JPWO2009057359A1 - Additive removal method, additive removal apparatus and plating system - Google Patents

Abstract

The plating system includes a plating layer forming portion that forms a plating layer on the resin film (9) by immersing the resin film (9) in a plating solution containing a template agent, and a plating layer on the resin film (9). A removal device (4) for removing the template agent is provided. The removing device (4) emits light toward the removing liquid tank (41) for storing the removing liquid (411) in which the resin film (9) is immersed, and the resin film (9) in the removing liquid (411). It has the light irradiation part (42) to irradiate. In the removal device (4), the template agent can be efficiently removed from the plating layer by promoting the detachment of the template agent from the plating layer by the light from the light irradiation section (42).

Description

  The present invention relates to a technique for removing an additive from a plating layer on an object formed by immersing the object in a plating solution containing the additive, and a plating system using the technique.

  In recent years, attention has been focused on dye-sensitized solar cells that can be used as a power source without impairing the design of various products. The dye-sensitized solar cell has a structure in which a photoelectric layer, a charge transport layer, and a counter electrode substrate having a counter electrode conductive layer are sequentially laminated on a glass substrate having a transparent conductive layer. As a method for forming a transparent conductive layer such as ITO (indium tin oxide) on a substrate, for example, sputtering, PLD (Pulsed Laser Deposition) (also called pulsed laser ablation), CVD (Chemical Vapor Deposition), Alternatively, a spray method or the like is known, and as a method for forming a photoelectric layer, a porous semiconductor layer is formed by applying semiconductor fine particles such as titanium dioxide on a substrate and firing at a high temperature, and then a semiconductor. A technique for adsorbing the dye to the layer is employed.

  In addition, it has also been proposed to manufacture a dye-sensitized solar cell at a low cost using a transparent substrate such as an inexpensive plastic. However, in this case, the above-described method involving a baking treatment cannot be employed when forming the photoelectric layer. Therefore, in Japanese Patent Application Laid-Open No. 2004-6235 (Document 1), a dye as a template compound (template agent) is mixed in an electrolytic bath containing a zinc salt, and a cathode current is applied to the substrate in the electrolytic bath. A technique for forming on the substrate a zinc oxide thin film on which the dye is adsorbed on the inner surface by performing the analysis is proposed. In Document 1, the dye is further removed from the zinc oxide thin film, and then the dye is re-adsorbed. Thus, a technique for producing a dye-sensitized solar cell that can obtain a high photoelectric exchange rate is also disclosed.

  By the way, the removal of the template agent from the zinc oxide thin film is usually performed by immersing the substrate in a weak alkaline solution (removal solution). However, such a method requires a long time to remove the template agent. End up. Also, when forming a plating layer on an object using a plating solution containing an additive other than the template agent, it may be preferable to remove the additive from the plating layer on the object. Even in such a case, it is required to efficiently remove the additive from the plating layer.

  The present invention is directed to an additive removal method for removing an additive from a plating layer on an object formed by immersing the object in a plating solution containing the additive. The purpose is to remove well.

  The additive removing method according to the present invention includes: a) immersing the object in a removing liquid stored in a removing liquid tank, or continuously applying a removing liquid to the plating layer of the object; b) irradiating the object with light that promotes the removal of the additive from the plating layer in parallel with the step a). According to the present invention, the additive can be efficiently removed from the plating layer.

  Preferably, the additive is a template agent, and in this case, the template agent can be removed from the plating layer to form a porous layer.

  In one preferable embodiment of the present invention, the light includes light having a wavelength included in the absorption wavelength band of the additive, or includes light having a wavelength included in the absorption wavelength band of the plating layer. Thereby, an additive can be more efficiently removed from a plating layer. More preferably, when the light contains ultraviolet rays, the organic additive in the plating layer can be removed more efficiently.

  In another preferred embodiment of the present invention, after the object is taken out from the plating solution, the plating layer of the object is prevented from being dried until the step a) is started. Thereby, an additive can be more efficiently removed from a plating layer.

  The present invention is also directed to an additive removal apparatus for removing an additive from a plating layer on an object formed by immersing the object in a plating solution containing the additive. The additive removal apparatus includes a removal liquid tank that stores a removal liquid in which the object is immersed, or a removal liquid application unit that is a discharge unit that continuously applies the removal liquid to the plating layer of the object. A light irradiating unit that irradiates the object in the removing liquid tank or the object to which the removing liquid is applied from the discharge unit with light that promotes the removal of the additive from the plating layer. . Thereby, an additive can be efficiently removed from a plating layer.

  The present invention is further directed to a plating system for forming a plating layer on an object. The plating system includes a plating layer forming unit that forms a plating layer on the object by immersing the object in a plating solution containing the additive, and the addition that removes the additive from the plating layer of the object By providing the agent removing device, the plating layer can be formed and the additive can be efficiently removed from the plating layer.

  The above object and other objects, features, aspects and advantages will become apparent from the following detailed description of the present invention with reference to the accompanying drawings.

It is a figure which shows a plating system. It is a figure which shows the structure of a removal apparatus. It is a figure which shows the flow of the process which forms a porous layer on a target object. It is a figure which shows the other example of the removal apparatus. It is a figure which shows the other example of a plating system. It is a figure which shows the further another example of a plating system. It is a figure which shows the other example of a plating layer formation part. It is a figure which shows the further another example of a removal apparatus. It is a figure which shows the further another example of a removal apparatus. It is a figure which shows the further another example of a plating system.

  FIG. 1 is a diagram showing a plating system 1 according to an embodiment of the present invention. The plating system 1 is a system in which a porous layer (film) is formed by plating on a transparent resin film 9 (plastic film) on which a transparent conductive layer is previously formed. A dye layer is adsorbed to the porous layer in a subsequent process to form a photoelectric layer, and the resin film 9 in which the transparent conductive layer and the photoelectric layer are laminated is cut, and a substrate having a counter electrode conductive layer is interposed through a spacer. Opposed. Thereafter, an electrolyte is injected between the rectangular resin film and the counter electrode substrate to form a charge transport layer, whereby a dye-sensitized solar cell is manufactured. Thus, the plating system 1 is used for manufacturing a dye-sensitized solar cell. “Plating” in the present invention is not limited to metal, and means that a material such as a metal oxide is generated on the electrode surface by electrolysis (that is, electrodeposition).

  As shown in FIG. 1, the plating system 1 continues from a roll 90 (also referred to as a web (WEB)) of a resin film on which a transparent conductive layer is formed in advance to each part of the resin film 9 (that is, a belt-shaped resin film). Each of a plurality of existing portions), and a plating layer forming unit 3 for forming a plating layer on the transparent conductive layer by immersing the resin film 9 in a plating solution containing a template agent, A template agent removing device 4 for removing the template agent from the plating layer on the resin film 9 (hereinafter simply referred to as “removing device 4”) and a control unit 10 that performs overall control of the plating system 1 are provided.

  In the plating system 1, the drawing portion 2, the plating layer forming portion 3, and the removing device 4 are arranged in a line in a predetermined direction, and a plurality of rollers 61 (in FIG. 1, one roller extends in a direction perpendicular to the direction). ) Is disposed over the entire plating system 1, so that each part of the resin film 9 drawn out from the drawing-out portion 2 is placed in a drying furnace 49 described later of the removing device 4. Is continuously conveyed. The roller 61 is formed of a material having corrosion resistance against a liquid (a plating liquid and a removing liquid described later) used in the plating system 1. In FIG. 1, only a part of a large number of rollers actually provided in the plating system 1 is illustrated.

The plating layer forming unit 3 includes zinc chloride (ZnCl ₂ ) and a template agent as main components (that is, chloride ions, zinc ions and a template agent as main components), and a plating tank 31 for storing a plating solution 311, A counter electrode 32 and a reference electrode (also referred to as a reference electrode) 33 disposed in the plating solution 311, and a power supply unit 34 that applies a potential to each of the counter electrode 32 and the reference electrode 33 are provided. In addition, one of the plurality of rollers 61 provided in the plating tank 31 and denoted by reference numeral 61 a is electrically connected to the power supply unit 34.

The plating tank 31 is supplied with oxygen into the plating solution 311 (so-called oxygen bubbling), an oxygen introduction pipe 312, a dissolved oxygen meter 313 for measuring the oxygen concentration in the plating solution 311, and the temperature of the plating solution 311 A thermometer 314 is attached to measure. A heater 315 is provided in the plating solution 311, and the temperature controller 316 controls the heater 315 based on the output of the thermometer 314, whereby the plating solution 311 is kept at a constant temperature. The plating layer forming unit 3 can use other types of plating solutions such as a plating solution containing zinc nitrate (Zn (NO ₃ ) ₂ ) and a template agent as main components. The template agent will be described later.

  FIG. 2 is a diagram illustrating a configuration of the removing device 4. As shown in FIG. 2, the removal device 4 includes a removal liquid tank 41 and a removal liquid tank for storing a weakly alkaline removal liquid 411 (for example, an aqueous solution of sodium hydroxide, potassium hydroxide, etc.) into which the resin film 9 is immersed. 41 is provided with a light irradiation unit 42 disposed above 41, a cleaning tank 48 for storing a cleaning liquid such as pure water, and a drying furnace 49 for drying the resin film 9 after cleaning in the cleaning tank 48.

  The removal liquid tank 41 is provided with a circulation flow path 43 that circulates the removal liquid 411 using a pump 431, and a concentration detection unit 432 that detects the concentration of the template agent in the removal liquid 411 is provided in the circulation flow path 43. Provided. Further, a removal liquid tank 433 for storing unused removal liquid is connected to the circulation flow path 43, and the concentration detection unit 432 is connected to a template agent when removing a template agent from a plating layer on the resin film 9 described later. When it is confirmed that the concentration of the template agent in the removal liquid 411 exceeds a predetermined value, a part of the removal liquid 411 in the removal liquid tank 41 is discharged to the drainage tank 434 through the circulation channel 43. In addition, it is possible to replenish unused removal liquid from the removal liquid tank 433 to the removal liquid tank 41 (that is, a part of the removal liquid 411 in the removal liquid tank 41 is replaced). As a result, stable processing can be continuously performed without stopping the plating system 1 when the removal liquid 411 is replaced, and a reduction in throughput associated with the formation of the porous layer is also prevented.

  The light irradiation unit 42 has a light source (for example, a light source having a total luminous flux of 7000 lumens or more (preferably 10,000 lumens or more)) such as a halogen lamp or a metal halide lamp, and the illuminance meter 421 emits light from the light source. The amount is made detectable. When a decrease in the intensity of light from the light irradiation unit 42 is confirmed by the output from the illuminance meter 421, that effect is displayed on the display device of the control unit 10 (see FIG. 1) and notified to the operator. As will be described later, in the removing device 4, the resin film 9 in the removing liquid 411 is irradiated with light from the light irradiation unit 42, thereby promoting the removal of the template agent from the plating layer.

  FIG. 3 is a diagram showing a processing flow in which the plating system 1 forms a porous layer on the resin film 9. FIG. 3 shows a flow of processing focusing attention on a part of the resin film 9, and in practice, all the processing in FIG. 3 is performed in parallel on corresponding portions of the resin film 9. . Note that step S11a indicated by a broken-line rectangle in FIG. 3 shows the contents of the operation performed in the plating system 1b in FIG. 6 described later, and is performed in the following processing in the plating system 1 in FIG. Absent. Further, as will be described later, since a porous layer may be formed on an object other than the resin film 9, the resin film 9 is generalized as “object” in FIG. 3.

  In the plating system 1 of FIG. 1, a part of the plurality of rollers 61 connected to the motor starts to rotate in the same direction, so that each of the resin films 9 that are objects to be processed from the roll 90 in the drawing unit 2. Sites are pulled out sequentially. Hereinafter, the subsequent processing will be described by paying attention to a part of the resin film 9 drawn out by the drawing portion 2, and this portion will be referred to as a “target portion”.

  The target portion pulled out from the roll 90 moves into the plating tank 31 and is immersed in the plating solution 311. In the power supply unit 34, a predetermined reference potential is applied to the reference electrode 33, a potential at which a difference from the reference potential is a predetermined value is applied to the counter electrode 32, and a transparent conductive layer (a target conductive region) is provided via a roller 61a. Actually, it is formed over almost the entire surface of the resin film 9.) A potential at which the difference from the reference potential is a predetermined value is also applied. As a result, electrolytic plating is performed on the target site (electrodeposition is performed), and a plating layer (electrodeposition film) containing zinc oxide and a template agent is formed on the target site (step S11). Here, the template agent is formed on the transparent conductive layer by electrolytic plating by forming a complex with zinc ions in the plating solution 311 in the same manner as the template compound in Japanese Patent Application Laid-Open No. 2004-6235 (Document 1). It is adsorbed on the inner surface of the zinc oxide film formed on the substrate and is typically a dye.

  The target portion where the plating layer is formed is pulled up from the plating tank 31 and then continuously moves to the removal liquid tank 41, and is supported by a roller 61 in the removal liquid tank 41 as shown in FIG. While being immersed in the removal liquid 411 (step S12). Actually, in the removing device 4, a plurality of paths of the resin film 9 are folded back by the plurality of rollers 61 provided in the removing liquid tank 41, and the resin film 9 can be immersed in the removing liquid 411 for a long time. It is possible. Moreover, the light irradiation part 42 (for example, arrange | positioned in the range below 1.2 meters (more preferably 0.8 meters) from a target part) with respect to a target part with respect to a target part with respect to a target part. High intensity light is continuously irradiated (step S13). Thereby, the detachment of the template agent from the plating layer is promoted, the template agent is efficiently removed from the plating layer, and a porous plating layer is formed. In addition, when the removal liquid tank 41 is sufficiently larger (longer) than the plating tank 31, the path of the resin film 9 does not necessarily have to be folded.

  The target portion pulled up from the removal liquid tank 41 moves to the cleaning tank 48 and is immersed in the cleaning liquid. Thereafter, a cleaning liquid such as pure water is sprayed from the cleaning spray group 481 toward the surface of the target part, and the cleaning liquid on the surface of the target part is removed by the air from the air knife 482 (step S14). This prevents the removal liquid 411 used for removing the template agent from remaining on the resin film 9 and affecting the subsequent steps. The target portion after washing passes through the drying furnace 49, and the target portion is dried, thereby preventing drying unevenness and the like from occurring on the plating layer (porous layer) (step S15).

  The target portion where the porous layer is formed is transported to another device (of course, it may be wound up once), and the dye is adsorbed again to the porous plating layer, and then the resin film 9 is cut. Then, the substrate having the counter electrode conductive layer is provided to face each other through the spacer. And an electrolyte solution is inject | poured between a rectangular resin film and a board | substrate of a counter electrode, and a dye-sensitized solar cell is manufactured by forming a charge transport layer. When the charge transport layer is solid, a substrate having a charge transport layer and a counter electrode conductive layer may be laminated without cutting the resin film 9.

Next, experimental results showing that the removal efficiency of the template agent is improved by irradiating the plating layer in the removal liquid with light will be described. Here, a plating solution containing 5 mmol (mM) of zinc chloride per liter, 0.1 mol (M) of potassium chloride, and 40 μmol (μM) of eosin Y, which is a template agent, was prepared. For this reason, a plating layer made of a zinc oxide film containing eosin Y was formed on a substrate having an area of one main surface of 1 square centimeter (cm ² ). In addition, a small removal liquid tank for storing the removal liquid is installed in the draft chamber, and a light irradiation unit similar to that of the above-described removal device 4 is arranged, and the light irradiation unit is removed without irradiating light. The substrate after being immersed in the liquid for 24 hours is sample 1, the substrate after being immersed in the removal liquid for 8 hours while irradiating light from the light irradiation part is sample 2, and the substrate that is not immersed in the removal liquid (light irradiation part The sample 3 was prepared as sample 3. Then, Sample 1, Sample 2 and Sample 3 were washed with pure water and dried by spraying nitrogen, and then the absorbance of Sample 1, Sample 2 and Sample 3 was measured.

  Note that the absorption wavelength of zinc oxide is around 367 nanometers (nm) (exactly, the absorption wavelength of single crystal zinc oxide is 367 nm. Actually, the wavelength depends on the strain of the crystal lattice and the presence of different atoms. The absorption wavelength of eosin Y is around 530 nm, and the plating layer (zinc oxide film containing eosin Y) formed using the above plating solution is tinged with red. ing.

  Table 1 shows the measurement results of the absorbance of sample 1, sample 2 and sample 3 having a wavelength of 530 nm. In Table 1, Sample 1, Sample 2, and Sample 3 are shown by indicating 1, 2, and 3 in each column of the column labeled “Sample” at the top.

  Here, according to Lambert-Beer's law, in a layer containing a specific substance, the absorbance of the specific substance is ABS, the extinction coefficient of the specific substance is ε, the concentration of the specific substance in the layer is C, and the optical path length (in the layer When (thickness) is L, (ABS = εCL) is satisfied. In sample 1, sample 2, and sample 3, since the specific substance is eosin Y, the extinction coefficient ε is the same, and the optical path length L is also the same because the layer containing the specific substance is a plating layer having the same thickness. Therefore, in sample 1, sample 2 and sample 3, it is considered that the ratio of absorbance ABS directly indicates the concentration ratio of eosin Y (adsorption amount ratio) in the plating layer. Therefore, in Table 1, the removal rate of eosin Y in sample 1 or sample 2 is obtained by dividing the absorbance of sample 3 by the absorbance of sample 1 or sample 2 by the absorbance of sample 3.

  As shown in Table 1, the removal rate in sample 2 is about 2.7 times the removal rate in sample 1. Actually, since the immersion time of sample 2 in the removal liquid is one third of that of sample 1, when eosin Y is removed from the plating layer by immersing the substrate on which the plating layer is formed in the removal liquid. By irradiating the plating layer with light from the light irradiating part, it can be understood that the removal efficiency becomes 8 times or more compared with the case where light irradiation is not performed.

  By the way, in the above experiment, the illumination light provided in the draft chamber was accurately irradiated even in the sample 1 immersed in the removal liquid for 24 hours without irradiating light from the light irradiation unit. (In fact, it was irradiated for only 8 hours.) Therefore, the difference between the intensity of light from the illumination light source on the substrate and the intensity of light from the light irradiation unit on the substrate will be examined.

  In the above experiment, the distance between the light source for illumination (here, the fluorescent lamp) and the substrate is 1.2 meters (m), and the total luminous flux from the light source for illumination is 2900 lumens (lm). ). On the other hand, the distance between the light irradiation unit and the substrate is 0.4 m, and the total luminous flux from the light irradiation unit is 14000 lumens. Here, the lumen, which is a unit of light flux, is defined as “light flux emitted from a point light source having a uniform luminous intensity of 1 candela (cd) within a solid angle of 1 steradian (sr)”. Since the ratio between the intensity of the emitted light and the intensity of the light emitted from the illumination light source is obtained as the ratio of the total luminous flux, the intensity of the light emitted from the light irradiation unit is the light emitted from the illumination light source 4.83 times (= 14000/2900).

In addition, the intensity of light from the light irradiation unit or the light source for illumination on the substrate is inversely proportional to the square of the distance between the light irradiation unit or the light source for illumination and the substrate. When the intensity of the light emitted from the light source is the same, the intensity of the light from the light irradiation unit on the substrate is 9.0 times the intensity of the light from the illumination light source on the substrate (= (1 /0.4 ² ) / (1 / 1.2 ² )). As described above, since the intensity of the actual light emitted from the light irradiation unit is 4.83 times the intensity of the light emitted from the illumination light source, the intensity of the light from the light irradiation unit on the substrate is This is 43.5 times (= 4.83 × 9.0) the intensity of light from the illumination light source on the substrate.

  Actually, even when the light irradiation unit is arranged at a position 0.8 meters away from the substrate (that is, twice the distance), the intensity of the light from the light irradiation unit on the substrate is from the light source for illumination. About 11 times the intensity of light on the substrate, the removal of the template agent from the plating layer is sufficiently accelerated, and the light irradiation part is placed at a position 1.2 meters away from the substrate (that is, three times the above distance). Even if it does, the intensity | strength on the board | substrate of the light from a light irradiation part will be about 5 times the intensity | strength on the board | substrate of the light from the light source for illumination, and removal of the template agent from a plating layer is accelerated to some extent. Further, even when a fluorescent lamp is used as a light irradiation unit and disposed at a position of 0.4 m from the substrate, the intensity of light from the fluorescent lamp on the substrate is 9 of the intensity of light from the illumination light source on the substrate. The doubling facilitates the removal of the template agent from the plating layer.

  As described above, the resin film 9 is irradiated with high-intensity light from the light irradiation unit 42 provided in the vicinity of the resin film 9 in the removal liquid 411 while the resin film 9 is immersed in the removal liquid 411. It is possible to remove the template agent from the plating layer on the film 9 very efficiently (in a short time). Further, in the plating system 1, the resin film 9 is continuously conveyed from the plating layer forming unit 3 to the removing device 4, thereby improving the throughput related to the formation of the porous layer and the quality of the porous layer. be able to.

  By the way, light of a wide range of wavelengths from ultraviolet light to visible light is emitted from the light irradiation unit 42 of the removal device 4 in FIG. 2, and the light from the light irradiation unit 42 is included in the absorption wavelength band of the template agent. By including light of a wavelength, the template agent in the plating layer of the resin film 9 immersed in the removing liquid 411 is activated. Since the template agent is more stable in the state of being present in the removal liquid 411 than in the state of being adsorbed in the zinc oxide film, the activation of the template agent results in more detachment of the template agent from the plating layer. Will be promoted. That is, the template agent can be more efficiently removed from the plating layer because the light from the light irradiation unit 42 includes light having a wavelength included in the absorption wavelength band of the template agent.

  Further, when the light from the light irradiation part 42 includes light having a wavelength included in the absorption wavelength band of the zinc oxide film which is the main body of the plating layer, electrons in the zinc oxide film are excited and electrons are supplied to the template agent. Is done. Thereby, the template agent is ionized and easily dissolved in the removal liquid 411 in a short time, and the template agent can be more efficiently removed from the plating layer.

  Furthermore, since the light from the light irradiation part 42 contains ultraviolet rays (light having a wavelength of 10 to 400 nanometers (nm)), the template agent which is a high molecular weight organic substance is decomposed to be reduced in molecular weight and removed from the plating layer. The separation can be promoted, that is, the organic template agent can be more efficiently removed from the plating layer.

  FIG. 4 is a diagram illustrating another example of the removing device. In the removing device 4 a shown in FIG. 4, a removing liquid regeneration unit 435 is provided instead of the drainage tank 434 of the removing device 4 in FIG. 2, and the removing liquid regeneration unit 435 is connected to the removing solution tank 433. The other structure is the same as that of the removal apparatus 4 of FIG.

  The removal liquid regeneration unit 435 includes a removal liquid 411 discharged from the removal liquid tank 41 via the circulation channel 43 (a removal liquid 411 containing a template agent removed from the plating layer, hereinafter referred to as “discharge removal liquid”). And the template agent in the discharge / removal solution is adsorbed to the activated carbon filter provided inside, thereby removing the template agent from the discharge / removal solution. Removal of the template agent from the discharge removal liquid is realized by decomposing the template agent in the discharge removal liquid by irradiating the discharge removal liquid with ultraviolet rays and / or photocatalysis of titanium oxide provided inside. May be. The discharged and removed liquid from which the template agent has been removed is stored in the removed liquid tank 433 and used for replenishment or replacement of the removed liquid 411 in the removed liquid tank 41.

By the way, in manufacturing a dye-sensitized solar cell, a large amount of a removing solution is used (for example, a template agent from a plating layer on a small substrate having an area of 1 cm ² of one main surface used in the above-described experiment). Even if it is only removed, at least several hundred milliliters (ml) of removing liquid is required.) The manufacturing cost of the solar cell increases, and depending on the disposal method of the removing liquid, an environmental load is generated. . On the other hand, in the removal device 4a of FIG. 4, by providing the removal liquid regeneration unit 435 that removes the template agent contained in the removal liquid 411 in the removal liquid tank 41, the manufacturing cost of the solar cell can be reduced, and the environment can be reduced. It is possible to stably remove the additive from the plating layer while reducing the load on the plating layer.

  FIG. 5 is a diagram showing another example of the plating system. In the plating system 1a of FIG. 5, the spraying part 51 which sprays the pure water (other liquid may be sufficient) toward the resin film 9 between the plating layer formation part 3 and the removal apparatus 4 is provided, In the course of transporting the resin film 9 from the plating layer forming unit 3 to the removing device 4, pure water is supplied to the plating layer.

  Here, in the plating layer formed in the present embodiment, the template agent and the main body (zinc oxide film) of the plating layer are firmly bonded by drying. Therefore, in the plating system 1a of FIG. 5, the template film is supplied by supplying pure water to the resin film 9 to prevent the plating layer from drying during the transfer of the resin film 9 from the plating layer forming unit 3 to the removing device 4. The bonding agent and the main body of the plating layer are prevented from being strongly bonded (that is, the adsorption force of the template agent to the zinc oxide film is maintained in a weak state), and the template is removed from the plating layer by the removing device 4. It is possible to remove the agent more efficiently (in a short time). As a result, the throughput related to the formation of the porous layer is improved, and the energy required for removing the template agent from the plating layer (for example, the energy consumed by the light irradiation unit 42) is reduced, thereby producing a solar cell. Cost can be reduced.

  By the way, from the viewpoint of preventing the plating layer of the resin film 9 from being dried until the immersion of the resin film 9 in the removal liquid 411 is started after the resin film 9 is taken out of the plating liquid 311, for example, pure A dedicated tank for storing water is provided, and the resin film 9 is immersed in the pure water tank until just before being immersed in the removing liquid 411 (the transport path from the plating layer forming unit 3 to the removing device 4 is in pure water). The resin film 9 may be prevented from drying. In this case, since the plating liquid 311 remaining on the resin film 9 taken out from the plating tank 31 is reliably removed in the pure water tank (it can also be regarded as washing of the resin film 9), the plating liquid 311 is used. Mixing with the removal liquid 411 prevents the removal of the template agent in the removal device 4 from being affected.

  As described above, the liquid supply unit (for example, the spray unit 51 for spraying the liquid or the tank for storing the liquid) that supplies the liquid to the resin film 9 during the transfer of the resin film 9 from the plating layer forming unit 3 to the removing device 4 ) Is provided to prevent the plating layer from being dried before the template agent is removed. In addition, drying of the resin film 9 can also be prevented by speeding up conveyance from the plating layer forming unit 3 to the removing device 4.

  FIG. 6 is a diagram showing still another example of the plating system. In the plating system 1 b of FIG. 6, an auxiliary light irradiation unit 52 that emits light similar to the light irradiation unit 42 of the removal device 4 is provided between the plating layer forming unit 3 and the removal device 4.

  In the formation process of the porous layer on the resin film 9 in the plating system 1b of FIG. 6, when the plating layer is formed on the resin film 9 in the plating layer forming unit 3 (FIG. 3: step S11), the plating layer is formed. In the course of transporting the resin film 9 from the unit 3 to the removing device 4, light is applied to the plating layer of the resin film 9 from the auxiliary light irradiation unit 52 (step S11a). Subsequently, the resin film 9 is immersed in the removal liquid 411 in the removal liquid tank 41 and the resin film 9 is irradiated with light from the light irradiation unit 42 to remove the template agent from the plating layer (steps S12 and S13). ). Thereafter, the resin film 9 is taken out from the removal liquid 411 and washed in the washing tank 48 (step S14), and the treatment for forming the porous layer is completed by drying in the drying furnace 49 (step S15). .

  As described above, in the plating system 1b of FIG. 6, immediately before the resin film 9 is immersed in the removing liquid 411 (that is, after the plating layer is formed and before being immersed in the removing liquid 411), the template agent from the plating layer is used. By irradiating the resin film 9 with light that promotes the removal of the resin, the resin film 9 can be immersed in the removal liquid 411 in a state where the template agent is easily detached from the plating layer. Thereby, detachment | desorption of the template agent in a plating layer is started immediately after immersing the resin film 9 in the removal liquid 411, and a template agent can be more efficiently removed from a plating layer. As a result, the porous layer can be formed in a short time (throughput can be improved).

  In addition, also in the auxiliary light irradiation part 52, when the emitted light contains ultraviolet rays, the organic matter in the plating layer is decomposed before immersion, and the removal of the organic material from the plating layer is promoted. In addition, the light from the auxiliary light irradiation unit 52 includes the light having the absorption wavelength of the template agent, or the light having the absorption wavelength of the main body of the plating layer, thereby activating the template agent or the main body of the plating layer before immersion. It is possible to more efficiently remove the template agent from the plating layer.

  Next, a plating system using a glass substrate as an object to be processed will be described. FIG. 7 is a diagram illustrating another example of the plating layer forming unit. The plating layer forming unit 3a in FIG. 7 is a sheet-type device, and a transparent glass substrate 9a having a transparent conductive layer is an object to be processed.

  7 includes a plating tank 31a for storing a plating solution 311, a glass substrate 9a, a substrate holding unit 35 immersed in the plating solution 311, and a glass substrate held by the substrate holding unit 35. A rotating mechanism 36 that rotates the substrate holding portion 35 about a central axis that passes through the center of the main surface 9a and that is perpendicular to the main surface; the counter electrode 32 and the reference electrode 33 that are disposed in the plating solution 311; and the transparent glass substrate 9a. A power supply unit 34 for applying a potential to each of the conductive layer, the counter electrode 32 and the reference electrode 33 is provided.

  The plating tank 31 a is provided with a supply pipe 371, and the supply pipe 371 is provided with a filter 374. The supply pipe 371 is connected to the plating solution tank 373 via the pump 372. The plating solution tank 373 stores the plating solution returned from the plating tank 31a through the discharge pipe 375. By driving the pump 372, the filter 374 removes unnecessary materials and bubbles in the plating solution. A plating solution is supplied from the plating solution tank 373 into the plating tank 31a, and a certain amount of the plating solution 311 is stored in the plating tank 31a. Actually, the plating solution 311 from the supply pipe 371 is sprayed toward the main surface (the main surface opposite to the substrate holding portion 35) of the glass substrate 9a arranged in the plating tank 31a. A jet of the plating solution 311 collides with the main surface. In the plating layer forming unit 3a of FIG. 7, a circulation mechanism for circulating the plating solution 311 between the plating tank 31a and the plating solution tank 373 is constructed by the supply pipe 371, the pump 372, and the discharge pipe 375.

  A dissolved oxygen meter 313 for measuring the oxygen concentration in the plating solution 311 and a thermometer 314 for measuring the temperature of the plating solution 311 are attached to the plating tank 31a. A heater 315 a is provided in the plating solution tank 373, and the temperature controller 316 controls the heater 315 a based on the output of the thermometer 314, whereby plating that circulates between the plating tank 31 a and the plating solution tank 373. Liquid 311 is kept at a constant temperature.

  In the supply pipe 371, a gas dissolving unit 376 is provided between the filter 374 and the pump 372, and oxygen is dissolved in the plating solution 311 according to the measured value of the dissolved oxygen meter 313. An analysis device 377 for analyzing the components of the plating solution 311 is connected between the filter 374 and the gas dissolving unit 376, and the component adjustment unit 378 supplies the plating solution tank 373 according to the result of the analysis device 377. Each component (for example, high-concentration zinc chloride solution or template agent) contained in the plating solution 311 is supplied in a necessary amount. In addition, the result in the analyzer 377 can be displayed on the display unit included in the control unit 10 (see FIG. 1).

  When the porous layer is formed on the glass substrate 9a, first, the substrate holding part 35 for holding the glass substrate 9a is immersed in the plating solution 311 in the plating layer forming part 3a of FIG. The holding part 35 rotates. Further, in the power supply unit 34, a predetermined reference potential is applied to the reference electrode 33, a potential that gives a difference from the reference potential to a predetermined value is applied to the counter electrode 32, and the reference is also applied to the transparent conductive layer of the glass substrate 9a. A potential at which the difference from the potential is a predetermined value is applied. As a result, electrolytic plating is performed on the glass substrate 9a (electrodeposition is performed), and a high-quality (or high-purity) plating layer containing zinc oxide and a template agent is formed on the glass substrate 9a (see FIG. 3: Step S11).

  Actually, in the plating layer forming portion 3a, the rotation mechanism 36 is supported by a support arm (not shown), and the rotation mechanism 36 is swung in the horizontal direction, the vertical direction, or the direction perpendicular to the paper surface in FIG. After the formation of the plating layer, the support arm moves up the rotation mechanism 36, so that the glass substrate 9a can be taken out. If necessary, a mechanism for stirring the plating solution 311 may be provided in the plating tank 31a, and further, a mechanism for removing the gas dissolved in the plating solution is provided in the supply pipe 371. In cooperation, the oxygen concentration in the plating solution 311 may be increased.

  The glass substrate 9a on which the plating layer is formed is conveyed to the removing device 4b shown in FIG. In the removal device 4b for the glass substrate 9a, the removal liquid tank 41 is formed of a light-transmitting member, and the light irradiation unit 42 is provided to face one side surface of the removal liquid tank 41. Then, a substrate cassette 91 that supports the plurality of glass substrates 9a in parallel and upright is immersed in the removing liquid 411, and light from the light irradiation unit 42 facing the main surface of the glass substrate 9a is irradiated to the plating layer. By doing so, it is realized that the template agent is efficiently removed from the plating layers of the plurality of glass substrates 9a (steps S12 and S13). Then, the plurality of glass substrates 9a are taken out from the removal liquid 411 together with the substrate cassette 91 to wash the plurality of glass substrates 9a, and then the glass substrate 9a is dried (steps S14 and S15). As described above, in the plating system for the glass substrate 9a, it is possible to efficiently form the porous layer on the glass substrate 9a.

  In the removing device 4b of FIG. 8 in which the plurality of glass substrates 9a are immersed in a stationary state, the concentration of the removed template agent in the removing solution 411 in the removing solution tank 41 is in the vicinity of a part of the plating layer. There may be a local increase, the template agent concentration difference with the removal liquid 411 in the portion of the plating layer becomes lower, the amount of detachment of the template agent decreases, and the uniformity of the removal of the template agent in the entire plating layer May fall. Therefore, in such a case, it is preferable to provide a mechanism for stirring the removal liquid 411 in the removal liquid tank 41. Further, depending on the design of the removal device, the removal liquid 411 in the removal liquid tank 41 may be stirred by the flow of the removal liquid 411 ejected from the circulation flow path 43 (see FIG. 2).

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.

  In the above embodiment, the template agent is removed from the plating layer by immersing the resin film 9 or the glass substrate 9a (hereinafter collectively referred to as “object”) in the removing liquid 411. FIG. As shown, the removing device 4c may be provided with a discharge portion 41a that continuously applies the removing liquid to the plating layer of the object (in FIG. 9, the glass substrate 9a). In this case, in the porous layer forming process of FIG. 3, in step S12, continuous application of the removal liquid from the discharge portion 41a to the object is started, and in parallel with the application of the removal liquid, in step S13. Light is applied to the plating layer from the light irradiation unit 42, and the template agent is efficiently removed from the plating layer to which the removal liquid is applied from the discharge unit 41a.

  As described above, in order to efficiently remove the template agent from the plating layer, the light irradiation unit 42 that irradiates the object with light that promotes the removal of the template agent from the plating layer in the removing devices 4, 4 a to 4 c. It is important that the removal liquid tank 41 for storing the removal liquid in which the object is immersed or the discharge part 41a for continuously applying the removal liquid to the plating layer of the object is provided as the removal liquid application part. It becomes.

  In the plating system for processing the resin film 9, the plating layer of the resin film 9 is formed after the resin film 9 is taken out from the plating solution 311 until the resin film 9 is immersed in the removal solution 411. When the drying does not affect the removal of the template agent from the plating layer, a drying furnace 54 for drying the resin film 9 is provided between the plating layer forming unit 3 and the removing device 4 as shown in FIG. The plating layer on the resin film 9 may be dried. In this case, it is possible to prevent unnecessary liquid from being mixed with the removal liquid 411. In the plating system 1c of FIG. 10, the cleaning unit 53 including the cleaning tank 531, the cleaning spray group 532, and the air knife 533 is provided between the plating layer forming unit 3 and the drying furnace 54, and the plating layer is formed. The resin film 9 immediately after the cleaning is performed, and the plating solution 311 is reliably prevented from being mixed with the removal solution 411.

  When the glass substrate 9a is a processing target, depending on the type of plating layer formed in the plating layer forming part (as will be described later, a plating layer containing an additive other than the template agent, etc.), the plating system may include a chamber. And a plating layer after removal of the additive may be fired. Depending on the plating layer, for example, water as a solvent may be taken into the crystal, such as crystal water, but it is possible to remove the water in the plating layer by firing. Further, depending on the type of the substrate on which the plated layer is formed, the substrate may be prevented from being oxidized by performing baking while maintaining the inside of the chamber in a predetermined gas atmosphere (the same applies to the drying furnace 54 in FIG. 10). ).

  In the above embodiment, the template agent in the zinc oxide film, which is a plating layer, is removed, but the plating layer formed on the object may be a film other than zinc oxide, and matches the film. The type of plating solution is also changed. In addition, even when a plating layer containing a template agent or a plating layer that does not contain a template agent is formed on an object, the plating solution used for forming the plating layer is usually the main body of the plating layer. In addition to the components to be formed, an additive (additive other than the template agent) that enables adjustment of the quality of the plating layer, etc. is included. Sometimes removal of the additive is required. Even in such a case, in the removal devices 4 and 4a to 4c which are additive removal devices, the object is immersed in the removal liquid 411 or applied in parallel to the application of the removal liquid from the discharge unit 41a to the object. Thus, it is possible to efficiently remove the additive from the plating layer by irradiating the plating layer with light that promotes the removal of the additive from the plating layer.

  In addition to the resin film 9 and the glass substrate 9a, the object to be processed in the plating system may be a semiconductor substrate, a printed wiring board, or various forms other than the substrate.

  Although the invention has been illustrated and described in detail, the foregoing description is illustrative and not restrictive. Therefore, it will be understood that many variations and embodiments are possible without departing from the scope of the invention.

Claims (16)

An additive removal method for removing the additive from a plating layer on the object formed by immersing the object (9, 9a) in a plating solution (311) containing the additive,
a) a step (S12) of immersing the object in a removal liquid (411) stored in a removal liquid tank (41) or continuously applying a removal liquid to the plating layer of the object;
b) irradiating the object with light that promotes the removal of the additive from the plating layer in parallel with the step a) (S13);
Is provided. The additive removal method according to claim 1,
The light includes light having a wavelength included in the absorption wavelength band of the additive. An additive removal method according to claim 1 or 2,
The light includes light having a wavelength included in the absorption wavelength band of the plating layer. An additive removal method according to any one of claims 1 to 3,
The light includes ultraviolet rays. An additive removing method according to any one of claims 1 to 4,
After the object is taken out of the plating solution, the plating layer of the object is prevented from being dried until the step a) is started. An additive removing method according to any one of claims 1 to 5,
Immediately before the step a), the method further includes a step (S11a) of irradiating the object with light that promotes the removal of the additive from the plating layer. An additive removal method according to any one of claims 1 to 6,
The additive is a template agent. Additive removal device (4, 4a to 4c) for removing the additive from the plating layer on the object formed by immersing the object (9, 9a) in a plating solution (311) containing the additive Because
A removal liquid tank (41) for storing a removal liquid (411) in which the object is immersed, or a discharge liquid application (41a) that continuously applies the removal liquid to the plating layer of the object. And
Light irradiation unit (42) for irradiating the object in the removal liquid tank or the object to which the removal liquid is applied from the discharge unit with light that promotes the removal of the additive from the plating layer When,
Is provided. An additive removal apparatus according to claim 8, comprising:
The light from the light irradiation unit includes light having a wavelength included in the absorption wavelength band of the additive. An additive removal apparatus according to claim 8 or 9, wherein
The light from the light irradiation unit includes light having a wavelength included in the absorption wavelength band of the plating layer. An additive removing apparatus according to any one of claims 8 to 10,
The light from the light irradiation unit includes ultraviolet rays. An additive removing apparatus according to any one of claims 8 to 11,
A removal liquid regenerating part (435) for removing the additive contained in the removal liquid in the removal liquid tank which is the removal liquid application part is further provided. An additive removal apparatus according to any one of claims 8 to 12,
The additive is a template agent. A plating system (1, 1a to 1c) for forming a plating layer on an object (9, 9a),
A plating layer forming part (3, 3a) for forming a plating layer on the object by immersing the object in a plating solution (311) containing an additive;
The additive removing device (4, 4a to 4c) according to any one of claims 8 to 13, which removes the additive from the plating layer of the object,
Is provided. A plating system according to claim 14, wherein
A liquid supply unit (51) is further provided for supplying liquid to the object to prevent the plating layer from being dried during the conveyance of the object from the plating layer forming unit to the additive removing device. A plating system according to claim 14 or 15,
Another light irradiation unit (52) that irradiates the object with light that promotes the removal of the additive from the plating layer during the transportation of the object from the plating layer forming unit to the additive removing device. ).

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