if the light projecting / receiving member 121 is formed integrally with the tube 110 as described above, if there is no member that supports the light projecting / receiving member 121, the member is accompanied by the deformation of the tube 110. The distance 126 also varies. Therefore, the holding member 122 that always maintains the inter-member distance 126 constant regardless of the deformation of the tube 110 is attached to the light projecting / receiving member 121.

  As shown in FIG. 1, the holding member 122 is a member having a U-shaped cross section and extending along the tube 110, and includes an attachment member 1221 and a connection member 1222, and the attachment member 1221 and the connection member 1222 and the holding member 122 are integrally formed. Such a holding member 122 has a function of holding the inter-member distance 126 constant at all times regardless of the deformation of the tube 110 as described above, and is therefore a rigid member, such as a metal material such as aluminum or stainless steel. Etc.

The attachment member 1221 is a pair of flat plate-like members that are opposed to and parallel to each other so as to sandwich the tube 110, and the light projecting / receiving member 121 is fixed to each of the opposing surfaces 1221a. The fixing is performed by a method in which the light projecting / receiving member 121 is held by the mounting member 1221 with a pressing force that does not easily move the light projecting / receiving member 121 with respect to the mounting member 1221. Further, an adhesive may be applied to a portion of the light projecting / receiving member 121 where the measurement light 133 does not pass and fixed to the mounting member 1221. In order to increase the frictional force between the mounting member 1221 and the light projecting / receiving member 121 and to prevent the light projecting / receiving member 121 from shifting, for example, a groove or the like is preferably formed in the mounting member 1221.
Each attachment member 1221 is formed with a through hole 1223 at a portion corresponding to the light projecting / receiving member 121 to pass through the attachment member 1221 in the thickness direction and pass the optical axis 133 a of the measurement light 133. The cross-sectional shape of the through hole 1223 is not specified, and may be, for example, a circular shape having a diameter of about 5 mm at a minimum. Of course, the size of the through hole 1223 is smaller than that of the light projecting / receiving member 121.

  Further, when the light projecting / receiving member 121 has a lens shape, the opposing surface 1221a of the mounting member 1221 may be provided with unevenness according to the shape of the lens surface. For example, when the light projecting / receiving member 121 is a convex lens as shown in FIG. 4, a concave portion corresponding to the shape of the lens surface may be formed on the opposing surface 1221a.

  The connecting member 1222 is a member that connects the mounting members 1221 such that the facing surfaces 1221a of the mounting member 1221 are opposed to each other and arranged in parallel. The connecting member 1222 defines the inter-member distance 126 and the variation of the defined inter-member distance 126. It is a member that prohibits Depending on the diameter of the tube 110, the inter-member distance 126 is about 2 to 20 mm in this embodiment. In the present embodiment, as shown in FIG. 1, the attachment member 1221 and the connecting member 1222 are integrally formed, and therefore the inter-member distance 126 cannot be changed by the holding member 122. However, for example, the connecting member 1222 has a structure that can be expanded and contracted, or one attachment member 1221 has a structure that can move relative to the connecting member 1222 so that the distance between the opposing surfaces 1221a of the attachment member 1221 can be changed. Thus, the holding member 122 having a structure in which the inter-member distance 126 is variable can be obtained. However, even when the member-to-member distance 126 is variable, the once-defined member distance 126 does not vary with the deformation of the tube 110.

  With the configuration described above, the fluid concentration measurement flow cell 120 is formed.

  Hereinafter, a method according to this embodiment in which the light projecting / receiving member 121 is formed integrally with the tube 110 will be described with reference to FIGS. Here, the plate-shaped light projecting / receiving member 121 is taken as an example, but any shape of the light projecting / receiving member 121 can be applied.

  In step S1 of FIG. 6, a pipe 110 constituting the fluid concentration measurement flow cell 120 is prepared, and a distance regulating core 190 is inserted into the pipe 110 as shown in FIG. The distance-defining core member 190 is a member for defining the inter-member distance 126 of the pair of light projecting / receiving members 121 arranged to face the tube 110 as described above, and will be described below. In this way, it is a member that serves as a base when the light projecting / receiving member 121 is pressed against the tube 110. The distance regulating core 190 is a size corresponding to the inter-member distance 126 and a shape in which the pair of light projecting / receiving members 121 are arranged in parallel to face each other, that is, a square member, and are parallel to each other. It has two opposing flat surfaces 190a and 190b, and is made of a metal material such as aluminum or stainless steel, glass or the like. The distance between the two opposing flat surfaces 190a and 190b is the dimension of the inter-member distance 126-α. Here, α is a value obtained by doubling the added value of the tube thickness of the tube 110 and the thickness of the adhesion improving agent 123 when the adhesion improving agent 123 is interposed. Further, as will be described below, the distance regulating core member 190 has a through hole 190c along the axial direction 111 of the tube 110 so that the tube 110 can be effectively heated. A cylindrical square may be used.

  When the light projecting / receiving member 121 has a lens shape, the flat surfaces 190a and 190b of the distance defining core member 190 may be provided with irregularities according to the shape of the lens surface. For example, when the light projecting / receiving member 121 is a convex lens as shown in FIG. 4, concave portions corresponding to the shape of the lens surface may be formed on the flat surfaces 190 a and 190 b.

  In step S <b> 2, for example, hot air of about 200 to 360 ° C. is blown into the tube 110 to soften the tube 110. In parallel with the softening operation, each projecting / receiving member 121 has a contact surface 121a with the outer surface 110a of the tube 110, or an outer surface 110a of the tube 110 with which the contact surface 121a is pressed, or both. The adhesion improver 123 is applied. After the application, while continuing the softening operation, as shown in FIG. 8, a contact surface 121a is disposed so as to face the flat surfaces 190a and 190b of the distance regulating core member 190, and the light projecting and receiving members 121 are arranged. And sandwich the tube 110. At this time, as described above, bubbles are not sealed between the contact surface 121a and the tube outer surface 110a. After the clamping, each light projecting / receiving member 121 is pressed against the outer surface 110a of the tube 110 along a pressing direction 191 orthogonal to the planes 190a and 190b by a press machine. In the present embodiment, as an example, the pressing operation is performed at a pressing force of about 0.1 to 1 MPa in about 2 to 5 minutes. In the present embodiment, the pressing direction 191 is a direction parallel to the crossing direction 129 described above.

By the pressing operation, the contact surface 121a of each light projecting / receiving member 121 and the outer surface 110a of the tube 110 are brought into close contact with each other, and each light projecting / receiving member 121 is formed integrally with the tube 110.
When the integral formation is performed using the adhesion improver 123, it can be performed more easily than the fusion described below.

On the other hand, when the light projecting / receiving member 121 is fused to the tube 110, only the tube 110 is melted, only the light projecting / receiving member 121 is melted, or both the tube 110 and the light projecting / receiving member 121 are melted. Three forms are possible. Although the tube softening temperature and the pressing force vary depending on which form is adopted, in general, the tube softening temperature and the pressing force are larger in the case of fusing than the above-described case using the adhesion improver 123. Become. For example, when only the tube 110 is melted and the light projecting / receiving member 121 is fused to the tube 110, the tube 110 is softened by blowing hot air of about 200 to 360 ° C. into the tube 110. The pressing operation of the member 121 to the tube 110 is performed at a pressing force of about 0.1 to 1 MPa in about 2 to 5 minutes.
Even in the case where the integral formation is performed by fusion, it is necessary to prevent bubbles from being sealed in the fusion portion 124.

  Thus, when performing the above-mentioned integral formation by fusion, the light projecting / receiving member 121 and the tube 110 can be more integrally formed as compared with the case of using the adhesion improving agent 123 described above. In addition, since the junction portion does not include substances other than the light projecting / receiving member 121 and the tube 110, it is not necessary to consider the influence on the measurement light 133 passing through the junction portion. Therefore, the measurement accuracy can be further improved as compared with the case where the adhesion improving agent 123 is used.

  After the integral formation, in step S3, the softening operation is stopped, and the distance defining core 190 is taken out from the tube 110 as shown in FIG.

In the next step 4, as shown in FIG. 10, the holding member 122 is fixed to the light projecting / receiving member 121 in order to fix the inter-member distance 126 in the pair of light projecting / receiving light members 121 formed integrally with the tube 110. Install. In the present embodiment, as described above, step S4 is executed after the distance-defining core 190 is taken out from the tube 110. However, in step S3, only the softening operation is stopped to determine the distance. You may transfer to step S4, without taking out the core material 190. FIG. And after completion | finish of step S4, you may take out the core material 190 for distance regulation from the inside of the pipe | tube 110. FIG.
The fluid concentration measurement flow cell 120 is formed by the manufacturing method described above.

  In the fluid concentration measurement flow cell 120 configured as described above, in particular, (1) the same pipe 110 as the pipe through which the fluid containing the object to be measured flows is used, and (2) the measurement is performed on the outer surface 110a of the pipe 110. A member to which a measuring member is attached and no measurement member is provided in the flow path portion inside the tube 110, (3) a point where the light projecting / receiving member 121 is formed integrally with the tube 110, and ( 4) It has a characteristic configuration in that a holding member for prohibiting the fluctuation of the inter-member distance 126 is attached to the light projecting / receiving member 121 formed integrally with the tube 110. According to such a fluid concentration measurement flow cell 120, the inter-member distance 126 varies even when the tube 110 is deformed due to the temperature, pressure, etc. of the fluid, particularly by the configurations of (3) and (4) above. Disappear. Therefore, the flow cell 120 for measuring the fluid concentration contributes so that the concentration of the object to be measured in the fluid can be measured with higher accuracy than in the past.

  In addition, with the above-described configurations (1) and (2), even in a system in which the fluid concentration measurement flow cell 120 of this embodiment is installed, fluid pressure loss occurs in the fluid concentration measurement flow cell 120 portion. In addition, there are no places where liquid pools occur. Thus, for example, fluid pressure loss in the flow cell portion does not adversely affect the entire system. Further, a part of the flow cell does not elute into the fluid, and according to the fluid concentration measurement flow cell 120, the applicable fluid is not limited. In addition, since no liquid pool occurs, for example, a pipe cleaning operation can be easily performed.

  The fluid concentration measuring flow cell 120 configured as described above can be provided to constitute a fluid concentration measuring device that measures the concentration of the object to be measured in the fluid. A fluid concentration measurement apparatus 101 shown in FIG. 5 includes a pipe 114, the above-described fluid concentration measurement flow cell 120, a detection unit 130 including the fluid concentration measurement flow cell 120, a processing unit 140, a concentration measurement unit 150, And a control unit 160. The control unit 160 controls operations of the detection unit 130, the concentration measurement unit 150, and the like. The basic structure of the fluid concentration measuring apparatus including the fluid concentration measuring flow cell 120 described above is provided in the pipe 114, the fluid concentration measuring flow cell 120, the concentration measuring unit 150, and the detecting unit 130 as described below. What is necessary is just to provide the light-receiving part 132. FIG.

  The pipe 114 is a pipe made of the same material, shape, and size as the pipe 110 provided in the fluid concentration measurement flow cell 120. In this embodiment, the pipe 114 is sent from the processing unit 140 and passes through the fluid concentration measurement flow cell 120. The circulating system is configured so that the fluid 115 returned to the processing unit 140 again. The circulation system is provided with a pump for circulating the fluid 115. Of course, the fluid concentration measurement flow cell 120 may be installed in a part of the non-circulation system without forming such a circulation system.

The detection unit 130 includes the fluid concentration measurement flow cell 120 described above, a light projecting unit 131, and a light receiving unit 132.
The light projecting unit 131 is disposed corresponding to the light projecting member 121-1 in the fluid concentration measurement flow cell 120, and emits measurement light 133 from a light source composed of, for example, a tungsten / halogen lamp. The light projecting unit 131 has an appropriate light projecting side optical system for allowing the measurement light 133 generated by the light source to pass through the through hole 1223 provided in the fluid concentration measurement flow cell 120.

  The light receiving unit 132 is disposed corresponding to the light receiving member 121-2 in the flow cell 120 for measuring the fluid concentration, and is emitted from the light projecting unit 131. The through hole 1223, the light projecting member 121-1, the tube 110, and the fluid 115 are disposed. The measurement light 133 that has passed through the light receiving member 121-2 and the through hole 1223 is received. The light receiving unit 132 includes a light receiving element and an appropriate light receiving side optical system for condensing the measurement light 133 on the light receiving element. The light receiving unit 132 is electrically connected to the concentration measuring unit 150, and sends an electric signal corresponding to the intensity of the received measurement light 133 to the concentration measuring unit 150.

  The processing unit 140 is a part installed corresponding to the object to be measured. For example, when measuring the concentration of the cleaning liquid of the semiconductor wafer, the processing unit 140 is a semiconductor wafer cleaning process unit.

  The concentration measuring unit 150 obtains the concentration of the object to be measured in the fluid 115 flowing in the pipe 114 based on the electrical signal supplied from the light receiving unit 132. As the concentration determination method, for example, various known methods such as a method using a known relationship between the electric signal and the concentration can be adopted.

  The present invention is applicable to, for example, a fluid concentration measurement flow cell attached to a pipe for measuring the concentration of a fluid used in a manufacturing process of a semiconductor, a liquid crystal display device, and the like, and a fluid concentration measurement apparatus including the flow cell.

It is a front view which shows the structure of the flow cell for fluid concentration measurement in embodiment of this invention, Comprising: It is a figure at the time of interposing an adhesion improving agent between the member for light projection / reception and a pipe | tube. It is a top view of the flow cell for fluid concentration measurement shown in FIG. It is a front view which shows the structure of the flow cell for fluid concentration measurement in embodiment of this invention, Comprising: It is a figure at the time of fuse | melting the light-receiving / light-receiving member and a pipe | tube. It is a front view which shows the structure of the flow cell for fluid concentration measurement in embodiment of this invention, Comprising: It is a figure at the time of using a lens as a member for light projection / reception. FIG. 5 is a diagram illustrating a configuration of a fluid concentration measuring apparatus including any one of the fluid concentration measuring flow cells illustrated in FIGS. 1, 3, and 4. 5 is a flowchart for explaining a method of integrally forming a light projecting / receiving member in close contact with a pipe in the fluid concentration measurement flow cell shown in FIGS. 1, 3, and 4. It is a perspective view for demonstrating the process in the flowchart shown in FIG. It is a perspective view for demonstrating the process in the flowchart shown in FIG. It is a perspective view for demonstrating the process in the flowchart shown in FIG. It is a perspective view for demonstrating the process in the flowchart shown in FIG. It is a figure which shows the structure of the conventional flow cell.

Explanation of symbols

101 ... Fluid concentration measuring device, 110 ... Tube, 115 ... Fluid,
120 ... Flow cell for measuring fluid concentration, 121 ... Projecting / receiving member,
121-2: light receiving member, 122 ... holding member, 123 ... adhesion improver,
126 ... Distance between members, 129 ... Crossing direction, 132 ... Light receiving part, 133 ... Measuring light,
150 ... concentration measuring unit, 190 ... core for distance regulation.

Claims (11)

A pipe (110) made of a plastic and translucent material and through which the fluid (115) of the object to be measured flows;
A pair of light projecting and receiving light that sandwiches the tube from the direction (129) intersecting the tube and is in close contact with the tube and is integrally formed with the tube and allows the measurement light (133) for measuring the physical properties of the fluid to pass therethrough. Member (121);
A holding member (122) that is attached to the light projecting / receiving member and that holds the inter-member distance (126) between the pair of light projecting / receiving members constant at all times regardless of the deformation of the tube;
With
The light projecting / receiving member is fused and fixed to the tube;
A flow cell characterized by that. A pipe (110) made of a plastic and translucent material and through which the fluid (115) of the object to be measured flows;
A pair of light projecting and receiving light that sandwiches the tube from the direction (129) intersecting the tube and is in close contact with the tube and is integrally formed with the tube and allows the measurement light (133) for measuring the physical properties of the fluid to pass therethrough. Member (121);
A holding member (122) that is attached to the light projecting / receiving member and that holds the inter-member distance (126) between the pair of light projecting / receiving members constant at all times regardless of the deformation of the tube;
With
The light projecting / receiving member is formed in a lens shape or a plate shape and is arranged to face each other in parallel, and is made of a fluororesin.
A flow cell characterized by that. The flow cell according to claim 1, wherein the light projecting and receiving member allows the measurement light in at least one of a visible region, an infrared region, and an ultraviolet region to pass therethrough . The flow cell according to claim 1 or 3, wherein the tube is made of a fluororesin . The emitting and receiving member is made by the lens shape or a plate shape are arranged in parallel to face each other, the flow cell according to any one of claims 1, 3 and 4. An adhesion improver (123) interposed between the outer surface of the tube and the light projecting / receiving member to improve the adhesion between the outer surface of the tube and the light projecting / receiving member and to fix the light emitting / receiving member to the tube. The flow cell according to claim 2, further comprising: The flow cell according to claim 2, wherein the light projecting / receiving member transmits the measurement light in at least one of a visible region, an infrared region, and an ultraviolet region . Said tube is made at fluorocarbon resin, the flow cell according to any of claims 2,6,7. A flow cell (120) according to any of the preceding claims;
  The measurement light (133) transmitted through the pipe (110) provided in the flow cell and the light receiving member (121-2) among the light projecting and receiving members provided in the flow cell through the fluid (115) flowing through the pipe. A light receiving unit (132) for receiving light;
  A concentration measuring unit (150) that is electrically connected to the light receiving unit and obtains the concentration of the object to be measured based on the intensity of the measurement light detected by the light receiving unit;
  A fluid concentration measuring device comprising: The distance (126) between the pair of light projecting / receiving members (121) provided in the pipe is defined in the pipe (110) made of a plastic and translucent material and through which the fluid (115) of the object to be measured flows. Insert the distance regulating core (190),
  As the tube is softened, the tube is sandwiched by the light projecting and receiving members along the direction (129) that faces the distance-defining core from the outside of the tube and intersects the tube. Pressing the light receiving member against the tube, bringing the light projecting and receiving member into close contact with the tube and fusing in a defoamed state, and integrally forming the tube,
  After the formation, a holding member (122) for holding the distance between the members constant at all times regardless of the deformation of the tube is attached to the light projecting / receiving member.
  A manufacturing method of a flow cell characterized by the above. The distance (126) between the pair of light projecting / receiving members (121) provided in the pipe is defined in the pipe (110) made of a plastic and translucent material and through which the fluid (115) of the object to be measured flows. Insert the distance regulating core (190),
  As the tube is softened, the tube is sandwiched by the light projecting and receiving members along the direction (129) that faces the distance-defining core from the outside of the tube and intersects the tube. The light receiving member is pressed against the tube, the light projecting / receiving member is brought into close contact with the tube, and formed integrally with the tube,
  After the formation, a holding member (122) for always holding the distance between the members constant regardless of the deformation of the tube is attached to the light projecting and receiving member.
  The light projecting / receiving member is in the shape of a lens or a plate and is disposed facing each other in parallel, and is made of a fluororesin.
  A manufacturing method of a flow cell characterized by the above.

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