JP2012196623A - Film-forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a high-quality film, while achieving the reduction of a film formation cost, by reducing the frequency of the maintenance of a film-forming device and also improving the utilization efficiency of a film formation material.SOLUTION: The film-forming device 100 forms a film by depositing the microparticulated film formation material 160 on a substrate 200. The film-forming device includes: a housing 150; an atomization mechanism that sprays a film formation gas, obtained by microparticulating the film formation material 160, in the housing 150; and an electric field formation mechanism that generates an electric field near a prescribed part so that the film formation material 160 does not adhere to the prescribed part of a wall surface of the housing 150.

Description

  The present invention relates to a film forming apparatus, and more particularly to a film forming apparatus that deposits a fine film forming material to form a film.

  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. The organometallic chemical vapor deposition method is difficult to handle because the organometallic compound used as a raw material is explosive and toxic, and it is necessary to provide an accompanying facility such as an exhaust gas treatment apparatus. 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 the mist method does not use a dangerous substance such as an organometallic compound, it is possible to use an inexpensive film forming apparatus with a simple configuration.

  There is Patent Document 1 as a prior document disclosing a film forming apparatus that performs a mist method. In the film forming apparatus described in Patent Document 1, a solution containing a ferroelectric material is made mist and the mist is charged. The mist is accelerated on the conductive electrode provided on the substrate by accelerating the mist with an electric field applied between the conductive electrode provided on the substrate and an electrode installed at a position away from the substrate. ing.

JP 2002-289803 A

  In a film forming apparatus using the mist method, fine particles of the film forming material adhere to the wall surface of the film forming apparatus other than the substrate that is the object of processing, and therefore maintenance is frequently required to remove the fine particles. In addition, the fine particles adhering to the wall surface of the flow path region of the mist located between the film formation region in the film formation apparatus and the exhaust region leading to the exhaust port are dropped from the wall surface onto the substrate to form a film. As a result, the quality of the film is reduced and the utilization efficiency of the film forming material is reduced.

  The present invention has been made in view of the above-described problems, and reduces the frequency of maintenance of the film forming apparatus and improves the use efficiency of the film forming material, while reducing the film forming cost. An object of the present invention is to provide a film forming apparatus capable of forming the above film.

  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 spray mechanism for spraying a film forming gas obtained by atomizing the film forming material into the housing, and the vicinity of the predetermined location so that the film forming material does not adhere to the predetermined location on the wall surface of the housing. And an electric field generating mechanism for generating an electric field.

  In one embodiment of the present invention, the housing has an exhaust port for exhausting the film forming gas. The film forming gas passes through a flow channel region in which the film forming gas flows along the substrate from the spraying area where the film forming gas is sprayed onto the substrate, and the film forming gas is discharged from the substrate to the exhaust port. Flows to the exhaust area toward The predetermined location is a wall surface of the housing located in the flow path region.

  Preferably, the film forming apparatus includes a transport mechanism that transports the substrate so as to sequentially pass through the spraying region, the flow channel region, and the exhaust region, and the main surface side opposite to the main surface on which the film forming material is deposited. And a heating mechanism for heating the.

  Preferably, the electric field generating mechanism includes a base made of an insulator and a thin wire electrode made of metal provided in the base. Preferably, the insulator is ceramic. Preferably, the metal is tungsten.

  Preferably, a plurality of fine wire electrodes are provided substantially in parallel. Preferably, a voltage of 5 kV to 10 kV is applied to the thin wire electrode.

  In one embodiment of the present invention, a plurality of thin wire electrode groups each composed of a plurality of thin wire electrodes are arranged substantially in parallel while being displaced in the thickness direction of the substrate. An AC voltage of 5 kV or more and 10 kV or less is applied to each of the plurality of thin wire electrode groups independently of each other.

  In one embodiment of the present invention, a plurality of thin wire electrode groups each composed of a plurality of thin wire electrodes are arranged substantially in parallel while being displaced in the thickness direction of the substrate. An AC pulse voltage of 5 kV or more and 10 kV or less is applied to each of the plurality of thin wire electrode groups independently of each other.

  According to the present invention, it is possible to form a high-quality film while reducing the deposition cost by reducing the frequency of maintenance of the deposition apparatus and improving the utilization efficiency of the deposition material.

It is sectional drawing which shows the structure of the film-forming apparatus which concerns on Embodiment 1 of this invention. It is a top view which shows the structure of the electric field curtain panel which concerns on the same embodiment. It is sectional drawing seen from the III-III line arrow direction of FIG. It is a circuit diagram which shows the structure of the voltage application apparatus which concerns on the same embodiment. It is a model figure explaining the principle of an electric field curtain. 6 is a graph showing experimental results of film formation processing in the film formation apparatus of Embodiment 1 and the film formation apparatus of a comparative example. It is a top view which shows the structure of the electric field curtain panel which concerns on Embodiment 2 of this invention. It is sectional drawing seen from the VIII-VIII line arrow direction of FIG. It is a circuit diagram which shows the structure of the voltage application apparatus which concerns on the same embodiment. 10 is a graph showing experimental results of film formation processing in the film formation apparatus of Embodiment 2.

  Hereinafter, the film forming apparatus according to Embodiment 1 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.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing a configuration of a film forming apparatus according to Embodiment 1 of the present invention. As shown in FIG. 1, a film forming apparatus 100 according to Embodiment 1 of the present invention is an apparatus that deposits a fine film forming material 160 on a substrate 200 to form a film.

  The film forming apparatus 100 includes a housing 150, a spray mechanism that sprays a film forming gas obtained by atomizing the film forming material 160 into the housing 150, and the film forming material 160 does not adhere to a predetermined location on the wall surface of the housing 150. Thus, an electric field generating mechanism for generating an electric field in the vicinity of the predetermined portion is provided.

  The casing 150 has an introduction port 151 into which a carrier gas 170 described later is introduced, and an exhaust port 152 for exhausting the film forming gas. 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 film forming gas spray space 159 in which the film forming gas is sprayed from the spray mechanism. The third space is an exhaust space 153 connected to the exhaust port 152.

  The housing 150 has an opening 157 that allows the deposition gas to flow from the deposition gas spray space 159 onto the substrate 200. By disposing the substrate 200 in the vicinity of the opening 157, the substrate 200 is subjected to film formation.

  In the film forming apparatus 100 of this embodiment, a transport mechanism 110 that can transport the substrate 200 so as to pass through the vicinity of the opening 157 is provided. The transport mechanism 110 includes a transport belt 111 on which the substrate 200 is placed, a pulley 112 around which the transport 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.

  Although the transport mechanism 110 is provided in this embodiment, the transport mechanism 110 is not necessarily provided, and a mounting table on which the substrate 200 is mounted may be provided in the vicinity of the opening 157.

  A heating mechanism 120 for heating the substrate 200 from the main surface side opposite to the main surface on which the film forming material 160 is deposited is provided below the conveyance belt 111 on which the substrate 200 is placed. In the present embodiment, the heating mechanism 120 is configured by a hot plate. However, the heating mechanism 120 may be anything that can heat the substrate 200, and may be an infrared heater, for example.

  In addition, the heating mechanism 120 is not necessarily provided. However, when the surface temperature of the substrate 200 is low, it is difficult to form a metal oxide thin film, and thus it is preferable to provide the heating mechanism 120.

  The spray mechanism includes a tank 140 that stores the film forming material 160, a compressor (not shown) that introduces compressed air into the tank 140, a passage 141 through which the film forming material 160 pressurized by the compressed air passes, and a film forming material. A spray nozzle 130 that atomizes 160 and sprays it as a film forming gas. An opening 155 is formed in the housing 150 corresponding to the position of the spray nozzle 130.

  The number of spray nozzles 130 provided is the amount of film forming gas sprayed per unit time necessary to satisfy the desired tact time of the film forming process of the substrate 200, or the film forming necessary for performing the film forming process. It is changed appropriately according to the speed.

  The film forming material 160 includes at least one of materials such as zinc, tin, indium, cadmium, and strontium as an inorganic material. When these inorganic materials are dissolved as a solute in a solvent made of an organic metal or a chloride metal at a concentration of 0.1 mol / L or more and 3 mol / L or less, a solution of the film forming material 160 is produced. However, the solution of the film forming material 160 is not limited to this, and various solutions can be used.

  Here, the flow path of the gas in the housing 150 will be described. First, a carrier gas 170 made of, for example, compressed air is introduced into the film forming gas spray space 159 of the housing 150 from the introduction port 151. The carrier gas 170 introduced into the film forming gas spray space 159 flows in the direction indicated by the arrow 171.

  A film forming gas is sprayed from the spray nozzle 130 in the direction indicated by the arrow 161. The film forming gas and the carrier gas 170 are mixed with each other in the mixing region 181 to become mixed mist. The mixed mist flows in the direction indicated by the arrow 182 and reaches the opening 157.

  The mixed mist is sprayed onto the main surface of the substrate 200 from the opening 157. A region where the mixed mist containing the deposition gas 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 156 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 an abatement apparatus (not shown) and discharged to the outside as an exhaust gas 180.

  The substrate 200 is transported in the direction indicated by the arrow 114 by the transport mechanism 110. That is, the substrate 200 is transported so as to pass through the spray region X, the flow channel region Y, and the exhaust region Z in order. 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.

  However, the fine particles of the film forming material 160 also adhere to the wall surface of the housing 150 with which the film forming gas is in contact. In particular, the fine particles of the film forming material 160 are likely to adhere to the facing surface 156 of the partition wall 154 located in the flow path region Y due to the rising airflow generated when the substrate 200 is heated by the heating mechanism 120.

  When fine particles of the film forming material 160 adhere to the facing surface 156 of the partition wall 154 located in the flow channel region Y, the attached film forming material 160 drops off on the main surface of the substrate 200, and the film formed This causes a reduction in quality and a reduction in utilization efficiency of the film forming material 160. Therefore, in the conventional film forming apparatus, in order to maintain the quality of the film formed on the substrate 200, maintenance for removing the fine particles attached to the facing surface 156 of the partition wall 154 is frequently required.

  Therefore, in the film forming apparatus 100 of this embodiment, an electric field curtain panel 190 that is an electric field generation mechanism that generates an electric field is provided in the vicinity of the facing surface 156 of the partition wall 154 located in the flow path region Y. A voltage applying device 400 is connected to the electric field curtain panel 190.

  FIG. 2 is a plan view showing the configuration of the electric field curtain panel according to the present embodiment. 3 is a cross-sectional view seen from the direction of arrows III-III in FIG. In FIG. 3, the extraction electrode 195 is also shown for simplicity.

  As shown in FIGS. 2 and 3, the electric field curtain panel 190 according to the present embodiment includes a base 192 made of an insulator and thin wire electrodes 193 and 194 made of metal provided in the base 192.

  In the present embodiment, the base 192 is configured using ceramics as an insulator. Further, the thin wire electrodes 193 and 194 were formed using tungsten plated with platinum. However, the material of the base 192 and the thin wire electrodes 193 and 194 is not limited to these, and any material that functions as an electric field curtain panel may be used.

  A plurality of thin wire electrodes 193 are provided substantially parallel to each other at a predetermined interval to constitute a first thin wire electrode group. Similarly, a plurality of thin wire electrodes 194 are provided substantially parallel to each other at a predetermined interval to constitute a second thin wire electrode group. In a plan view, the fine wire electrodes 193 and the fine wire electrodes 194 are alternately arranged. The first thin wire electrode group and the second thin wire electrode group are arranged substantially in parallel while being displaced in the thickness direction of the base 192. In the present embodiment, the fine wire electrodes 193 and the fine wire electrodes 194 are provided on a 100 mm square base 192 at a pitch of 5 mm.

  Each thin wire electrode 193 of the first thin wire electrode group is connected to a lead electrode 195 drawn from the surface of the base 192. A part of the extraction electrode 195 extends in the base 192 in a direction substantially orthogonal to the direction in which the thin wire electrodes 193 are arranged, and is connected to each thin wire electrode 193 of the first thin wire electrode group. Further, the remaining portion of the extraction electrode 195 extends in the thickness direction of the base 192 from a contact point with any of the thin wire electrodes 193 and protrudes from the surface of the base 192. The extraction electrode 195 is made of the same material as the thin wire electrode 193.

  Each thin wire electrode 194 of the second thin wire electrode group is connected to a lead electrode 196 drawn from the surface of the base 192. A part of the extraction electrode 196 extends in the base 192 in a direction substantially orthogonal to the direction in which the thin wire electrodes 194 are arranged, and is connected to each thin wire electrode 194 of the second thin wire electrode group. The remaining portion of the extraction electrode 196 extends from the contact point with any one of the thin wire electrodes 194 in the thickness direction of the base 192 and protrudes from the surface of the base 192. The extraction electrode 196 is made of the same material as the thin wire electrode 194. The extraction electrodes 195 and 196 are connected to the voltage application device 400.

  FIG. 4 is a circuit diagram showing a configuration of the voltage application device according to the present embodiment. As shown in FIG. 4, the voltage application device 400 according to the present embodiment includes an electric field control unit 410, an AC signal generation device 420, a phase inversion device 430, a first amplifier 450 and a second amplifier 440.

  A function generator was used as the AC signal generator 420. The AC signal generator 420 connected to the electric field control unit 410 is connected to the first amplifier 450 via the contact 460. The AC signal generator 420 is connected to the phase inverter 430 and the second amplifier 440 via the contact 460.

  The first amplifier 450 is connected to the extraction electrode 195 of the electric field curtain panel 190. The second amplifier 440 is connected to the extraction electrode 196 of the electric field curtain panel 190.

  An AC voltage is applied from the voltage application device 400 to each thin wire electrode 193 of the first thin wire electrode group via the extraction electrode 195 and to each thin wire electrode 194 of the second thin wire electrode group via the extraction electrode 196. Thus, a so-called electric field curtain is formed.

  A standing wave electric field curtain is formed by applying AC voltages that are 180 ° out of phase to each of the thin wire electrodes 193 of the first thin wire electrode group and each of the thin wire electrodes 194 of the second thin wire electrode group. The

  In this embodiment, the electric field curtain panel 190 including two sets of fine wire electrodes is used. However, for example, when three sets of fine wire electrodes are used, a voltage whose phase is shifted by 120 degrees between two adjacent thin wire electrodes. Is applied to form a traveling wave electric field curtain. When four groups of thin wire electrodes are used, a traveling wave electric field curtain is formed by applying a voltage whose phase is shifted by 90 degrees to two adjacent thin wire electrodes.

  FIG. 5 is a model diagram illustrating the principle of the electric field curtain. As shown in FIG. 5, when the voltage applied to each of the adjacent thin wire electrode 193 and the thin wire electrode 194 is reversed, the electric lines of force 310 formed between the thin wire electrode 193 and the thin wire electrode 194 are substantially arc-shaped. It becomes.

  By applying an alternating voltage to each of the fine wire electrode 193 and the fine wire electrode 194, the direction of the electric field vector of the electric lines of force 310 is inverted at a constant period. When the fine particles 300 of the film forming material 160 approach the vicinity of the electric force lines 310, the fine particles 300 receive the electrostatic force 320 in the tangential direction of the electric force lines 310 and move along the electric force lines 310. Since the electric force lines 310 are substantially arc-shaped, a centrifugal force 330 acting outward in the radial direction of the electric force lines 310 acts on the fine particles 300. As a result, the fine particles 300 move in a direction away from between the fine wire electrode 193 and the fine wire electrode 194.

  If the frequency of the alternating voltage applied from the voltage application device 400 is set sufficiently high, the fine particles 300 can be moved in the opposite direction to the fine wire electrodes 193 and the fine particles 300 directed to the fine wire electrodes 194. Adhesion to the base 192 can be prevented.

  The frequency of the AC voltage is preferably 1 kHz or more and 5 kHz or less when the ambient temperature of the electric field curtain panel 190 is room temperature, and 30 Hz or more and 100 Hz or less when the ambient temperature of the electric field curtain panel 190 is about 500 ° C. Is preferred.

  The magnitude of the AC voltage is preferably 5 kV or more and 10 kV or less. In the present embodiment, the voltage application device 400 applies AC voltages of 5 kV or more and 10 kV or less independently to each of the first thin wire electrode group and the second thin wire electrode group.

  As shown in FIG. 1, in the film forming apparatus 100, the electric field curtain panel 190 is fixed by a mounting member 191 along the facing surface 156 of the partition wall 154. Therefore, when an AC voltage is applied by the voltage application device 400, the fine particles 300 of the film forming material 160 included in the mixed mist flowing in the flow path region Y move toward the main surface side of the substrate 200.

  As a result, adhesion of the fine particles 300 of the film forming material 160 to the facing surface 156 can be suppressed. Further, the fine particles 300 of the film forming material 160 can be deposited on the main surface of the substrate 200. Therefore, it is possible to form a high-quality film while reducing the film formation cost by reducing the frequency of maintenance of the film formation apparatus 100 and improving the utilization efficiency of the film formation material 160.

  In the present embodiment, the electric field curtain panel 190 is provided on the facing surface 156. However, the position where the electric field curtain panel 190 is provided is not limited to this, and may be provided at a position where the deposition of the film forming material 160 is desired to be suppressed.

  For details of the electric field curtain, see Yuki Takahata and one other, “Analysis of the Movement of Charged Particles on the Electric Field Curtain”, Journal of the Electrostatic Society, May 2009, Vol. 33, No. 3, p. See 121-127.

  Hereinafter, an experimental example in which the substrate 200 is subjected to the film formation process in the film formation apparatus of the comparative example that does not have the electric field curtain panel 190 and the film formation apparatus 100 according to the first embodiment will be described.

(Experiment 1)
As shown in FIG. 1, the substrate 200 is arranged so as to extend over the spray region X, the flow channel region Y, and the exhaust region Z. In this experiment, the substrate 200 was placed at a fixed position without carrying the substrate 200 by the carrying mechanism 110. The size of the substrate 200 is 100 mm square, and the size of the spray region X is 80 mm square.

  Three spray nozzles 130 were provided in each film forming apparatus, and the water head difference between the spray port of each spray nozzle 130 and the main surface of the substrate 200 was set to −150 mm.

  In the film forming apparatus 100, a voltage application apparatus 400 applied a voltage having a frequency of 20 kHz and an output voltage of ± 8 kV to the thin wire electrodes 193 and 194 to flow an output current of 50 mA.

  The film was formed for 60 seconds at a set temperature of 590 ° C. of the hot plate serving as the heating mechanism 120. The temperature of the portion of the substrate 200 located in the spray region X decreased from about 590 ° C. immediately after the start of the film forming process to about 500 ° C. This is because when the mixed mist adheres to the main surface of the substrate 200 and vaporizes, the heat of vaporization is taken from the substrate 200.

  The temperature of the substrate 200 in the portion located in the flow path region Y was higher than the temperature of the substrate 200 in the portion located in the spray region X. This is because the amount of mixed mist that comes into contact with the substrate 200 in the flow path region Y is small, and a part of the high-temperature gas vaporized in the spray region X flows into the flow path region Y. Therefore, in the flow channel region Y, the deposition efficiency of the film forming material 160 is high.

  FIG. 6 is a graph showing experimental results of film formation processing in the film formation apparatus of Embodiment 1 and the film formation apparatus of the comparative example. In FIG. 6, the vertical axis represents the film thickness (nm) of the deposited film, and the horizontal axis represents the distance (mm) from the substrate end on the exhaust region side.

  As shown in FIG. 6, in both the film forming apparatus 100 of the first embodiment and the film forming apparatus of the comparative example, the film thickness of the film forming material 160 formed on the main surface of the substrate 200 is the spray region X. The channel region Y and the exhaust region Z become thinner in this order.

  The film thickness of the film forming material 160 formed on the main surface of the substrate 200 was almost the same in the spray region X between the film forming apparatus of the comparative example and the film forming apparatus 100 according to the first embodiment. . In the flow path region Y and the exhaust region Z, the film thickness of the deposited film was larger in the film deposition apparatus 100 according to the first embodiment than in the film deposition apparatus of the comparative example.

  This is because fine particles of the film forming material 160 are moved toward the substrate 200 in the flow path region Y and the exhaust region Z by the electric field curtain panel 190 in the film forming apparatus 100 of the first embodiment, and are on the main surface of the substrate 200. It is because it was deposited.

  As a result, in the utilization efficiency of the film forming material 160, the film forming apparatus 100 according to the first embodiment was improved to 12.5% while the film forming apparatus of the comparative example was 10.2%. The measured value of the sheet resistance of the transparent conductive film having a thickness of 800 nm or more formed by the film forming apparatus 100 is about 50Ω / □ on average, the average haze ratio is 10%, and a high quality film is formed. It was.

  On the other hand, in the film forming apparatus 100, the film forming material 160 hardly adhered to the facing surface 156 of the partition wall 154. Therefore, the number of maintenance operations can be reduced in the film formation apparatus 100.

  It has been confirmed that the same effect can be obtained in both cases of the pulsed uneven waveform and the sine waveform as the output waveform of the voltage applied by the voltage application device 400. Since the effect of the electric field curtain panel 190 is not significantly affected by the output waveform of the applied voltage, for example, it is considered that a voltage having an output waveform such as a triangular waveform may be applied.

  Furthermore, the voltages applied to the fine wire electrode 193 and the fine wire electrode 194 do not have to be in opposite phases, and various electric fields can be applied between the fine wire electrode 193 and the fine wire electrode 194. Therefore, AC pulse voltages of 5 kV or more and 10 kV or less may be applied to each of the plurality of thin wire electrode groups independently of each other.

  Hereinafter, a film forming apparatus according to Embodiment 2 of the present invention will be described. The film forming apparatus according to the second embodiment is different from the film forming apparatus 100 according to the first embodiment only in the configuration of the electric field curtain panel 500 and the voltage applying device 600, and therefore, the description of the other configurations will not be repeated.

(Embodiment 2)
FIG. 7 is a plan view showing the configuration of the electric field curtain panel according to Embodiment 2 of the present invention. FIG. 8 is a cross-sectional view seen from the direction of arrows VIII-VIII in FIG. In FIG. 8, extraction electrodes 506, 507, and 508 are also shown for simplicity.

  As shown in FIGS. 7 and 8, the electric field curtain panel 500 according to the present embodiment includes a base body 501 made of an insulator and fine wire electrodes 502, 503, 504, and 505 made of metal provided in the base body 501.

  A plurality of thin wire electrodes 502 are provided substantially parallel to each other at a predetermined interval to constitute a first thin wire electrode group. A plurality of thin wire electrodes 503 are provided substantially parallel to each other at a predetermined interval to constitute a second thin wire electrode group. A plurality of thin wire electrodes 504 are provided substantially parallel to each other at a predetermined interval to constitute a third thin wire electrode group. A plurality of thin wire electrodes 505 are provided substantially parallel to each other at a predetermined interval to constitute a fourth thin wire electrode group.

  In a plan view, the fine wire electrode 502, the fine wire electrode 503, the fine wire electrode 504, and the fine wire electrode 505 are periodically arranged in order. The first thin wire electrode group, the second thin wire electrode group, the third thin wire electrode group, and the fourth thin wire electrode group are arranged substantially in parallel while being displaced in the thickness direction of the base 501. In this embodiment, the thin wire electrode 502, the thin wire electrode 503, the thin wire electrode 504, and the thin wire electrode 505 are provided on a 100 mm square base 501 at a pitch of 5 mm.

  Each thin wire electrode 502 of the first thin wire electrode group is connected to a lead electrode 506 drawn from the surface of the base 501. A part of the extraction electrode 506 extends in the base 501 in a direction substantially orthogonal to the direction in which the thin wire electrodes 502 are arranged, and is connected to each thin wire electrode 502 of the first thin wire electrode group. Further, the remaining portion of the extraction electrode 506 extends from the contact point with any one of the thin wire electrodes 502 in the thickness direction of the base body 501 and protrudes from the surface of the base body 501. The extraction electrode 506 is formed of the same material as the thin wire electrode 502.

  Each thin wire electrode 503 of the second thin wire electrode group is connected to a lead electrode 507 drawn from the surface of the base 501. A part of the extraction electrode 507 extends in the base 501 in a direction substantially orthogonal to the direction in which the thin wire electrodes 503 are arranged, and is connected to each thin wire electrode 503 of the second thin wire electrode group. Further, the remaining portion of the extraction electrode 507 extends from the contact point with any one of the thin wire electrodes 503 in the thickness direction of the base body 501 and protrudes from the surface of the base body 501. The extraction electrode 507 is made of the same material as the thin wire electrode 503.

  Each thin wire electrode 504 of the third thin wire electrode group is connected to a lead electrode 508 drawn from the surface of the base 501. A part of the extraction electrode 508 extends in the base 501 in a direction substantially orthogonal to the direction in which the thin wire electrodes 504 are arranged, and is connected to each thin wire electrode 504 of the third thin wire electrode group. Further, the remaining portion of the extraction electrode 508 extends from the contact point with any one of the thin wire electrodes 504 in the thickness direction of the base body 501 and protrudes from the surface of the base body 501. The extraction electrode 508 is made of the same material as the thin wire electrode 504.

  Each thin wire electrode 505 of the fourth thin wire electrode group is connected to a lead electrode 509 drawn from the surface of the base 501. A part of the extraction electrode 509 extends in the base 501 in a direction substantially orthogonal to the direction in which the thin line electrodes 505 are arranged, and is connected to each thin line electrode 505 of the fourth thin line electrode group. Further, the remaining portion of the extraction electrode 509 extends from the contact point with any one of the thin wire electrodes 505 in the thickness direction of the base body 501 and protrudes from the surface of the base body 501. The extraction electrode 509 is made of the same material as the thin wire electrode 505. The extraction electrodes 506 to 509 are connected to the voltage application device 600.

  FIG. 9 is a circuit diagram showing a configuration of the voltage application device according to the present embodiment. As shown in FIG. 9, the voltage application device 600 according to the present embodiment includes an electric field control unit 410, an AC signal generation device 420, phase inversion devices 430 and 630, a first amplifier 450, a second amplifier 440, and a third amplifier 650. And a fourth amplifier 640.

  The AC signal generator 420 connected to the electric field control unit 410 is connected to the first amplifier 450 via the contact 460. The AC signal generator 420 is connected to the phase inverter 430 and the second amplifier 440 via the contact 460.

  The AC signal generator 420 is connected to the third amplifier 650 through the contact 660. The AC signal generation device 420 is connected to the phase inversion device 630 and the fourth amplifier 640 via the contact 660.

  The first amplifier 450 is connected to the extraction electrode 506 of the electric field curtain panel 500. The second amplifier 440 is connected to the extraction electrode 508 of the electric field curtain panel 500. The third amplifier 650 is connected to the extraction electrode 507 of the electric field curtain panel 500. The fourth amplifier 640 is connected to the extraction electrode 509 of the electric field curtain panel 500.

  From the voltage application device 600, each of the thin wire electrodes 502 of the first thin wire electrode group via the extraction electrode 506, and each of the thin wire electrodes 503 of the second thin wire electrode group via the extraction electrode 507, and the third electrode via the extraction electrode 508. A so-called electric field curtain is formed by applying an alternating voltage to each thin wire electrode 504 of each thin wire electrode group and each thin wire electrode 505 of the fourth thin wire electrode group via the extraction electrode 509.

  Hereinafter, an experimental example in which the substrate 200 is formed in the film forming apparatus according to the second embodiment will be described.

(Experimental example 2)
In the film forming apparatus of this embodiment, the voltage application apparatus 600 applied a voltage having a frequency of 20 kHz and an output voltage of ± 8 kV to the thin wire electrodes 502 to 505. The phase difference of the voltage applied to each of the four thin wire electrodes 502 to 505 was 90 degrees.

  FIG. 10 is a graph showing a result of an experiment in which a film forming process is performed in the film forming apparatus according to the second embodiment. In FIG. 10, the vertical axis indicates the film thickness (nm) of the deposited film, and the horizontal axis indicates the distance (mm) from the substrate end on the exhaust region side. FIG. 10 also shows experimental results of the comparative example shown in FIG. 6 and the film forming apparatus of the first embodiment.

  As shown in FIG. 10, also in the film forming apparatus of the second embodiment, the film thickness of the film forming material 160 formed on the main surface of the substrate 200 is the spray region X, the flow channel region Y, and the exhaust region Z. It becomes thinner in order.

  In the spray region X, the film thickness of the film forming material 160 formed on the main surface of the substrate 200 is the same as the film forming apparatus of the comparative example, the film forming apparatus of the first embodiment, and the film forming apparatus of the second embodiment. There was almost no difference. In the flow path region Y and the exhaust region Z, the film thickness of the film formed in the film forming apparatus according to the second embodiment is larger than that in the film forming apparatus according to the comparative example and the first embodiment.

  This is because the electric field curtain panel 500 in the film forming apparatus of the second embodiment causes more fine particles of the film forming material 160 to move toward the substrate 200 in the flow path region Y and the exhaust region Z, so that the main surface of the substrate 200 is obtained. It is because it was deposited on the top.

  Also in the film forming apparatus of the present embodiment, the fine particles 300 of the film forming material 160 can be prevented from adhering to the facing surface 156. Further, the fine particles 300 of the film forming material 160 can be deposited on the main surface of the substrate 200. Therefore, it is possible to form a high-quality film while reducing the film formation cost by reducing the frequency of maintenance of the film formation apparatus 100 and improving the utilization efficiency of the film formation material 160.

  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 100 Film-forming apparatus, 110 Conveyance mechanism, 111 Conveyance belt, 112 Pulley, 113 Drive shaft, 120 Heating mechanism, 130 Spray nozzle, 140 Tank, 141 Passage, 150 Case, 151 Inlet, 152 Exhaust, 153 Exhaust space, 154 Partition wall, 155 opening, 156 facing surface, 157 opening, 158 spraying mechanism arrangement space, 159 film forming gas spraying space, 160 film forming material, 170 carrier gas, 180 exhaust gas, 181 mixing region, 190,500 electric field curtain Panel, 191 Mounting member, 192, 501 Base, 193, 194, 502-505 Fine electrode, 195, 196, 506-509 Extraction electrode, 200 Substrate, 300 Fine particles, 310 Electric field lines, 320 Electrostatic force, 330 Centrifugal force, 400,600 voltage application device, DESCRIPTION OF SYMBOLS 10 Electric field control part, 420 AC signal generator, 430,630 Phase inversion apparatus, 440 2nd amplifier, 450 1st amplifier, 460,660 Contact, 640 4th amplifier, 650 3rd amplifier, X spraying area, Y flow Road area, Z Exhaust area.

Claims (10)

A film forming apparatus for depositing a fine film forming material on a substrate to form a film,
A housing,
A spraying mechanism for spraying a film forming gas obtained by atomizing the film forming material into the housing;
A film forming apparatus, comprising: an electric field generating mechanism configured to generate an electric field in the vicinity of the predetermined location so that the film forming material does not adhere to the predetermined location on the wall surface of the housing. The housing has an exhaust port for exhausting the film forming gas,
The film-forming gas passes through a flow channel region in which the film-forming gas flows along the substrate from a spraying region where the film-forming gas is sprayed onto the substrate in the casing, Gas flows from above the substrate to the exhaust region toward the exhaust port,
The film forming apparatus according to claim 1, wherein the predetermined location is a wall surface of the housing located in the flow path region. A transport mechanism for transporting the substrate so as to sequentially pass through the spray region, the flow channel region, and the exhaust region;
The film forming apparatus according to claim 1, further comprising a heating mechanism that heats the substrate from a main surface side opposite to a main surface on which the film forming material is deposited.   4. The film forming apparatus according to claim 1, wherein the electric field generating mechanism includes a base made of an insulator and a thin wire electrode made of a metal provided in the base.   The film forming apparatus according to claim 4, wherein the insulator is ceramic.   The film forming apparatus according to claim 4, wherein the metal is tungsten.   The film-forming apparatus in any one of Claim 4 to 6 with which the said some thin wire electrode was provided substantially parallel.   The film forming apparatus according to claim 4, wherein a voltage of 5 kV to 10 kV is applied to the thin wire electrode. A plurality of fine wire electrode groups consisting of a plurality of the fine wire electrodes are arranged in a plurality of substantially parallel positions shifted in the thickness direction of the substrate,
The film forming apparatus according to claim 7, wherein an AC voltage of 5 kV or more and 10 kV or less is applied to each of the plurality of thin wire electrode groups independently of each other. A plurality of fine wire electrode groups consisting of a plurality of the fine wire electrodes are arranged in a plurality of substantially parallel positions shifted in the thickness direction of the substrate,
The film forming apparatus according to claim 7, wherein an AC pulse voltage of 5 kV or more and 10 kV or less is applied to each of the plurality of thin wire electrode groups independently of each other.

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