JP5743591B2 - Method for forming thin film, apparatus for forming the same, method for manufacturing dye-sensitized solar cell, and apparatus for manufacturing the same - Google Patents

Description

  The present invention relates to a method for forming a thin film using a spray pyrolysis thin film deposition method (hereinafter referred to as SPD), a device for forming the thin film, and a dye-sensitized solar cell using the method for forming the thin film. The present invention relates to a manufacturing method and a manufacturing apparatus thereof. More specifically, it is possible to form a thin film with a uniform thickness, even when mass-produced, to a uniform thickness, and to produce a dye-sensitized solar cell with stable quality and at low cost by automation. The present invention relates to a method and apparatus for forming a thin film that can be produced, and a method and apparatus for producing a dye-sensitized solar cell.

Conventionally, a thin film such as a transparent conductive film made of FTO (fluorine-doped tin oxide) or the like, or a photoelectric conversion layer made of TiO ₂ or the like of a dye-sensitized solar cell is, for example, a pedestal including a heater 102 as shown in FIG. A sprayer 104 is placed facing a substrate 103 made of glass or the like placed on 101, and a solute 105 such as dibutyltin diacetate dissolved in a volatile solvent such as ethanol is used as a carrier gas. 106 and sprayed from the sprayer 104 toward the lower substrate 103 and formed on the surface of the substrate 103 by evaporation of the solvent and thermal decomposition reaction of the solute, that is, by the SPD method (see, for example, Patent Document 1).

  In this case, if the thin film material sprayed from the sprayer 104 adheres to the substrate 103, the substrate temperature is lowered, and if spraying is continued in a state where the temperature of the substrate 103 is lowered, the evaporation of the solvent and the progress of the pyrolysis reaction of the solute are hindered. Therefore, a uniform film cannot be formed. Therefore, it is necessary to spray only within a certain temperature range (for example, 450-550 degreeC), and spraying is performed intermittently. Further, since it is necessary to form a thin film with a uniform composition and a uniform thickness within the operation region of the substrate, the gantry 101 on which the sprayer 104 and / or the substrate 103 is placed is controlled by the control unit 107. The spraying is performed by relatively rotating or translating in the xy plane (see Patent Document 1).

JP 2007-144297 A

  As described above, when a thin film material is formed by spraying a thin film material with a conventional sprayer, the substrate must be inserted and removed from the apparatus provided with the sprayer one by one. There is a problem that it is very inefficient and is not suitable for mass production. Also, if spraying is not performed intermittently, the temperature of the substrate is lowered and a uniform film cannot be formed. However, if spraying is performed intermittently, when spraying starts and spraying ends, the spray state However, unlike the spraying state in which normal continuous spraying is performed, there are spray ports on the substrate, and when spraying and stopping are repeated on the substrate, the variation in film thickness due to irregular spraying becomes even greater. Therefore, it is not preferable for forming a uniform film. Further, even if the gantry and the sprayer are moved relative to each other, the moving direction is limited, and the relationship between the intermittent spraying and the moving direction cannot be completely matched between the substrates. There is also a problem that a thin film having a stable quality cannot be formed from the viewpoint of the property and uniformity of each substrate when many sheets are formed.

  Furthermore, when mass-producing dye-sensitized solar cells using such a thin film, the method of forming such a thin film is to install a substrate in the sprayer as described above, and to connect the substrate and the spray port. The method of spraying them facing each other and taking them out after film formation has a problem that it takes time to form a thin film on a single substrate and is difficult to automate.

  The present invention has been made in view of such circumstances, and in the case of forming a thin film by a spray method, a method for forming a thin film that can form a uniform film and can be automated, and the formation thereof. An object is to provide an apparatus.

  Another object of the present invention is to form a thin film such as a transparent electrode film or an oxide semiconductor film for a photoelectric conversion layer with a uniform composition and a uniform film thickness, and from the thin film formation to the final finish. It is an object of the present invention to provide a method for producing a dye-sensitized solar cell that can be automated by a conveyor system and an apparatus for producing the same.

  In the thin film forming method of the present invention, a substrate is placed on the surface of a cart capable of heating the substrate placed on the surface, and the plurality of carts are continuously placed in a first direction while the substrate is heated. The cart is intermittently moved, and when the cart moves, the thin film material is sprayed on the surface of the substrate when the cart moves by a sprayer disposed between two adjacent carts. Is stopped two or more times to stop spraying the thin film material, and then the cart is moved in the second direction in which the direction of movement of the cart is changed without changing the direction of the cart. When the cart moves, the thin film material, which is the same as the thin film material, is sprayed on the surface of the substrate by the sprayer that is intermittently moved and disposed above the two adjacent carts when the cart is stopped. Cart is stopped Time and repeating the stop and spray to stop spraying of the thin film material more than once.

  Here, the “cart” means a box-shaped substrate mounting table that can move on a rail or the like while mounting a substrate.

  The thin film forming apparatus of the present invention is capable of heating a substrate placed on the surface, and a plurality of carts provided so as to be intermittently movable by collecting a plurality of rows arranged in a row, and the plurality of the plurality of carts A first moving means for moving the cart by one pitch in the first direction; and a sprayer provided above between two adjacent carts when the plurality of carts arranged along the first direction are stopped. And a second moving means for moving the cart facing the first direction in a second direction different from the first direction while maintaining the orientation of the cart as it is.

  Here, “1 pitch” means the distance between the same parts of two carts arranged in succession, that is, the length of one cart including a spacer as shown by p in FIG. means.

Furthermore, preparation of the dye-sensitized solar cell according to the present invention, (a) forming a transparent conductive film on the surface of the transparency substrate, an oxide for a photoelectric conversion layer in a predetermined region of the surface of the pre-SL transparent substrate semiconductor to form a layer, the collector wire is formed by applying a metal paste to the gap of the oxide semiconductor layer, before Symbol dye was adsorbed to the oxide semiconductor layer, applying a sealant along the current wire forming a working electrode by, a counter electrode by forming a metal layer having a catalytic in a predetermined area of the (b) metals and corrosion and conductive layer is formed on the surface of the substrate, before Symbol metal substrate surface And (c) an assembly step of bonding the working electrode and the counter electrode to cure the sealing agent and then injecting an electrolyte material, and at least forming the transparent conductive film. It is formed in a way And features.

  Here, “transparent” means translucency that transmits light, and does not mean that it is completely transparent.

  The step of forming a transparent conductive film on the surface of the transparent substrate is performed by changing the moving direction of the cart without changing the direction of the cart on which the transparent substrate is placed, and spraying the transparent conductive film material on the transparent recording plate. The transparent conductive film can be formed in a narrow area by performing from a different direction, and performing the movement of the cart so that the cart after spraying returns to the original position. Since the transparent substrate returns to the original position, it can be automatically transferred to the next step.

  According to the thin film forming method of the present invention, the cart on which the substrate is placed is moved at a predetermined pitch, and is intermittently moved for a certain period of time, and is provided above two adjacent carts when stopped. Since the sprayer sprays only when the cart is moving, even if spraying by the sprayer is performed intermittently, there is no substrate under the sprayer that causes instability of spraying at the start and end of the spraying It can be performed in a state, and the uniformity of spraying by spraying is not impaired. In addition, the substrate is constantly heated by the cart, and the temperature drop due to spraying (spraying) of the thin film material is restored when the cart is stopped, and the thin film material sprayed at the stop is thermally decomposed to form a desired thin film. can do. Furthermore, in the present invention, since only the moving direction is changed to the second direction without changing the direction of the cart and the same intermittent movement is performed and spraying (spraying) is similarly performed by the sprayer, the substrate is differently directed from different directions. Since spraying is performed, the uniformity of the thin film can be further ensured.

  For example, in the case of a rectangular substrate, by making the cart move in a rectangular shape, spraying can be performed from the direction along all sides of the substrate, and a very uniform thin film can be formed. If the spraying is performed twice or more in this one direction, a thin film can be formed many times with a solution having a low concentration, and a thin film having a very stable thickness and components can be formed. be able to. In addition, according to the present invention, since a uniform process of spraying, stopping spraying for a certain period of time, performing thermal decomposition, and repeating spraying and stopping again, thin film formation can be performed automatically. However, a thin film having a very stable film thickness can be formed.

  Further, according to the thin film forming apparatus of the present invention, the cart can be moved by a fixed distance at a constant speed only by operating a moving means comprising a simple pushing mechanism such as a pusher. Therefore, it is possible to form a uniform film simply by pushing and moving the cart, and since the mechanism is simple, it can be easily automated and can form a thin film with a constant film thickness at a low cost. it can.

It is a plane explanatory view showing one embodiment of the thin film formation device by the present invention. It is a longitudinal cross-sectional explanatory drawing of the sprayer part of FIG. It is the figure which showed the other form of the cart movement of FIG. 1 with the perspective explanatory drawing. It is plane explanatory drawing which shows one Embodiment of the manufacturing apparatus of the dye-sensitized solar cell by this invention. FIG. 5 is a conceptual diagram when a substrate is loaded or unloaded in the configuration of FIG. 4. FIG. 5 is a conceptual explanatory diagram of an apparatus for applying a metal paste or the like with the configuration of FIG. 4. It is plane explanatory drawing which removed the counter pole of an example of the dye-sensitized solar cell manufactured by this invention, and the cross-sectional explanatory drawing of the state which provided the counter pole in the BB line cross section. It is explanatory drawing which shows an example of the thin film formation method by the conventional spray method.

  Next, a thin film forming method, a thin film forming apparatus, a dye-sensitized solar cell manufacturing method and a manufacturing apparatus thereof according to the present invention will be described with reference to the drawings.

  The thin film forming method and forming apparatus according to the present invention includes a surface of a cart 41 that can heat a substrate 31 placed on the surface as shown in FIG. The substrate 31 is placed on the substrate 31, and the substrate 31 is heated and intermittently moved in the first direction X1 by a first moving means (for example, a first pusher) 43. At this time, the sprayer 42 is disposed between the two carts 41 adjacent to each other when the cart 41 is stopped (the state shown in FIG. 1), and the cart 41 moves (for example, in FIG. 1). When the cart 41 moves from the state A to the state B), the sprayer 42 sprays the thin film material onto the surface of the substrate 31. When the cart 41 is stopped, spraying of the thin film material is stopped. Spraying and stopping by the sprayer 42 are repeated twice or more (six times in the example shown in FIG. 1: there are six sprayers 42 in the X1 direction). Thereafter, the cart 41 is intermittently moved in the second direction X2 by changing the moving direction of the cart 41 without changing the direction of the cart 41. That is, when the cart 41 comes to the top position in FIG. 1, the cart 41 is moved in the X2 direction by moving the cart 41 in the same manner by the second moving means (second pusher). Also in this second direction, as in the case of the first direction X1, the sprayer 42 is disposed between the two adjacent carts 41 when the cart 41 is stopped, and the sprayer 42 causes the cart 41 to move. When moving, the same thin film material as that described above is sprayed on the surface of the substrate 31, and spraying and stopping by the sprayer 42 are repeated twice or more.

  More specifically, first, the substrate 31 is loaded onto the empty cart 41 by the loading / unloading means 47, and the substrate 31 is placed in the groove on the surface of the cart 41. Each cart 41 is provided with a spacer 41a on its side surface, and each cart 41 is in contact with the cart 41 via the spacer 41a at a constant interval. The cart 41 moves. In the example shown in FIG. 1, first to fourth moving means 43 to 46 are provided on a rectangular work table 46 so that the moving direction of the cart 41 changes by 90 ° along each side of the square. ing. Therefore, the substrate 31 placed by the loading means 47 first moves along the first direction X1, and the thin film material is sprayed from the sprayer 42 onto the surface of the substrate 31 while the cart 41 is moving. When the pitch, that is, the cart 41 is moved by one, the spraying by the sprayer 42 is stopped, and the substrate temperature is maintained at a predetermined temperature for thermal decomposition or the like. By starting and ending spraying (spraying) by the sprayer 42 when the cart 41 is stopped, spraying is started, and after stopping, the amount of spray at the beginning and end of spraying is set. The unstable spray can be prevented from being applied to the substrate surface. In the initial moving direction in which the substrate 31 is loaded, it is preferable that the sprayer 42 is not attached and spraying is not performed at the time of both movement and stop, so that the preheating region is set.

  Such spraying (spraying) and thermal decomposition by the sprayer 42 are repeated (in the example shown in FIG. 1, six sprayers 42 are provided in the X1 direction, and spraying and thermal decomposition are repeated six times. The thermal decomposition while performing the movement is performed for about 2 seconds on the 150 mm square substrate and stopped for about 18 seconds, and one spraying and one cycle of thermal decomposition can be performed in a total of 20 seconds. When the spraying and stopping along the direction X1 are completed, the direction of the cart 41 is not changed, and the moving direction is changed to the second direction X2 by using the second moving means 44. This second direction. In X2, similarly to the first direction, six sprayers 42 are attached, and spraying and stopping are repeated six times in the same manner, and when spraying and thermal decomposition along the second direction X2 are finished, Moving means 4 Then, only the moving direction of the cart 41 is changed again to the third direction X3, and the same spraying and pyrolysis are repeated alternately, and then the fourth moving means 46 again sets the moving direction of the cart 41 again. 90 degrees and the same spraying and thermal decomposition are repeated, and the movement of the substrate 31 placed by the loading means 47 is in this order in the first direction X1 and the second direction X2. When the cart 41 is moved, when the cart 41 that is actually arranged continuously is moved, after the cart 41 is moved by one in the first direction X1, the fourth moving means 46 lowers the cart 41 in FIG. The cart 41 in the side row is moved along the fourth direction X4, and then the carts 41 arranged in the right column in FIG. 1 are moved along the third direction X3 by the third moving means 45, Then the top row of figure 1 By moving the row of carts 41 in the cart by one cart by the second moving means 44, all the carts 41 can be moved by one cart 41. One cart that is vacant by moving This is because it is necessary to use the space of minutes.

In FIG. 1, in order to make the movement of the cart 41 easy to understand, the plan view is shown with the cover case omitted, but FIG. 2 is a cross-sectional explanatory view of a portion of the sprayer 42, and FIG. As shown in the respective perspective views of the other embodiments, the periphery of the cart 41 is covered with a cover case 51, and a blower or the like is used so that pyrolysis gas and organic solvent gas generated during spraying can be removed inside. The exhaust pipe 52 is connected to the intake air. Note that a heater (not shown) is built in the cart 41, and the temperature of the substrate 31 placed thereon can be kept at a desired temperature, while the rail 53 attached to the work table 46 is mounted. Can be moved. The heating of the substrate 31 is set in accordance with the thin film formed on the substrate 31 and the material of the substrate 31. For example, when a transparent conductive film is formed on a transparent substrate such as glass, it is kept at about 500 ° C. and the same. When a semiconductor layer made of TiO ₂ or the like is formed on the substrate 31, the temperature is set to about 150 ° C.

For example, when the size of the substrate 31 is a 150 mm square substrate, three sprayers 42 are provided side by side at intervals of 75 mm. At this interval, for example, by setting the height of the surface of the substrate 31 and the injection port of the sprayer 42 to about 250 mm, it is possible to form a film almost uniformly in the direction in which the sprayers 42 are arranged, and in the first direction X1, By moving the substrate 31, the thin film can be formed almost uniformly with a thickness of about 200 nm by the six sprayers 42 in one direction. Furthermore, a more uniform film can be formed by arranging the sprayers 42 of the cart 41 so as to be offset from each other so as to interpolate the interval between the sprayers 42 of the adjacent carts 41. And when it goes round along 4 sides, it can form in the thickness of about 0.8-1 micrometer. This thickness can be set to a desired thickness depending on the concentration of the thin film material to be sprayed and the number of times of spraying. However, if the concentration of the solution is too high, the uniformity of the film is impaired. As a material for this thin film, for example, when forming a transparent conductive film made of fluorine-doped tin oxide (FTO), a solution of antimony fluoride dissolved in an ethanol solution of dibutyltin diacetate (DVTDA) is sprayed. It can be formed by thermal decomposition at about 500 ° C. In the case of forming TiO ₂ , a dispersion solution of titanium oxide particles in which acetic acid is added to titanium oxide nanoparticles formed by diluting titanium tetraisopropoxide with ethanol at a substrate temperature of about 150 ° C. Can be sprayed and then sintered at about 450 ° C.

  As shown in FIG. 1, the cart 41 is moved by forming a loop as a moving route, whereby the substrate 31 can be returned to the same position before and after the thin film forming step, and the operation can be easily automated. In addition, it is preferable because a series of operations can be performed in a narrow space. In particular, by moving the square substrate 31 in four directions, it can be sprayed from each direction along the four sides of the substrate 31, which is preferable from the viewpoint of the thickness of the thin film and the uniformity of the components. From this point of view, for example, when the shape of the substrate 31 is pentagonal, hexagonal, or triangular, the substrate 31 is formed by changing the moving direction to 5 directions, 6 directions, 3 directions, etc., respectively. Can be sprayed along each side, and is preferable from the viewpoint of uniformity.

  However, it is not always necessary to change the moving direction by the number of directions according to the number of sides of the substrate, and the uniformity of the thin film can be ensured by changing the spraying direction regularly. In other words, the present invention is characterized in that the sprayer 42 and the substrate 31 are not simply moved relative to each other but are completely sprayed on the substrate 31 from at least two directions. From this point of view, for example, as shown in FIG. 3, a square substrate 31 or a change in the S-shaped moving direction may be used. In FIG. 3, although partially broken, a cover case 51 is provided, and a work table 46 and a rail 53 that moves the cart 41 are also shown.

  In the above-described example, the transparent conductive film and the oxide semiconductor layer are formed. However, the present invention is not limited thereto, and the present invention is not limited thereto as long as the thin film can be formed by spraying. For example, even when an n-type layer and a p-type layer of a III-V group compound are stacked, they can be formed by the same method. According to the spraying method, a single crystal layer cannot be formed, but since it can be formed at atmospheric pressure without applying a vacuum, it can be formed very easily and inexpensively.

  Next, a method of manufacturing a dye-sensitized solar cell having a substrate size of 150 mm square and a manufacturing apparatus thereof using this thin film forming apparatus will be described with reference to FIGS.

  The example of the structure of the dye-sensitized solar cell is shown in FIG. 7 in which a counter electrode (opposite electrode substrate) 2 is removed and a plan view and a counter electrode 2 are shown when the working electrode (photoelectrode substrate) 1 is viewed from above. As shown in the cross-sectional explanatory view of the B-B state, the working electrode 1 and the counter electrode 2 are attached by a sealing agent 14 so as to face each other with a predetermined gap, and the working electrode 1 and the counter electrode 2 are Porous metal oxide such as titanium oxide in which the electrolyte material 16 is sealed in the gap, and electrons excited in the dye of the photoelectric conversion layer 15 by sunlight are semiconductors in the photoelectric conversion layer 15 It is injected into the thin film, moves through the thin film, is transmitted to the transparent conductive film 12, and further reaches the counter electrode 25 of the counter electrode 2 via the working electrode 17 and the external circuit including the load. Flows and acts as a battery.

  First, in order to form the working electrode 1, for example, vacuum suction is performed by a robot 61 that can be moved two-dimensionally from a stock holder of a transparent substrate 11 (see FIG. 7) made of soda lime glass, quartz glass, borosilicate glass, neoceram, or the like. By this method, the transparent substrate 11 is sucked and loaded onto the moving cart 41. For example, as shown in FIG. 5, this loading is performed by vacuum suction by a robot capable of two-dimensional movement to set the transparent substrate 11 in the groove of the hot plate of the cart 41. The timing of loading the transparent substrate 11 onto the cart 41 is synchronized with the timing of movement of the cart 41 at one pitch when the material of the transparent conductive film 12 described below is sprayed.

  Then, it is transferred into the SPD chamber 62 for FTO, and the transparent conductive film 12 (see FIG. 7) made of, for example, a fluorine-doped tin oxide (FTO) film is converted into diisopropyl tin diacetate with isopropyl alcohol by the above-described thin film forming method. It is formed by spraying a solution in which a predetermined amount of ammonium fluoride aqueous solution is added to the solution. At this time, the substrate temperature is controlled to be 500 ° C. ± 20 ° C. while the nozzle of the sprayer 42 is fixed, and the cart 41 is set so that the spraying direction is from the four directions of the transparent substrate 11 as described above. Change the direction to 4 directions and spray. The transparent conductive film 12 is preferably a fluorine-doped tin oxide (FTO) film having a high visible light transmittance and a low sheet resistance. However, the transparent conductive film 12 is not limited to this example, and an indium tin oxide (ITO) film or an aluminum-doped zinc oxide ( AZO) can be selected from the films including at least one of the films, and the spray solution to be sprayed can be changed depending on the film.

Next, a metal mask (not shown) is covered on the transparent conductive film 12 at the masking / unmasking stage 64 to expose only the formation place of the photoelectric conversion layer 15 (see FIG. 7), and an oxidation made of, for example, a TiO ₂ film. The physical semiconductor layer is formed in the TiO ₂ SPD chamber 63 in the same manner as the thin film forming method described above. That is, the substrate temperature is set to 150 ± 10 ° C., for example, titanium tetraisopropoxide is diluted with ethanol, and a predetermined amount of water is added thereto and heated and boiled to obtain titanium oxide nanoparticles having an average particle diameter of 7 nm. A dispersion of titanium oxide particles obtained by adding acetic acid to the obtained product was sprayed by the sprayer 42 described above. Also in this case, the thickness was formed to 10 ± 1 μm by spraying from four directions six times in each direction. The TiO ₂ film is an n-type oxide semiconductor layer that absorbs a dye and acts as an active layer of DSC. As the porous semiconductor (oxide semiconductor) film, in addition to titanium oxide (TiO ₂ ), tin oxide (SnO ₂ ), zinc oxide (ZnO), niobium oxide (Nb ₂ O ₅ ), or the like can also be used. Further, when the metal mask is put on or removed as described later, it can be carried out by a robot as shown in FIG. The timing of this masking and the next unmasking is also matched with the loading timing of the transparent substrate 11 described above.

  Next, the mask is removed by the masking / unmasking stage 64, the transparent substrate 11 is moved to the metal paste application stage 65 provided in the vicinity of the SPD chamber 63, and the current collector 13 (13a, 13b: see FIG. 7). ) Are formed with a width of 0.5 ± 0.1 mm around the photoelectric conversion layer 15 and around the transparent substrate 11. For example, as shown in FIG. 6, this silver grid line is formed by using a multi-nozzle dispenser machine in which a plurality of dispensers 54 are arranged, for example, with a silver paste having an accuracy of ± 0.1 mm at a predetermined place. Apply with. The silver grid ship is also applied in the same time, for example, 30 seconds so as to synchronize with the timing of one pitch movement of the cart 41 for forming the transparent conductive film 11. The current collector 13 reduces the resistance loss of the transparent conductive film (FTO) 12 and contributes to collecting carriers generated by light more efficiently.

Next, the substrate on which the TiO ₂ film and the silver grid lines are formed is taken out from the cart 41 and moved into the belt furnace 66 to sinter (sinter) the TiO ₂ film and the silver paste. This belt furnace 66 is a furnace whose temperature rises linearly at an inlet of about 100 ° C. and an outlet of about 520 ° C., for example, is about 13 m long and takes about 30 minutes for sintering. The thickness of the current collector 13 after sintering is 20 μm or less, the specific resistance is 0.03 Ω · cm or less, and the TiO ₂ film forms TiO ₂ —TiO ₂ and TiO ₂ —FTO by this heat treatment. The thickness becomes 10 ± 1 μm.

The transparent substrate 11 that has finished the belt furnace 66 is transferred from the cart 41 to the belt, and is naturally cooled to 100 ° C. or lower by advancing the cooling region 67 while being conveyed by the belt, and reaches the circular dye adsorption tank 68. Here, the transparent substrate 11 is transferred from the belt to the dye adsorption tank 68 by a robot (not shown) by the same device as the loading device shown in FIG. The dye adsorption tank 68 is partitioned into small chambers in which the transparent substrates 11 are stood up one by one, and are formed so as to rotate sequentially. For example, 540 small chambers are formed along the circumferential direction, and are formed so as to make one round in 3 hours. In other words, the dye adsorption is performed for 3 hours per substrate, but the dye adsorption of the three transparent substrates 11 is completed per minute, and it matches the moving time of one substrate that intermittently moves in the spray (SPD) chamber. I'm allowed. In other words, the removal of the transparent substrate 11 from the dye adsorption tank 68 and the mounting of the next transparent substrate 11 to the dye adsorption tank 68 are performed every 20 seconds. As the dye, ruthenium dyes having absorption spectra in the visible light and infrared light regions, azo dyes, quinone dyes, quinone imine dyes, cyanine dyes, merocyanine dyes, coumarin dyes, and the like can be used. A liquid obtained by dispersing these dyes in a solvent such as a 50:50 mixed solution of acetonitrile and t-butyl alcohol is filled in the dye adsorption tank 68. This dye adsorption serves to generate excited electrons in the DSC light-sensitive active layer and transfer them to the TiO ₂ film. This dye adsorption on the oxide semiconductor layer such as TiO ₂ becomes the photoelectric conversion layer 15 (see FIG. 7).

The transparent substrate 11 on which the dye is adsorbed is transported again by the belt conveyor and cleaned by the surface cleaning stage 69. These operations are also matched with the timing (20 seconds in the above example) of moving the cart 41 by one pitch. This cleaning is performed while the wiping pad is rotated by a robot, the pasting area is cleaned, and dried pigment, TiO ₂ and other impurities are removed.

  Thereafter, for example, an ultraviolet curable resin is applied on the sealant application stage 70 of the sealant 14 (see FIG. 7). As the sealant 14, an epoxy resin, an acrylic resin, a polyurethane resin, or an ionomer resin can be used in addition to the ultraviolet curable resin. Since this sealing agent 14 has not only the adhesion of both, but also the function of protecting the current collector 13 from the electrolyte material 16, so that not only the upper surface of the current collector 13 but also the side surface thereof is completely covered. It is applied along the current collector line 13. The sealing agent 14 also prevents evaporation of the electrolyte material 16 and prevents moisture, atmospheric impurities, and the electrolyte material 16 from coming into contact with the current collector 13. For the application of the ultraviolet curable resin, for example, a multi-nozzle dispenser having three nozzles as shown in FIG. 6 can be used. This operation is also matched to the timing described above.

  The formation of the working electrode (photoelectrode) 1 (see FIG. 7) is completed in the above steps. Although it is performed in parallel with the formation of the working electrode 1, the manufacturing of the counter electrode 2 will be described next.

  First, the metal substrate 21 (see FIG. 7) is loaded on the hot plate of the cart 41 using a loading / unloading device 71 as shown in FIG. Then, an injection hole 23 (see FIG. 7) for injecting the electrolyte material 16 is drilled in the metal substrate 21 by the hold-rilling device 74. Although this inlet 23 needs to be formed for each space partitioned by the above-described current collector 13, as shown in FIG. 7, when the space partitioned by the current collector 13 is connected to one, that is, If the current collector 13 is formed so that one photoelectric conversion layer 15 is continuous, even one injection port 23 can inject the electrolyte material 16 into the whole. The timing of this loading and hold reeling is also matched with the timing (20 seconds) of movement of the cart 41 at 1 pitch P (see FIG. 1).

  Thereafter, the cart 41 is moved and moved to the FTO spray chamber 72. In the FTO spray chamber 72, as described in the method for forming the transparent conductive film 11, the spraying of the FTO material by the intermittent movement of the cart 41 and the thermal decomposition are alternately repeated in one direction, and then the orientation of the cart 41 is changed. It is formed by repeating the same operation while changing only the moving direction without changing. In the example shown in FIG. 4, the spraying and pyrolysis are repeated in four directions, and the original position is restored. The conductive layer 22 in the FTO chamber can be formed in the same manner as the transparent conductive film 12 on the working electrode side, but there is no pinhole or crack, and the sheet resistance is 10Ω / □ or less. When the metal substrate 21 is used, the conductive layer 22 is less meaningful as a conductive layer, but it can prevent corrosion of the electrolyte material 16 and the material of the metal substrate 21 is not limited and is inexpensive. Can be used. As the metal substrate 21, for example, a highly conductive substrate such as chromium, copper, aluminum, nickel, tungsten, molybdenum, titanium, or zinc can be used. In addition to the FTO film, a highly corrosion resistant film such as titanium, tungsten, vanadium, or zirconium can be used as the conductive layer 22.

Next, masking 75 is performed. This masking is performed by keeping a clean state without attaching platinum or the like to the sticking region, and is performed by covering with a metal mask. That is, as before the formation of the TiO ₂ film on the photoelectrode side, the metal mask is sucked with the same apparatus as shown in FIG. Do. The metal mask is arranged with an accuracy of ± 0.1 mm.

  Then, in the platinum spray chamber 73, a platinum film is formed by spraying as an example of the metal film by the same method as the thin film forming method described above. This platinum film is used as a catalyst, and helps to efficiently move electrons from the counter electrode 25. For this reason, it is not necessary to increase the thickness, and it is preferable that the thickness is about 40 to 100 nm, and rather it is intermittent and granular, because the surface area becomes large. The platinum film is formed at a temperature of 150 ± 10 ° C. Thereafter, the mask is removed in the masking chamber 75 and sintering is performed in the belt furnace 74. This masking and mask removal are also matched to the above-mentioned timing. The belt furnace 76 is set to about 450 ° C., and performs heat treatment for about 30 minutes while moving with the belt. By this heat treatment, an island is formed on the conductive layer 22 and promotes catalyst curing. Then, when the belt furnace 76 is finished, the belt moves to advance the cooling region 77 and cool to approximately room temperature.

The counter electrode 2 (see FIG. 7) can be formed by the above process. Then, on the assembly stage 81, the working electrode 1 coated with the sealant 14 and the counter electrode 2 (see FIG. 7) are overlapped by a two-dimensional positioning robot. The overlay accuracy of both is also performed with an accuracy of ± 0.2 mm. Then, the ultraviolet irradiation time is adjusted by the actual time of monitoring the ultraviolet energy of the lamp by irradiating and curing the ultraviolet ray on the curing stage 82 of the ultraviolet curable resin. Next, the electrolyte material 16 is injected by the two-dimensional positioning robot of the electrolyte material injection stage 83. When there are a plurality of electrolyte material injection ports 23, an electrolyte material (electrolytic solution) 16 is simultaneously injected from the plurality of injection ports using an injection device having a multi-nozzle. The electrolyte material 16 has an important function of moving electrons from the counter electrode 25 to the dye molecules on the TiO ₂ film of the working electrode 1. Then, the inlet 23 is sealed with a cover glass 24 or the like, whereby the DSC module is completed (DSC module completion stage 84), and is lowered from the belt conveyor to complete the manufacturing operation. The electrolyte material 16 is obtained by dissolving lithium iodide, t-butylpyridine, dimethylpropylimidazolium iodide or methylpropylimidazolium iodide in a solvent such as acetonitrile, γ-butyrolactone, methoxypropionitrile, or propylene carbonate. Can be used.

As described above, the dye-sensitized solar cell manufacturing apparatus of the present invention includes the spray chamber 62 for the transparent conductive film (FTO) 12 for the working electrode 1 and the spray chamber 63 for the photoelectric conversion layer (TiO ₂ film) 15. In addition, a spray chamber 72 for the conductive layer (FTO) 22 for the counter electrode 2 and a spray chamber 73 for platinum (Pt) are arranged adjacent to each other, and are conveyed by belt furnaces 66 and 76. However, since it is configured to sinter, the entire manufacturing structure is laid out in a compact arrangement in which the horizontal length L1 in FIG. 4 is about 11 m and the vertical length L2 in FIG. 4 is about 17 m. We were able to. Furthermore, working time for each substrate, for example, one cycle of intermittent movement of the substrate in each spray chamber (time for one movement and stop), masking, unmasking, removal from the dye adsorption tank and insertion, By unifying all the work time per sheet, for example, 20 seconds, the progress of the photoelectrode and the counter electrode 2 can be completely synchronized. The process up to the final step of the sealing can be completely automated.

DESCRIPTION OF SYMBOLS 1 Working electrode 2 Counter electrode 11 Transparent substrate 12 Transparent electrically conductive film 13 Current collector 14 Sealing agent 15 Photoelectric conversion layer 16 Electrolyte material 17 Working electrode 21 Substrate 22 Conductive layer 23 Electrolyte material injection port 24 Cover glass 25 Counter electrode 31 Substrate 41 Cart 42 Sprayer 43-46 First to fourth moving means 51 Cover case 62, 63, 72, 73 Spray chamber 66, 76 Belt path 68 Dye adsorption tank 70 Sealing agent application stage 81 Assembly stage 82 Curing of UV curable resin Stage 83 Electrolyte material injection stage 84 DSC module completion stage

Claims (4)

Place the substrate on the surface of the cart that can heat the substrate placed on the surface,
A plurality of the carts are continuously moved in the first direction while the substrate is heated, and the sprayer is disposed above the two adjacent carts when the cart is stopped, When the cart is moved, the thin film material is sprayed on the surface of the substrate, and when the cart is stopped, spraying and stopping are repeated twice or more according to the procedure of stopping the spraying of the thin film material,
Thereafter, the cart is intermittently moved in a second direction in which the moving direction of the cart is changed without changing the direction of the cart, and the sprayer is disposed between the two adjacent carts when the cart is stopped. Thus, when the cart moves, the same thin film material as the thin film material is sprayed on the surface of the substrate, and when the cart is stopped, spraying and stopping are performed twice by the procedure of stopping spraying of the thin film material. A method for forming a thin film, which is repeated as described above. A plurality of carts that can heat a substrate placed on the surface, and are provided to be movable intermittently by collecting a plurality of rows arranged in a row,
First moving means for moving the plurality of carts by one pitch in a first direction;
A sprayer provided above two adjacent carts when the plurality of carts arranged along the first direction are stopped;
Second moving means for moving the cart facing the first direction in a second direction different from the first direction while maintaining the orientation of the cart;
An apparatus for forming a thin film, comprising: (A) forming a transparent conductive film on the surface of the transparency substrate to form an oxide semiconductor layer for a photoelectric conversion layer in a predetermined region of the surface of the pre-SL transparent substrate, the gap of the oxide semiconductor layer step to form a collecting wire, before Symbol dye was adsorbed to the oxide semiconductor layer to form a working electrode by applying a sealing agent along the collector wire by coating a metal paste,
The corrosion and conductive layer is formed in (b) Metal surface of the substrate, the step of forming the opposite electrode by forming a metal layer having a catalytic in a predetermined area in front Symbol metal substrate surface, and (c) the An assembly step of bonding the working electrode and the counter electrode to cure the sealant and then injecting an electrolyte material;
A method for producing a dye-sensitized solar cell, wherein at least the transparent conductive film is formed by the method of claim 1 . Wherein the step of forming a transparent conductive film on the surface of the transparent substrate, said transparent substrate to form a moving loop of the cart placing the cart after spraying is carried out to return to the original position according to claim 3, wherein Method for producing dye-sensitized solar cells.

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