JP2013095938A - Film deposition apparatus and film deposition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the uniformity of the thickness of a film to be deposited on a substrate.SOLUTION: A film deposition apparatus includes a casing 150, a plurality of spraying mechanisms for spraying the microparticulated mist of a film deposition material 160 inside the casing 150, and a regulating means for making regulation so that the film deposition amount of the plurality of spraying mechanisms on a substrate 200 may be controlled to be within a prescribed range. The regulating means regulates the film deposition amount of each of the plurality of spraying mechanisms on the substrate 200, or regulates the film deposition amount on the substrate 200 for each spraying mechanism included in each of the plurality of groups in the plurality of spraying mechanisms divided into a plurality of groups in relation to the film deposition amount on the substrate 200.

Description

  The present invention relates to a film forming apparatus and a film forming method, and more particularly to a film forming apparatus and a film forming method for forming a film by depositing a fine film forming material.

  Transparent conductive films are widely used in fields such as semiconductors, displays, and solar cells. As the transparent conductive film, those made of metal oxides such as STO (strontium titanate) and ITO (Sn-doped indium oxide) are mainly used. The transparent conductive film is generally formed using a sputtering method, a vapor deposition method, a metal organic chemical vapor deposition method using an organic metal compound, or the like.

  In the sputtering method and the vapor deposition method, since a film is formed by a vacuum process, an equipment for forming and maintaining a vacuum atmosphere such as a vacuum vessel is required. In the organometallic chemical vapor deposition method, since the organometallic compound used as a raw material has explosiveness and toxicity, a highly confidential facility is required. For this reason, in order to perform the film forming method described above, an expensive film forming apparatus is required.

  Therefore, a mist method has been proposed as a film forming method different from the conventional one. The mist method is a method of forming a film by atomizing a solvent containing a raw material metal as a solute and spraying it on a substrate.

  In the mist method, a film can be formed at atmospheric pressure, so that no manufacturing equipment such as a vacuum vessel and pumps is required. In addition, since a dangerous substance such as an organometallic compound is not used in the mist method, an inexpensive film forming apparatus with a simple configuration can be used.

  Japanese Patent Application Laid-Open No. 2010-229460 (Patent Document 1) is a prior document that discloses a film forming method for switching the flow rate of a gas to be injected in order to form a film with a uniform film thickness. In the film forming method described in Patent Document 1, a gas containing powder is injected at a predetermined flow rate when a nozzle faces an effective area to be formed on a substrate surface, and an ineffective area other than the effective area The gas is injected at a flow rate larger than a predetermined flow rate when the nozzle faces the nozzle.

JP 2010-229460 A

  When a film is formed using a plurality of nozzles, the flow rate of mist sprayed from each nozzle varies. Further, the spraying flow rate of the nozzle changes with time. Therefore, it has been difficult to form a film with a uniform thickness on the substrate using a plurality of nozzles.

  The present invention has been made in view of the above problems, and an object thereof is to provide a film forming apparatus and a film forming method capable of improving the uniformity of the thickness of a film formed on a substrate. .

  A film forming apparatus according to the present invention is a film forming apparatus that deposits a fine film forming material on a substrate to form a film. The film forming apparatus includes a housing, a plurality of spray mechanisms for spraying mist obtained by atomizing a film forming material into the housing, and a film deposition amount on the substrate of the plurality of spray mechanisms within a predetermined range. And adjusting means for adjusting. The adjusting unit adjusts the film formation amount on each substrate of the plurality of spray mechanisms, or each of the plurality of groups in a plurality of spray mechanisms divided into a plurality of groups with respect to the film formation amount on the substrate. The amount of film formation on the substrate is adjusted for each spray mechanism included in.

  In one form of the present invention, each of the plurality of spray mechanisms comprises a spray nozzle. A spray nozzle sprays the mist which atomized the film-forming material with compressed air.

  In one embodiment of the present invention, the adjusting means adjusts the amount of film formation on the substrate by adjusting the flow rate of the compressed air.

  In one embodiment of the present invention, the adjusting means adjusts the amount of film formation on the substrate by adjusting the pressure of the film forming material solution.

  In one embodiment of the present invention, the film forming apparatus further includes a drive mechanism that operates the spray nozzle so as to approach or separate from the substrate. The adjusting means adjusts the amount of film formation on the substrate by adjusting the distance between the spray nozzle and the substrate by the driving mechanism.

  In one embodiment of the present invention, the film forming apparatus further includes a cooling unit that cools the spray nozzle.

  In one form of this invention, a cooling means approaches or leaves | separates with respect to a board | substrate in response to operation | movement of the spray nozzle by a drive mechanism.

  The film forming method according to the present invention includes an adjustment step of adjusting a film formation amount on a substrate of a plurality of spray mechanisms for spraying mist obtained by atomizing a film formation material into a predetermined range, and after the adjustment step, A spraying step of spraying mist that has been atomized by a plurality of spraying mechanisms. In the adjusting step, the amount of film formation on each substrate of the plurality of spray mechanisms is adjusted, or each of the plurality of groups in a plurality of spray mechanisms divided into a plurality of groups with respect to the amount of film formation on the substrate The amount of film formation on the substrate is adjusted for each spray mechanism included in.

  According to the present invention, the uniformity of the thickness of the film formed on the substrate can be improved.

It is a side view which shows the structure of the film-forming apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows the structure of the film-forming chamber contained in the film-forming apparatus which concerns on the embodiment. It is the figure which looked at the film-forming chamber of FIG. 2 from the arrow III direction. It is a schematic diagram which shows the external shape of the spray area | region of the spray nozzle used for the film-forming apparatus which concerns on the embodiment. It is a graph which shows the relative spraying intensity in the longitudinal direction of the spray area | region of the spray nozzle which concerns on the embodiment. It is a graph which shows the relative spraying intensity in the transversal direction of the spray area | region of the spray nozzle which concerns on the embodiment. It is a graph which shows the comparative spraying intensity | strength in the longitudinal direction of the spray area | region at the time of arrange | positioning 11 spray nozzles so that the longitudinal direction of each spray area | region may become a line as a 1st comparative example. It is a graph which shows the comparative spraying intensity | strength in the longitudinal direction of the spray area | region at the time of arrange | positioning nine spray nozzles so that the longitudinal direction of each spray area | region may become a line as a 2nd comparative example with a pitch of 120 mm. It is a graph which shows the comparative spraying intensity | strength in the longitudinal direction of a spray area | region at the time of arrange | positioning 8 spray nozzles so that the longitudinal direction of each spray area | region may become 1 row as a 3rd comparative example. It is a figure which shows the result of having investigated the spraying quantity (L / hr) of the spray nozzle 130 immediately after the start of 20 spraying, and compressed air consumption (L / min). It is a figure which shows the time-dependent change of the spray amount at the time of spraying mist in the spray nozzle which consists of Hastelloy (trademark), and the spray nozzle which consists of Hastelloy (trademark) and an alumina. It is a figure which shows the relationship between the spraying quantity of a spray nozzle, the mist diameter, and the pressure of compressed air. It is a figure which shows the relationship between the spraying quantity and mist diameter of a spray nozzle, and the pressure of the solution of the film-forming material. It is a figure which shows the relationship between the spraying quantity and mist diameter of a spray nozzle, and the nozzle diameter of a spray nozzle. It is a top view which shows the state in which the tank provided with the adjustment means for every spray nozzle contained in each group is connected. It is sectional drawing which shows the structure of the tank which concerns on the same embodiment.

  Hereinafter, a film forming apparatus according to an embodiment of the present invention will be described. In the following description of the embodiments, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated. In the present embodiment, film formation of a transparent conductive film used for a thin film solar cell will be described as an example, but the present invention can be applied to film formation of various films.

  FIG. 1 is a side view showing a configuration of a film forming apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a configuration of a film forming chamber included in the film forming apparatus according to the present embodiment. FIG. 3 is a view of the film forming chamber of FIG. 2 as viewed from the direction of arrow III. In FIG. 3, the spray mechanism is illustrated in a simplified manner.

  As shown in FIG. 1, a film forming apparatus 10 according to Embodiment 1 of the present invention includes an input unit 11 into which a substrate 200 is input, a preheating unit 12 in which the substrate 200 is preheated, and a substrate 200 that is subjected to a film forming process. A film forming unit 13, a slow cooling unit 14 for cooling the substrate 200, and a take-out unit 15 for taking out the substrate 200.

  As shown in FIGS. 1 to 3, the film forming apparatus 10 includes a transfer conveyor 110 that is a transfer unit that transfers the substrate 200 along the transfer path. The conveyor 110 is provided across the input unit 11, the preheating unit 12, the film forming unit 13, the slow cooling unit 14, and the takeout unit 15.

  The conveyor 110 includes a conveyor belt 111 on which the substrate 200 is placed, a pulley 112 around which the conveyor belt 111 is wound, a drive shaft 113 that drives the pulley 112, and a motor (not shown) that applies power to the drive shaft 113. It consists of and. The conveyor belt 111 is made of heat-resistant metal or resin.

  The substrate 200 is transported in the direction indicated by the arrow 114 by the transport conveyor 110. That is, in the film forming apparatus 10 according to the present embodiment, the transport path of the substrate 200 is linear in plan view. However, the conveyance path is not limited to a straight line, and the conveyance path may be bent in a plan view or may be a curved line.

  The film forming apparatus 10 includes a plurality of film forming chambers 100 (100a, 100b, 100c, 100d) positioned so as to be aligned in the transfer path. Specifically, a film formation chamber 100a, a film formation chamber 100b, a film formation chamber 100c, and a film formation chamber 100d are provided in this order from the upstream side in the transport direction of the substrate 200. In the present embodiment, four film formation chambers 100 (100a, 100b, 100c, 100d) are provided, but it is sufficient that one or more film formation chambers 100 are provided.

  Further, the film formation apparatus 10 is positioned in a tunnel shape along the transfer path so as to connect adjacent film formation chambers among the plurality of film formation chambers 100, and the substrate 200 that sequentially passes through the plurality of film formation chambers 100. A heating furnace 120 is provided for surrounding and heating. As shown in FIG. 3, the lower portion of the housing 150 is covered with the heating furnace 120.

  An opening is provided in the upper part of the tunnel-shaped heating furnace 120, and a housing 150 is incorporated in the opening. The heating furnace 120 is provided over the four film formation chambers 100 (100a, 100b, 100c, 100d). The heating furnace 120 is provided from the upstream side of the film forming chamber 100 a located upstream in the transport direction of the substrate 200 in order to preheat the substrate 200. That is, the heating furnace 120 is provided across the preheating unit 12 and the film forming unit 13.

  The substrate 200 is heated while being transported through the heating furnace 120 by the transport conveyor 110. When the film is formed on the substrate 200, the inside of the heating furnace 120 is maintained at substantially the same temperature, for example, 550 ° C.

  In the film forming chamber 100 according to the present embodiment, the fine film forming material 160 is deposited on the substrate 200 to form a film. As shown in FIG. 2, the film forming chamber 100 is provided with a casing 150 and a spray mechanism that sprays mist obtained by forming the film forming material 160 into fine particles inside the casing 150.

  The casing 150 has an exhaust port 152 for exhausting mist on one of the side walls. As shown in FIG. 1, one end of a connection pipe 310 is connected to the exhaust port 152. The other end of the connection pipe 310 is connected to an abatement apparatus 300 that is a gas processing means for detoxifying the exhausted mist.

  As shown in FIG. 2, the housing 150 has an inlet 151 into which the carrier gas 170 is introduced. The housing 150 also has a partition wall 154 that divides the interior of the housing 150 into three spaces. The first space is a spray mechanism arrangement space 158 in which a part of the spray mechanism is arranged. The second space is a mist spray space 159 in which mist is sprayed from the spray mechanism. The third space is an exhaust space 153 connected to the exhaust port 152.

  The casing 150 has an open portion that faces the substrate 200 and allows the mist to flow from the mist spray space 159 onto the substrate 200. The opening part is formed in the lower part of the housing 150. As shown in FIGS. 1 and 3, the open portion is located in the heating furnace 120. A predetermined gap is provided between the substrate 200 being transported by the transport conveyor 110 and the open portion of the housing 150.

  The spray mechanism includes a spray nozzle 130 that atomizes the film-forming material 160 with compressed air. Each of the plurality of spray mechanisms has a spray port. Specifically, the solution of the film-forming material 160 stored in the tank 140 is pressurized by compressed air from a compressor (not shown) and passed through the passage 141, and atomized mist is sprayed from the spray port of the spray nozzle 130. To do. An opening 155 is formed in the housing 150 corresponding to the position of the spray nozzle 130.

  A cooling jacket 131 which is a cooling means for cooling the spray nozzle 130 is attached to the end of the spray nozzle 130. The cooling jacket 131 is connected to a cooling water supply pipe (not shown), and the cooling water circulates inside the cooling jacket 131.

  Further, the film forming chamber 100 is provided with a cylindrical rectifying member 132 attached to the tip of the spray nozzle 130. In the present embodiment, the rectifying member 132 has a tapered rectifying part 134 that is located on the inner surface and rectifies the mist. However, the shape of the rectifying unit 134 is not limited to this, and may have a trumpet shape, for example.

  The rectifying member 132 is attached to the cooling jacket 131 by connecting a connecting member (not shown) connected to a part of the outer surface of the rectifying member 132 to a part of the outer surface of the cooling jacket 131.

  The spray nozzle 130 is a two-fluid spray nozzle that mixes two fluids of a film forming material 160 and compressed air to spray mist. Here, the mist means a state in which droplets having an average particle size of 0.1 μm or more and 100 μm or less are dispersed in a gas. The average particle diameter of the mist is a value calculated by the immersion method.

  However, the spray mechanism is not limited to the spray nozzle 130, and may be one that generates mist using ultrasonic waves. When the mist is generated by the ultrasonic vibrator, the average particle diameter of the mist can be made uniform as compared with the case where the mist is generated by the spray nozzle 130. Therefore, the generated mists aggregate before reaching the substrate 200. This can be suppressed.

As shown in FIG. 3, the plurality of spray nozzles 130 face the substrate 200 in the housing 150 and are arranged in a direction orthogonal to the transport direction of the substrate 200 at intervals. In FIG. 3, three spray nozzles 130 are arranged at the pitch L _p , but the number of spray nozzles 130 is not limited to three and may be plural.

  The number of spray nozzles 130 provided is the amount of mist sprayed per unit time necessary to satisfy the desired tact time of the film forming process of the substrate 200 or the film forming speed necessary for performing the film forming process. It will be changed accordingly.

The distance between the upper end of the heating furnace 120 and the substrate 200 is set to L _h / 4 with respect to the distance L _h between the spray port of the spray nozzle 130 and the upper surface of the substrate 200.

  A part of the carrier gas 170 introduced from the inlet 151 described later is sent to the spray nozzle 130 in order to cool the spray nozzle 130. In order to send the carrier gas 170 to the spray nozzle 130, a cooling fan (not shown) is disposed in the vicinity of the spray nozzle 130. The spray nozzle 130 is air-cooled by a cooling fan. Further, the spray nozzle 130 is water cooled by the cooling jacket 131 described above.

  In this way, by cooling the vicinity of the spray nozzle 130, the solution of the film forming material 160 before being sprayed from the spray nozzle 130 is cooled to a temperature equal to or lower than the boiling point. More preferably, the solution of the film forming material 160 is cooled to about room temperature.

  By this cooling, since the solvent in the solution of the film forming material 160 can be prevented from volatilizing in the spray nozzle 130, the concentration of the solution of the film forming material 160 to be sprayed can be kept constant. Further, solidification of the film forming material 160 due to volatilization of the solvent in the solution of the film forming material 160 in the spray nozzle 130 can be suppressed.

  As a result, since the film can be formed using the film forming material 160 having a constant concentration, the quality of the film formed on the substrate 200 can be stabilized. Further, the clogging of the spray nozzle 130 due to the solidified film forming material 160 can be suppressed.

  As a solution of the film forming material 160, a solution in which a chloride of an inorganic material selected from the group consisting of zinc, tin, indium, cadmium, and strontium is dissolved in a solvent can be used. As the solvent, water, methanol, ethanol, butanol and the like can be used. As the solution of the film forming material 160, for example, an aqueous solution containing zinc acetate, an aqueous solution containing indium tin oxide, an aqueous solution containing tin oxide, or the like can be used.

  However, the solution of the film forming material 160 is not limited to this, and various solutions can be used. The concentration of the film forming material 160 solution is not particularly limited, and is, for example, a concentration of 0.1 mol / L or more and 3 mol / L or less.

  Here, the flow path of the gas in the housing 150 will be described. First, a carrier gas 170 made of compressed air, for example, is introduced into the mist spray space 159 of the housing 150 from the introduction port 151. The carrier gas 170 introduced into the mist spray space 159 flows in the direction indicated by the arrow 171. As the carrier gas 170, for example, nitrogen, oxygen, hydrogen, and a mixed gas thereof can be used.

  Mist is sprayed from the spray nozzle 130 into the spray region 162 in the direction indicated by the arrow 161. The mist and the carrier gas 170 are mixed with each other in the mixing region 181 to become a mixed mist. The mixed mist flows in the direction indicated by the arrow 182 and reaches the open portion. The mixed mist is sprayed onto the main surface of the substrate 200 from the open portion. A region where the mixed mist containing mist is sprayed onto the substrate 200 is referred to as a spray region X.

  The mixed mist that has reached the spray region X flows along the main surface of the substrate 200. Specifically, the mixed mist flows in a direction indicated by an arrow 183 between a facing surface that is a part of the partition wall 154 and that faces the main surface of the substrate 200, and the main surface of the substrate 200. A region where the mixed mist flows in the direction indicated by the arrow 183 is referred to as a flow channel region Y.

  The mixed mist that has passed through the flow path region Y flows in the direction indicated by the arrow 184 in the exhaust space 153. A region where the mixed mist is directed from the main surface of the substrate to the exhaust port 152 is referred to as an exhaust region Z. The mixed mist that has passed through the exhaust space 153 and has reached the exhaust port 152 is rendered harmless by the detoxifying device 300 and discharged to the outside as the exhaust gas 180. In addition, in FIG. 2, the abatement apparatus 300 is not illustrated.

  The spray area X, the flow path area Y, and the exhaust area Z constitute an open portion. In each of the plurality of film forming chambers 100 (100a, 100b, 100c, 100d), the mist flows from the spray mechanism through the opening portion toward the exhaust port 152.

  In the exhaust port 152, the mixed mist is exhausted at a flow rate that is about 3 to 10 times larger than the carrier gas 170 introduced from the introduction port 151. However, the flow rate of the introduced carrier gas 170 and the exhaust flow rate of the mixed mist are appropriately set.

  As shown in FIG. 1, mist flows in the film forming chamber 100a as indicated by an arrow 400. In the film forming chamber 100b, mist flows as indicated by an arrow 410. In the film forming chamber 100c, mist flows as indicated by an arrow 420. In the film forming chamber 100d, mist flows as indicated by an arrow 430.

  As described above, the substrate 200 passes through the vicinity of the open portion while the mist is flowing, so that the substrate 200 is formed. In the film forming apparatus 10 of the present embodiment, the transfer conveyor 110 is provided so that the substrate 200 passes through the vicinity of the open part.

  The substrate 200 is transferred by the transfer conveyor 110 so as to sequentially pass through the spray region X, the flow channel region Y, and the exhaust region Z in each of the plurality of film forming chambers 100 (100a, 100b, 100c, 100d). . The substrate 200 is formed by depositing fine particles of the film forming material 160 on the main surface while passing through the spray region X, the flow channel region Y, and the exhaust region Z.

For example, the substrate 200 is formed with a plurality of films such as a SiO ₂ film as an alkali barrier layer and a transparent conductive oxide (TCO) as a transparent conductive film. Note that the alkali barrier layer is for preventing performance degradation of the solar cell due to alkali contained in the substrate 200. Therefore, when the substrate 200 is made of a material that does not contain much alkali, the alkali barrier layer need not be formed.

When different types of films are formed on the substrate 200 as described above, various mists are used in the plurality of film forming chambers 100 (100a, 100b, 100c, 100d). For example, a mist using SiO ₂ as the film forming material 160 is used in the film forming chamber 100a, and a mist using SnO ₂ as the film forming material 160 is used in the film forming chamber 100b.

When forming a transparent conductive film made of SnO ₂ , the temperature in the heating furnace 120 is preferably 450 ° C. or higher and 600 ° C. or lower, and more preferably 520 ° C. or higher and 580 ° C. or lower.

  When the temperature in the heating furnace 120 is lower than 450 ° C., the film formation rate is remarkably lowered by increasing the drying time of the mixed mist adhering to the substrate 200. On the other hand, when the temperature in the heating furnace 120 is higher than 600 ° C., the solvent contained in the mixed mist volatilizes before reaching the substrate 200 in a part of the mixed mist and loses the film forming performance. The amount of the mixed mist that reaches the temperature decreases, and the film formation rate significantly decreases.

  Further, by appropriately setting the spray pressure of the spray nozzle 130, the flow rate of the carrier gas 170, and the exhaust flow rate, the mixed mist can stably reach the upper surface of the substrate 200.

  In order to form a uniform film on the substrate 200 by the mixed mist generated by the above configuration, the mixed mist needs to reach the entire surface of the substrate 200. Here, the spray region of the spray nozzle 130 will be described.

FIG. 4 is a schematic diagram showing the outer shape of the spray region of the spray nozzle used in the film forming apparatus according to the present embodiment. As a solution of the film forming material 160, 0.9 mol / L SnCl ₄ .5H ₂ O, 0.3 mol / L NH ₄ F, 30% by volume HCl, and 2.5% by volume methanol are included. An aqueous solution was used. The boiling point of this aqueous solution was about 70 ° C.

As shown in FIG. 4, the spray area 162 of the spray nozzle 130, in a point distant distance L _h from the spray port of the spray nozzle 130, and has an outer elliptical.

Specifically, the length of the major axis has a L _W, elliptical length of the minor axis is L _T. That is, the spray region 162 has a longitudinal direction parallel to the major axis and a lateral direction parallel to the minor axis. The zero point in FIG. 4 is an intersection of the major axis and the minor axis, and is a position immediately below the center of the spray nozzle 130 in the vertical direction.

  FIG. 5 is a graph showing the relative spray strength in the longitudinal direction of the spray region of the spray nozzle according to the present embodiment. FIG. 6 is a graph showing the relative spray strength in the short direction of the spray region of the spray nozzle according to the present embodiment.

  In FIG. 5, the vertical axis represents the relative spray strength (%), and the horizontal axis represents the position (mm) from the zero point in the longitudinal direction of the spray region. In FIG. 6, the vertical axis represents the relative spray strength (%), and the horizontal axis represents the position (mm) from the zero point in the short direction of the spray region.

As shown in FIG. 5, at the point where L _h = 300 mm, the relative spray strength in the longitudinal direction of the spray region 162 of the spray nozzle 130 increases as the distance from the zero point increases to 100%, and then reaches 0%. As it goes away from the point, it descends to 0%.

As shown in FIG. 6, at the point where L _h = 300 mm, the relative spray strength in the short direction of the spray region 162 of the spray nozzle 130 is 100% at the zero point, and decreases as the distance from the zero point increases. It is 0%.

  Thus, in the spray region 162, the mist spraying strength is weaker at the end portion than just below the center of the spray nozzle 130. This tendency is the same when a plurality of spray nozzles 130 are provided.

  FIG. 7 is a graph showing, as a first comparative example, comparative spraying strength in the longitudinal direction of the spray area when 11 spray nozzles are arranged with a pitch of 100 mm so that the longitudinal direction of each spray area is in a line. It is. FIG. 8 is a graph showing the comparative spraying intensity in the longitudinal direction of the spray area when nine spray nozzles are arranged so that the longitudinal direction of each spray area is in a line as a second comparative example with a pitch of 120 mm. It is. FIG. 9 is a graph showing the comparative spraying intensity in the longitudinal direction of the spray area when the spray nozzle is arranged so that the longitudinal direction of each spray area is in a line with a pitch of 150 mm as a third comparative example. It is.

  7 to 9, the vertical axis represents the comparative spraying intensity (%), and the horizontal axis represents the position (mm) from the zero point in the longitudinal direction of the spray region arranged in a line. The comparative spray strength (%) indicates the spray strength when a plurality of spray nozzles are arranged at each pitch, with the maximum value of the relative spray strength of one spray nozzle as 100%. .

As shown in FIGS. 7 to 9, at the point where L _h = 300 mm, when the spray nozzle was arranged with a pitch of 120 mm, the comparative spraying strength in the longitudinal direction of the spray region was relatively uniform.

  When forming a film by arranging a plurality of spray nozzles 130 as in the film forming apparatuses of the first to third comparative examples, the spray amount of each spray nozzle 130 varies. Moreover, the spray amount of the spray nozzle 130 changes with time.

  FIG. 10 is a diagram showing the results of examining the spray amount (L / hr) of the spray nozzle 130 immediately after the start of 20 sprays and the compressed air consumption (L / min). As shown in FIG. 10, the spray amount of the spray nozzle 130 immediately after the start of spraying has a variation of about ± 10%.

  The change over time in the spray amount of the spray nozzle 130 varies depending on the material constituting the spray nozzle 130. For example, the time-dependent change of the spray amount when the solution of the film forming material 160 is sprayed differs between a spray nozzle made of Hastelloy (registered trademark) and a spray nozzle made of Hastelloy (registered trademark) and alumina.

  FIG. 11 is a diagram showing the change over time in the spray amount when mist is sprayed in a spray nozzle made of Hastelloy (registered trademark) and a spray nozzle made of Hastelloy (registered trademark) and alumina.

  As shown in FIG. 11, in the spray nozzle made of Hastelloy (registered trademark), the spray amount after 40 hours from the start of spraying increased by about 25% compared to the spray amount at the start of spraying. On the other hand, in the spray nozzle made of Hastelloy (registered trademark) and alumina, the spray amount was substantially constant. This is because in the spray nozzle made of Hastelloy (registered trademark), the inside of the nozzle is corroded by mist and the nozzle diameter is increased. Thus, the amount of change with time of the spray amount of the spray nozzle differs depending on the constituent material of the spray nozzle.

  The spray amount of the spray nozzle varies depending on other factors. FIG. 12 is a diagram illustrating the relationship between the spray amount of the spray nozzle, the mist diameter, and the pressure of the compressed air. FIG. 13 is a diagram showing the relationship between the spray amount and mist diameter of the spray nozzle and the pressure of the film forming material solution. FIG. 14 is a diagram illustrating the relationship between the spray amount and mist diameter of the spray nozzle and the nozzle diameter of the spray nozzle.

  In FIG. 12, the vertical axis represents the spray amount and the mist diameter, and the horizontal axis represents the pressure of the compressed air. In FIG. 13, the vertical axis represents the spray amount and the mist diameter, and the horizontal axis represents the pressure of the film forming material solution. In FIG. 14, the vertical axis represents the spray amount and the mist diameter, and the horizontal axis represents the nozzle diameter of the spray nozzle. 12 to 14, the spray amount is indicated by a dotted line, and the mist diameter is indicated by a solid line.

  As shown in FIG. 12, as the pressure of the compressed air mixed with the solution of the film forming material 160 increases, the diameter of the sprayed mist decreases. Further, as the pressure of the compressed air increases, the spray amount of the spray nozzle increases to some extent and then decreases.

  As shown in FIG. 13, as the pressure of the solution of the film forming material 160 increases, the diameter of the sprayed mist increases and the spray amount of the spray nozzle increases. As shown in FIG. 14, as the nozzle diameter of the spray nozzle increases, the diameter of the sprayed mist increases and the spray amount of the spray nozzle slightly increases.

  As described above, factors having a correlation with the spray amount of the spray nozzle include the pressure of the compressed air and the pressure of the solution of the film forming material. By controlling these factors, the mist can be sprayed at a desired spray amount from the spray nozzle. The amount of film formation on the substrate 200 can be adjusted by spraying the mist at a desired spray amount on the plurality of spray nozzles 130.

  Therefore, the film forming apparatus 10 according to the present embodiment includes an adjusting unit that adjusts the film forming amounts of the plurality of spray mechanisms on the substrate 200 so as to fall within a predetermined range. The adjusting unit adjusts the film formation amount on the substrate for each spray mechanism included in each of the plurality of groups in the plurality of spray mechanisms divided into the plurality of groups with respect to the film formation amount on the substrate 200. .

  For example, in the case where a film is formed on the substrate 200 using the 20 spray nozzles 130 shown in FIG. 10, the 20 spray nozzles 130 are divided into four groups according to the spray amount. Nozzle No. The spray nozzles 5, 8, 18, and 20 are group A. No. 1, 2, 12, and 17 spray nozzles are group B. The spray nozzles 3, 10, and 15 are group C, and the nozzle No. The spray nozzles 4, 9, and 19 are defined as a D group.

  FIG. 15 is a plan view showing a state in which a tank provided with adjusting means is connected to each spray nozzle included in each group. As shown in FIG. 15, the spray nozzles 130 are arranged in two rows in the transport direction of the substrate 200. The spray nozzles 130 may be arranged in a single row, but in the case where the spray nozzles 130 are arranged in two rows, it is possible to increase the conveyance speed of the substrate 200 and perform the film formation process, so that the film formation time can be reduced. The spray nozzles 130 arranged in two rows are arranged in a staggered manner. By arranging in this way, a uniform film can be formed on the substrate 200.

  Each of the spray nozzles 130 included in the group A is connected to the tank 140a via the passage 141. Each of the spray nozzles 130 included in the group B is connected to the tank 140b via the passage 141. Each of the spray nozzles 130 included in the group C is connected to the tank 140 c via a passage 141. Each of the spray nozzles 130 included in the group D is connected to the tank 140d via a passage 141.

  FIG. 16 is a cross-sectional view showing the configuration of the tank according to the present embodiment. Although the tank 140 is illustrated in a simplified manner in FIG. 2, the tank 140 has a double structure as shown in FIG. Specifically, the tank 140 includes an outer container 142 and an inner container 143 located in the outer container 142. The solution of the film forming material 160 is stored in the inner container 143.

  The outer container 142 is connected to a pressure adjusting unit 500 serving as an adjusting unit via a pipe 510. The inner container 143 has an opening 145, and the space 146 in the inner container 143 and the space 144 of the outer container 142 communicate with each other through the opening 145. The passage 141 passes through the outer container 142 and the inner container 143, and the end of the passage 141 is located in the solution of the film forming material 160.

  When the inside of the space 144 of the outer container 142 is pulled to a negative pressure by the pressure adjusting unit 500, the inside of the space 146 in the inner container 143 is pulled to a negative pressure through the opening 145. As a result, the pressure of the solution of the film forming material 160 is decreased. On the contrary, when the inside of the space 144 of the outer container 142 is pressurized by the pressure adjusting unit 500, the inside of the space 146 in the inner container 143 is pressurized through the opening 145. As a result, the pressure of the solution of the film forming material 160 increases. As described above, the pressure of the solution of the film forming material 160 can be adjusted by the pressure adjusting unit 500.

  Since the tank 140 is connected to each group of the spray nozzles 130, the pressure of the solution of the film forming material 160 can be adjusted for each group. Therefore, the amount of film formation on the substrate can be adjusted by adjusting the spray amount of the spray nozzle 130 for each group.

  The adjusting means may adjust the driving of the compressor that supplies the compressed air. By adjusting the drive of the compressor, the pressure of the compressed air can be adjusted.

  Also in this case, since the tank 140 is connected to each group of the spray nozzles 130, the pressure of the compressed air can be adjusted for each group. Therefore, the amount of film formation on the substrate can be adjusted by adjusting the spray amount of the spray nozzle 130 for each group.

  As described above, the spray nozzles 130 having a similar spray amount immediately after the start of spraying are grouped together to adjust the spray amount so that the film formation amount of the many spray nozzles 130 can be adjusted with high accuracy and the apparatus. The configuration can be prevented from becoming complicated.

  However, the adjusting means may adjust the spray amount of each of the plurality of spray nozzles 130. The adjusting means adjusts the pressure of the compressed air or the pressure of the solution of the film forming material at each spray nozzle 130, so that the amount of film formation on the substrate 200 is set to the spray amount at each spray nozzle 130 as a desired spray amount. Can be adjusted.

  Furthermore, the film forming apparatus 10 may further include a drive mechanism (not shown) that operates the spray nozzle 130 so as to approach or separate from the substrate 200. In this case, the adjusting means can adjust the film formation amount by adjusting the distance between the spray nozzle 130 and the substrate 200 by this driving mechanism.

  Specifically, by increasing the distance between the spray nozzle 130 and the substrate 200, the amount of mist that reaches the substrate 200 is increased to increase the amount of film formation. Conversely, by separating the distance between the spray nozzle 130 and the substrate 200, the amount of mist that reaches the substrate 200 is reduced, thereby reducing the amount of film formation.

  The drive mechanism may move the spray nozzle 130 main body, or may extend and contract only the end of the spray nozzle 130.

  In this case, the cooling jacket 131 approaches or separates from the substrate 200 in conjunction with the operation of the spray nozzle 130 by the drive mechanism. By doing so, it is possible to spray mist from the spray nozzle 130 while cooling the spray nozzle 130.

  As a result, when the spray nozzle 130 approaches the substrate 200 and approaches the heating furnace 120, the spray nozzle 130 can be prevented from becoming clogged by suppressing the temperature of the spray nozzle 130 from becoming high.

  In the present embodiment, the cooling jacket 131 and the rectifying member 132 are provided, but the cooling jacket 131 and the rectifying member 132 are not necessarily provided.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 10 Film-forming apparatus, 11 Input part, 12 Preheating part, 13 Film-forming part, 14 Slow cooling part, 15 Taking-out part, 100, 100a, 100b, 100c, 100d Film-forming chamber, 110 Conveyor, 111 Conveyor belt, 112 Pulley , 113 drive shaft, 120 heating furnace, 130 spray nozzle, 131 cooling jacket, 132 rectifying member, 134 rectifying unit, 140, 140a, 140b, 140c, 140d tank, 141 passage, 142 outer container, 143 inner container, 145 opening 144, 146 space, 150 housing, 151 inlet, 152 exhaust port, 153 exhaust space, 154 partition wall, 155 opening, 158 spray mechanism arrangement space, 159 mist spray space, 160 film forming material, 162 spray region, 170 carrier gas, 180 exhaust gas, 181 Mixing area, 200 substrate, 300 abatement device, 310 connecting pipe, 500 pressure adjusting part, 510 piping, X spraying area, Y flow area, Z exhaust area.

Claims (8)

A film forming apparatus for depositing a fine film forming material on a substrate to form a film,
A housing,
A plurality of spray mechanisms for spraying mist obtained by atomizing the film forming material into the housing;
Adjusting means for adjusting the film formation amount on the substrate of the plurality of spray mechanisms so as to fall within a predetermined range;
The adjusting means adjusts the film formation amount on each substrate of the plurality of spray mechanisms, or the plurality of spray mechanisms divided into a plurality of groups with respect to the film formation amount on the substrate. A film forming apparatus for adjusting a film forming amount on a substrate for each spray mechanism included in each group. Each of the plurality of spray mechanisms comprises a spray nozzle,
The film forming apparatus according to claim 1, wherein the spray nozzle sprays the mist obtained by atomizing the film forming material with compressed air.   The film forming apparatus according to claim 2, wherein the adjusting unit adjusts a film forming amount on the substrate by adjusting a flow rate of the compressed air.   The film forming apparatus according to claim 2, wherein the adjusting unit adjusts a film forming amount on the substrate by adjusting a pressure of the solution of the film forming material. A drive mechanism for operating the spray nozzle to approach or separate from the substrate;
5. The film forming apparatus according to claim 2, wherein the adjusting unit adjusts a film forming amount on the substrate by adjusting a distance between the spray nozzle and the substrate by the driving mechanism.   The film forming apparatus according to claim 5, further comprising a cooling unit that cools the spray nozzle.   The film forming apparatus according to claim 6, wherein the cooling unit approaches or separates from the substrate in conjunction with the operation of the spray nozzle by the driving mechanism. An adjustment step of adjusting the amount of film formation on the substrate of a plurality of spray mechanisms for spraying mist obtained by atomizing the film formation material into a predetermined range;
A spraying step of spraying the mist finely divided by the plurality of spraying mechanisms after the adjusting step;
In the adjusting step, the amount of film formation on each substrate of the plurality of spray mechanisms is adjusted, or the plurality of spray mechanisms divided into a plurality of groups with respect to the amount of film formation on the substrate. A film forming method for adjusting a film forming amount on a substrate for each spray mechanism included in each group.

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