JP6204846B2 - Powder feeder, film forming apparatus, and film forming method - Google Patents

Description

  The present invention relates to a powder feeder, a film forming apparatus, and a film forming method using them.

  For example, as a method of forming a film-like element structure on a substrate when manufacturing various electronic components such as a photoelectrode used for a solar cell, an aerosol deposition method (hereinafter sometimes referred to as an AD method). May be used. In the AD method, powders as raw material particles, particularly nano-sized fine particles, are aerosolized, and then the aerosol is sublimated using a carrier gas composed of an inert gas such as helium, argon, nitrogen, or the like. This is a method of accelerating the sound speed to about supersonic speed and physically spraying it on the substrate. Accordingly, the AD method is an impact consolidation phenomenon, and a thin film can be formed on the substrate at a low temperature condition and at a high film formation speed by bonding the fine particles and the substrate or the fine particles. Since such AD method enables film formation at room temperature and there are few restrictions on the characteristics of the substrate, development of various electronic components that form a thin film using the AD method has been actively conducted. It has come to be.

  As described above, in the AD method, it is indispensable to aerosolize the raw material, but conventionally, by preparing fine particles that can be aerosolized in advance in a container and introducing gas into the container. A method of generating an aerosol has been employed (see, for example, Patent Document 1). However, in the conventional method as described in Patent Document 1, after preparing the fine particles by pulverizing the raw material in advance, the fine particles are transferred into the aerosol generation container and aerosolized, The process is complicated, and there is a possibility that the state of the aerosol may change as the state of aggregation of the fine particles in the container changes.

  In addition, a film forming method and apparatus have been proposed in which a mechanism for containing raw material fine particles and a mechanism for generating aerosol are separated and fine particles are quantitatively supplied from the raw material containing mechanism to the aerosol generating mechanism (for example, Patent Documents). 2). However, the film forming method and apparatus described in Patent Document 2 still has a problem that the process and the apparatus structure become complicated. In addition, when the fine particles are transported from the raw material accommodation mechanism to the aerosol generation mechanism, there is a possibility that the aggregation state of the fine particles may change, and there is a possibility that the state of the aerosol will change with this change. In addition, in the course of transporting the fine particles, the fine particles may clog in the path due to the fine particles adhering to the container or the transport pipe.

International Publication No. 01/27348 JP 2006-200013 A

  The present invention has been made in view of the above problems, and can prevent clogging due to fine particles without complicating the process and the apparatus, and can suppress the reaggregation of fine particles and stably and efficiently prevent aerosols. It is an object of the present invention to provide a powder supply device that can be generated, a film forming apparatus including the powder supply device, and a film forming method using them.

The invention according to claim 1 is a powder feeder, which is a container for storing a raw material, a pulverization unit for preparing fine particles by pulverizing the raw material, and an aerosol for aerosolizing the fine particles. A generation unit, and the storage unit, the crushing unit, and the aerosol generation unit are provided in this order from the lower side to the upper side in the generation container in the same generation container. The crushing part is formed of a rotating body having a plate-like blade having a rectangular shape in plan view, and the blades are bent on opposite sides on both sides in the longitudinal direction of the crushing part. And a structure that generates a swirling flow that rises toward the aerosol generation unit in the generation container, and the raw material is continuously supplied from the storage unit toward the crushing unit. together, the fine particles, the swirling flow More, toward from the crusher to the aerosol generation portion is continuously fed, characterized by sequentially sent toward the aerosol is produced continuously in the aerosol generation portion to outside.
Invention of Claim 2 is a powder feeder of Claim 1, Comprising: The said crushing part consists of a rotary body which has the 2 blade | wing each arrange | positioned at the both sides of the said longitudinal direction, respectively. Features.

  According to the present invention, since the storage unit, the crushing unit and the aerosol generating unit are provided in the same generation container, since the raw material crushing and aerosolization proceed substantially simultaneously in the same process, The process becomes simple. In addition, since the crushing unit and the aerosol generation unit are provided in the same generation container, the device structure is also simplified. Furthermore, since the fine particles can be continuously aerosolized immediately after the raw material is crushed, the means for conveying the fine particles can be omitted, and clogging of the fine particles in the conveying path can be suppressed, The residence time of the fine particles before aerosolization can be shortened, and the fine particles can be prevented from reaggregating. Therefore, it is possible to prevent clogging due to the fine particles without complicating the process and the apparatus, and to suppress the reaggregation of the fine particles and to generate the aerosol stably and efficiently.

In addition, according to the present invention, since the raw material can be pulverized with a stable particle size distribution into fine particles by the pulverization part made of a rotating body, it is possible to generate aerosol more stably and efficiently. It becomes.

Furthermore, according to the present invention, since the crushing part having the above-described structure is rotated to generate an air flow that is an upward swirling flow toward the aerosol generating part, the fine particles prepared by the crushing part are immediately generated in the generation container. It is possible to effectively float the fine particles again.

Wherein the invention is claimed in claim 3, a powder supply device according to claim 1 or claim 2, wherein the crusher is, the rotational speed of the rotating body is in a range of 1000~30000rpm And
According to the present invention, by setting the number of rotations of the rotating body within an appropriate range, first, the raw material can be efficiently crushed and prepared as fine particles, and the adjusted fine particles can immediately float in the production container. Therefore, the aerosol can be stably and efficiently generated while the reaggregation of the fine particles is more effectively suppressed.

Invention of Claim 4 is a film-forming apparatus, Comprising: At least 1 or more is provided with the powder supply apparatus as described in any one of Claims 1-3 , and the board | substrate used as film-forming object is accommodated. A film formation chamber, and an injection unit that injects the aerosol introduced from the powder supplier into the film formation chamber toward the substrate.
According to the present invention, since the powder feeder according to the present invention is provided, it is possible to suppress clogging or re-aggregation of fine particles in the apparatus, and to produce a thin film having excellent characteristics on the substrate. It becomes possible to form a film with good properties.

A fifth aspect of the present invention is the film forming apparatus according to the fourth aspect , comprising a plurality of the powder feeders, and aerosols having different particle size distributions are generated in the plurality of powder feeders. And is introduced into the film forming chamber.
According to the present invention, a plurality of types of aerosols having different particle size distributions are introduced into the film forming chamber. Therefore, the particle size distribution in the thin film formed on the substrate can be arbitrarily determined by adjusting the fraction of each aerosol. It becomes possible to adjust to.

Invention of Claim 6 is a film-forming method, Comprising: The powder feeder as described in any one of Claims 1-3 , or the film-forming of Claim 4 or Claim 5 A thin film is formed on a substrate using the apparatus.
According to the present invention, since the thin film is formed on the substrate using the above-described powder feeder or film forming apparatus, it is possible to form a thin film having excellent characteristics with high productivity.

According to the powder feeder, the film forming apparatus including the powder feeder, and the film forming method using the powder feeder according to the present invention, the following effects can be achieved by the above-described solving means.
That is, according to the powder feeder according to the present invention, since the storage unit, the crushing unit, and the aerosol generating unit are provided in the same generation container, the raw material crushing and the aerosolization are almost the same in the same process. Since the process proceeds continuously at the same time, the process and the apparatus structure are simplified. Furthermore, since the fine particles can be continuously aerosolized immediately after the raw material is crushed, the means for conveying the fine particles can be omitted, the clogging of the fine particles in the conveying path can be suppressed, and the fine particles before aerosolization can be removed. The storage time can be shortened and the fine particles can be prevented from reaggregating.
Therefore, it is possible to prevent clogging due to the fine particles without complicating the process and the apparatus, and it is possible to suppress the reaggregation of the fine particles and to generate the aerosol stably and efficiently.

  Moreover, according to the film forming apparatus of the present invention, since the above-described powder feeder is provided, it is possible to suppress clogging or re-aggregation of fine particles in the apparatus and to have excellent characteristics on the substrate. There is an effect that the thin film can be formed with high productivity.

  In addition, according to the film forming method of the present invention, since a thin film is formed on a substrate using the above powder feeder or film forming apparatus, a thin film having excellent characteristics can be formed with high productivity. Has the effect of becoming.

It is a schematic cross section explaining the powder feeder which is one Embodiment of this invention. It is a schematic diagram explaining the powder feeder which is one Embodiment of this invention, and is a perspective view which shows an example of the rotary body used for a crushing part. It is a figure explaining the film-forming apparatus which is one Embodiment of this invention, and is a schematic block diagram which shows an example of the film-forming apparatus to which the powder feeder shown in FIG. 1 is applied. It is a schematic cross section explaining the powder feeder of the conventional structure which is a comparative example.

  Hereinafter, referring to the drawings, an embodiment of a powder feeder according to the present invention, a film forming apparatus provided with the powder feeder, and a film forming method using them will be described with reference to FIGS. The configuration will be described with reference to FIG. Note that the drawings used in the following description may show the characteristic parts in an enlarged manner for the sake of convenience in order to make the characteristics easy to understand. There is. In addition, the materials, dimensions, and the like exemplified in the following description are examples, and the present invention is not limited to them, and can be appropriately changed and implemented without changing the gist thereof.

[Powder feeder]
FIG. 1 is a schematic cross-sectional view showing a powder feeder 1 according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a rotating body that is a crushing unit 3 used in the powder feeder 1. is there.
As shown in FIG. 1, the powder feeder 1 of the present embodiment includes an accommodating portion 2 that accommodates a raw material 6, and a crushing portion (rotating body) 3 that crushes the raw material 6 to prepare fine particles 61. And the aerosol generation unit 4 that generates aerosol 62 by aerosolizing the fine particles 61. The powder feeder 1 has a container 2, a crushing unit 3, and an aerosol generating unit 4 provided in this order from the lower side to the upper side in the same generating container 5, and is schematically configured. In the powder feeder 1, the raw material 6 is continuously supplied from the container 2 to the crushing unit 3, and the fine particles 61 are continuously supplied from the crushing unit 3 to the aerosol generating unit 4. The aerosol 62 continuously supplied and continuously generated by the aerosol generator 4 is sequentially sent out.

As described above, the generation container 5 serving as the casing of the powder supply device 1 of the present embodiment includes the storage unit 2, the crushing unit 3, and the aerosol generation unit 4 in the same space, and the aerosol 62 is continuously provided. For example, it is formed in a substantially cylindrical shape in consideration of stabilization of the airflow in the container when the fine particles 61 are aerosolized.
Further, in the example shown in FIG. 1, the production container 5 is provided with two powder transport gas introduction ports, specifically, a lower introduction port 51 and an upper introduction port 52. In the upper part, a delivery port 53 for delivering the generated aerosol 62 to the outside is provided.

As described above, the storage unit 2 is provided at the lowermost part of the generation container 5 that is also a casing of the powder supply device 1 and stores the raw material 6 that is a raw material of fine particles. Below the crushing unit 3 made of a body, it is arranged at the bottom of the production container 5.
As shown in the illustrated example, the storage unit 2 of the present embodiment is configured to communicate in the same space as the crushing unit 3 and the aerosol generation unit 4 disposed above the generation container 5.

  The means for loading the raw material 6 into the container 2 is not particularly limited and detailed illustration is omitted. For example, a lid is provided on the top of the production container 5 or the production container 5 The raw material 6 can be loaded into the container 2 by dividing the upper and lower portions at any position in the vertical direction so that the container can be opened and closed.

The crushing unit 3 includes a crushing mechanism that crushes the raw material 6 to prepare the fine particles 61. In the example described in the present embodiment, the crushing unit 3 includes a rotating body as illustrated in FIG.
The crushing part 3 shown in FIG. 2 is comprised as a rotary body which has a plate-shaped 2 blade | wing with substantially rectangular shape in planar view. The crushing part 3 has an attachment hole 3a for attaching the crushing part 3 to the rotating shaft 3A shown in FIG. In addition, blades 31 and 32 for crushing the raw material 6 are formed on both sides of the crushing part 3 with the attachment hole 3a interposed therebetween. Moreover, in the example of illustration, the blade | wing 31 and the blade | wing 32 are formed in the substantially square shape so that it may be bent in the reverse surface side in the crushing part 3 made into plate shape, respectively.
A rotating shaft 3 </ b> A shown in FIG. 1 rotates the crushing unit 3 by being rotated by a motor (not shown) provided outside the generation container 5.

  Since the crushing part 3 made of a rotating body is for crushing the raw material 6 into powder, it is preferable to have a shape used in a mill or the like. Specifically, FIG. It preferably has a shape as illustrated.

  Moreover, the crushing part 3 is made into the said shape, and while crushing the raw material 6, it produces an airflow by the upward swirling flow, and the fine particle 61 after crushing is carried on the airflow and floats up. It is configured as a so-called Henschel mixer (registered trademark), which is a rotating body capable of operating. As described above, in the present embodiment, the crushing unit 3 is configured as a rotating body, thereby generating an air flow that is an upward swirling flow toward the upper side in the generation container 5, that is, the aerosol generation unit 4 side. It is preferable to adopt a structure to be used. Thereby, the fine particles 61 prepared by the crushing unit 3 can be immediately levitated to the aerosol generating unit 4 side in the generation container 5, and the reaggregation of the fine particles 61 can be effectively suppressed.

  Further, in the vicinity of the crushing unit 3, a lower introduction port 51 into which the powder transport gas is taken is disposed so as to open in a part of the side surface of the generation container 5. The fine particles 61 prepared in the crushing unit 3 are formed into an aerosol generating unit by the air current generated by the powder transport gas introduced from the lower introduction port 51 and the upward swirling flow accompanying the rotation of the crushing unit 3 as described above. It is levitated toward the 4th side.

  The crushing unit 3 of the present embodiment can crush the raw material 6 with a stable particle size distribution into the fine particles 61 by the crushing unit 3 composed of a rotating body having the above-described configuration. 4, it becomes possible to generate aerosol more stably and efficiently.

  In addition, the crushing part 3 used by this embodiment is not limited to the thing of the shape shown in FIG. 2, For example, it is using a propeller-shaped rotary body and the number of propellers is about 2-4. Further, it is more preferable from the viewpoint that the crushing efficiency of the raw material 6 and the stability of the particle size distribution, and further, the fine particles 61 after crushing can be continuously levitated toward the aerosol generating unit 4.

  Moreover, it is preferable that the crushing part 3 consists of material of hardness higher than the raw material 6, for example, it is more preferable that Mohs hardness is 6 or more. Examples of the material having such hardness include various metal materials such as stainless steel (SUS), titanium, tungsten, silicon carbide, and aluminum oxide, and these metal materials can be used in the crushing portion 3 without any limitation. Can be used.

  Moreover, the rotation speed of the crushing part 3 at the time of crushing the raw material 6 to prepare the fine particles 61 is not particularly limited, but is preferably in the range of 1000 to 30000 rpm, for example. Thus, by making the rotation speed of the crushing part 3 made of a rotating body into an appropriate range, the raw material 6 can be efficiently crushed and prepared as fine particles 61, and the adjusted fine particles 61 are immediately produced in the production container 5. It is possible to float toward the aerosol generation unit 4 inside. Accordingly, it is possible to more stably and efficiently generate the aerosol 62 in the aerosol generation unit 4 to be described later while suppressing the reaggregation of the fine particles 61 more effectively.

  The aerosol generation unit 4 generates aerosol 62 by aerosolizing the fine particles 61 prepared in the crushing unit 3 with a powder transport gas introduced into the generation container 5. Specifically, the fine particles 61 that float on the aerosol generating unit 4 by riding on the air flow caused by the rotational force of the crushing unit 3 and the powder transport gas introduced from the lower introduction port 51 are introduced into the powder introduced from the lower introduction port 51. It is dispersed and aerosolized in the body transport gas and the powder transport gas introduced from the upper inlet 52 of the production container 5.

When the aerosol generation unit 4 aerosolizes the fine particles 61 to form the aerosol 62, the generation efficiency depends on the flow rate of the powder transport gas introduced into the aerosol generation unit 4 and the like.
In the powder feeder 1 shown in FIG. 1, first, a powder transport gas having a relatively small flow rate is introduced from a lower inlet 51 provided at the lower portion of the production container 5, and is generated by the rotation of the crushing unit 3. The fine particles 61 are levitated to the position of the aerosol generating unit 4 by adding an air flow by the powder transport gas to the air flow.
Furthermore, by introducing a powder transport gas having a large flow rate from an upper introduction port 52 provided at the upper part of the generation container 5, the aerosol generation unit 4 converts the fine particles 61 into an aerosol, and the generated aerosol 62 is removed from the outside. To send. More specifically, the aerosol 62 is directed from the delivery port 53 provided at the uppermost part of the production container 5 toward the injection unit 19 installed in the film forming chamber 11 of the film forming apparatus 10 as shown in FIG. Transport.

  In addition, in the powder feeder 1 of the example shown in FIG. 1 (and FIG. 3), the lower inlet 51 and the upper inlet 52 described above are provided as the inlets for the powder carrier gas. It is not limited to. For example, if it is necessary to provide a powder transport gas inlet at the top of the production container for the convenience of the device design, the upper and lower parts of the production container will be Although it is preferable to provide introduction ports at two locations, a configuration in which only one introduction port is provided by optimizing the arrangement of the introduction ports in the generation container may be employed.

  Further, the outlet 53 is preferably provided in the vicinity of the aerosol generating unit 4 and on the upper side of the generation container 5 as much as possible in order to efficiently send the generated aerosol 62 to the outside.

  Below, the outline of the process which produces | generates the aerosol 62 using the powder feeder 1 of the said structure is demonstrated. In addition, about each process including the production | generation of the aerosol 62 at the time of applying the powder supply apparatus 1 of this embodiment to the film-forming apparatus 10 shown in FIG. 3, in description of the film-forming apparatus and film-forming method mentioned later. Detailed description.

A powder transport gas made of, for example, nitrogen is introduced into the powder feeder 1 from a gas cylinder provided outside (see the gas cylinder 16 in FIG. 3) into the lower inlet 51 and the upper inlet 52. The In addition, the raw material 6 is loaded in the storage unit 2 in advance before the powder feeder 1 is operated.
The raw material 6 loaded in the storage unit 2 is crushed and prepared into fine particles 61 by the rotation operation of the crushing unit 3 disposed immediately above the storage unit 2. At this time, the raw material 6 is continuously supplied toward the crushing unit 3, and the crushing unit 3 continuously prepares the fine particles 61.

The fine particles 61 prepared in the crushing unit 3 float up to the aerosol generating unit 4 by the air current of the powder transport gas introduced from the lower introduction port 51 and the upward swirling flow accompanying the rotation of the crushing unit 3.
In the aerosol generation unit 4, the powder transport gas is introduced from the upper introduction port 52, and the fine particles 61 are dispersed in the powder transport gas introduced from the lower introduction port 51 and the upper introduction port 52. Aerosolized to produce aerosol 62.
The aerosol 62 is sent to the outside from a delivery port 53 disposed in the vicinity of the aerosol generation unit 4 and at the top of the generation container 5, and specifically, the formation of the film forming apparatus 10 shown in FIG. It is sent out toward the injection unit 19 provided in the membrane chamber 11.

  In the present embodiment, in order to effectively float the fine particles 61 prepared in the crushing unit 3 toward the aerosol generating unit 4, it is preferable to appropriately control the ascending airflow. Thus, as means for controlling the air flow inside the production container 5, for example, the “height dimension of the production container 5”, “the flow rate of the powder transport gas”, and “the rotational speed of the crushing unit 3” Appropriate adjustment of each as a control factor

  Further, in the present embodiment, with respect to the loading of the raw material 6 into the storage unit 2, a lid is provided on the upper part of the production container 5, or the production container 5 is divided into upper and lower parts so as to be openable and closable. In this case, it is necessary to open and close the production container 5 and to fill the raw material 6 every time the raw material 6 in the container 2 is used up. For this reason, in this embodiment, as a structure for loading the raw material 6 into the storage unit 2, for example, the height dimension of the storage unit 2 in the generation container 5 is configured to be large, and the crushing unit 3 is used as the generation container. The structure which can move in the height direction in 5 and can make the height position of the crushing part 3 low can be employ | adopted as the raw material 6 is crushed. In such a configuration, the amount of the raw material 6 that can be loaded in the storage unit 2 is increased, so that the period in which the raw material 6 needs to be loaded can be lengthened.

  Here, as described above, when the fine particles 61 are levitated almost simultaneously with the crushing of the raw material 6, the large and small particles are levitated to the aerosol generating unit 4 at the same time, and the generated aerosol 62 is generated. There may also be a range in the particle size distribution. In the present embodiment, for example, by appropriately adjusting the height of the generation container 5, a classification function can be provided using a difference in flying height due to the size of the particle size of the fine particles 61, or a manufacturing apparatus described later. As described below, by providing a classification unit at the subsequent stage of the powder supplier 1, a means for suppressing the particle size distribution of the aerosol 62 to an appropriate range can be employed.

According to the powder feeder 1 of the present embodiment, with the above-described configuration, the crushing and aerosolization of the raw material 6 proceed continuously and substantially simultaneously in the same process, so that the process and the device structure are simplified.
Furthermore, since the fine particles 61 can be aerosolized immediately after the raw material 6 is crushed, the conventional fine particle 61 transport mechanism can be omitted, and the fine particles 61 having a relatively large particle size are clogged in the transport path. Can be suppressed. In addition, the residence time of the fine particles 61 before aerosolization can be shortened and the fine particles 61 can be prevented from reaggregating. Furthermore, adhesion of fine particles in the apparatus can be prevented by the air current of the powder transport gas and the upward swirling flow generated in the crushing unit 3.
Thereby, it is possible to stably and efficiently generate the aerosol 62 while suppressing reaggregation of the fine particles 61.

[Film Forming Apparatus and Film Forming Method]
FIG. 3 is a schematic configuration diagram illustrating a film forming apparatus 10 adopting the aerosol deposition method (AD method) to which the powder supplier 1 described in the present embodiment is applied.
The film forming apparatus 10 of this embodiment includes at least one or more powder feeders 1 having the above-described configuration, accommodates a substrate 41 to be formed, and forms a thin film (not shown) on one surface 41a. The film forming chamber 11 and the spray unit 19 that sprays the aerosol 62 introduced from the powder supplier 1 into the film forming chamber toward the substrate 41 are provided.

In the film forming chamber 11, a stage 12 having an arrangement surface 12a for arranging the substrate 41 is provided. The stage 12 is movable in the horizontal direction with the substrate 41 disposed.
Further, a vacuum pump 13 is connected to the film forming chamber 11, and the vacuum inside the film forming chamber 11 is made negative by suction of the vacuum pump 13.
In addition, the above-described injection unit 19 is disposed in the film forming chamber 11. The ejection unit 19 is disposed such that the opening of the discharge port 19a faces the arrangement surface 12a of the stage 12, that is, one surface 41a of the substrate 41 arranged on the arrangement surface 12a of the stage 12. .

The injection unit 19 is connected to the gas cylinder 16 via the transport pipe 15.
A mass flow controller 17 and a powder feeder 1 are provided in the order of the transport pipe 15 from the gas cylinder 16 side. In the illustrated example, a classifier 18 is provided between the powder feeder 1 and the injection unit 19. These transport pipe 15, gas cylinder 16, mass flow controller 17, powder feeder 1, and classifier 18 constitute a powder transport mechanism.

  In the film forming apparatus 10, for example, nitrogen as a transport gas is supplied from the gas cylinder 16 to the transport pipe 15, and the flow rate of the nitrogen is adjusted by the mass flow controller 17. Nitrogen adjusted by the mass flow controller 17 is introduced into the powder feeder 1 by two transport pipes 15. At this time, the flow rate of nitrogen introduced into the powder supplier 1 is not particularly limited, and can be determined in consideration of the injection speed from the injection unit 19 in the film forming chamber 11. In the present embodiment, nitrogen is introduced into the lower inlet 51 of the powder feeder 1 at a flow rate sufficient to generate an air flow sufficient to wind up the fine particles 61, for example, about 0.5 (L / min). At the same time, from the upper inlet 52, fine particles 61 are effectively dispersed in the powder transport gas to be aerosolized, and nitrogen is introduced at a flow rate that can be sent from the outlet 53 at a high speed, for example, about 5 (L / min). It can be a condition to do.

For example, the raw material 6 is loaded into the powder feeder 1 by, for example, opening a lid (not shown) provided in the powder feeder 1 and placing the raw material in the container 2 disposed at the bottom of the production container 5. It is performed by accommodating 6.
The raw material 6 loaded in the storage unit 2 is crushed by the crushing unit 3 made of a rotating body and prepared as fine particles 61, and the rotational force of the crushing unit 3 and the lower introduction port 51 enter the storage unit 2. Due to the airflow of the introduced powder transport gas, the powder rises up to the aerosol generation unit 4 disposed above in the generation container 5.
The fine particles 61 introduced into the aerosol generation unit 4 are aerosolized by being dispersed in the powder transport gas introduced into the aerosol generation unit 4 from the lower introduction port 51 and the upper introduction port 52, and are sent out as an aerosol 62. 53 is conveyed toward the injection unit 19 installed in the film forming chamber 11 through the transport pipe 15. In the example shown in FIG. 3, a classifier 18 is provided on the path of the transport pipe 15 between the powder supplier 1 and the injection unit 19.
Then, the aerosol 62 (fine particles 61) is ejected and ejected from the ejection unit 19 toward the one surface 41a of the substrate 41 at a subsonic to supersonic ejection speed.

  In addition, although it does not specifically limit as transport gas, For example, it is preferable to use oxygen, nitrogen, a noble gas, air (atmosphere), etc.

  Since the film forming apparatus 10 of the present embodiment has the above-described powder supply device 1, clogging, reaggregation, and the like of the fine particles 61 are suppressed in the apparatus, and the characteristics are improved on the substrate 41. An excellent thin film can be formed with high productivity.

  Although detailed illustration is omitted in the film forming apparatus of the present embodiment, for example, a plurality of powder feeders 1 are provided, and each of the plurality of powder feeders 1 has a different particle size distribution. An aerosol 62 (fine particles 61) having different average particle diameters may be generated and introduced into the film forming chamber 11, respectively. Thus, by adopting a configuration in which a plurality of types of aerosols 62 having different particle size distributions are introduced into the film forming chamber 11, for example, a thin film formed on the substrate 41 by adjusting the fraction of each aerosol 62. It is possible to arbitrarily adjust the particle size distribution inside. In addition to arbitrarily preparing the particle size distribution, for example, different types of powders (fine particles) can be sprayed onto the substrate 41, and variations of the obtained thin film can be changed.

  Next, the details of the film forming method when using the film forming apparatus 10 to which the powder feeder 1 of the present embodiment is applied will be described. Hereinafter, a method of forming a photoelectrode of a dye-sensitized solar cell (hereinafter simply referred to as a solar cell) will be described as an example of forming a thin film by the AD method using the film forming apparatus 10.

  In this film forming method, the fine particles 61 of the raw material 6 which is an inorganic substance are aerosolized, and the obtained aerosol 62 is sprayed on the substrate 41 to bond the substrate 41 and the fine particles 61 and to bond the fine particles 61 together. As a result, a thin film of an inorganic substance is formed on the substrate 41.

First, the substrate 41 is placed on the placement surface 12 a of the stage 12 in the film forming chamber 11.
The substrate 41 is not particularly limited, and examples thereof include a transparent substrate used for various electronic components such as a photoelectrode used for a solar cell. Examples of the transparent substrate include a substrate made of glass or plastic, or a film. Examples of the glass that is a material of the substrate 41 include general glasses such as soda lime glass, borosilicate glass, quartz glass, borosilicate glass, Vycor glass, alkali-free glass, blue plate glass, and white plate glass.

  Examples of the plastic that is the material of the substrate 41 include polyacrylic resin, polycarbonate resin, polyester resin, polyimide resin, polystyrene resin, polyvinyl chloride resin, and polyamide resin. Among these, a polyester resin, particularly polyethylene naphthalate (PEN) is preferable from the viewpoint of availability and the like because it is produced and used in large quantities as a transparent heat-resistant film. Furthermore, it is more preferable to use a polyethylene terephthalate (PET) film as the substrate 41 from the viewpoint of manufacturing a thin, light and flexible dye-sensitized solar cell.

Next, the vacuum pump 13 is operated to evacuate the film forming chamber 11.
Next, nitrogen is supplied from the gas cylinder 16 into the film forming chamber 11 through the transport pipe 15 to make the inside of the film forming chamber 11 a nitrogen atmosphere.

  Subsequently, tin-doped indium oxide (ITO), fluorine-doped tin oxide (FTO), zinc oxide (ZnO), tin oxide, antimony-doped tin oxide (ATO), indium oxide / zinc oxide (IZO), gallium oxide / zinc oxide (GZO) The transparent conductive layer made of a conductive material is formed on one surface 41a of the substrate 41 using raw material particles such as Or you may use the board | substrate 41 in which the transparent conductive layer which consists of said electrically conductive material previously was formed.

Next, a photoelectric conversion layer made of a metal oxide such as titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ) is formed on the transparent conductive layer formed on one surface 41 a of the substrate 41. To do. In order to form the photoelectric conversion layer, first, a raw material 6 made of a metal oxide such as titanium oxide, zinc oxide, tin oxide or the like is loaded into the container 2 of the powder feeder 1.
Next, fine particles 61 are prepared by crushing the raw material 6 by the crushing unit 3, and the rotational force of the crushing unit 3 and the air flow of the powder transport gas introduced into the storage unit 2 from the lower inlet 51. Then, the fine particles 61 are floated up to the aerosol generating unit 4. At this time, the fine particles 61 are dispersed and aerosolized in the powder transport gas introduced into the aerosol generating unit 4 from the lower introduction port 51 and the upper introduction port 52. Thereafter, the generated aerosol 62 is sent out from the delivery port 53 to the transport pipe 15, and conveyed to the injection unit 19 installed in the film forming chamber 11 through the classifier 18.
The aerosol 62 is applied from the discharge port 19a of the ejection unit 19 to the surface of the transparent conductive layer formed on the one surface 41a of the substrate 41 (the surface opposite to the surface in contact with the substrate 41 of the transparent conductive layer). Spray (fine particles 61).

  Here, at least a part of the fine particles that collide with the surface of the transparent conductive layer formed on the substrate 41 bite into the surface of the transparent conductive layer and are not easily peeled off. In addition, due to this collision, a new surface is formed on the surface of the transparent conductive layer and the surface of the fine particles, and the transparent conductive layer and the fine particles 61 are mainly joined on the new surface. Subsequently, by further spraying, another fine particle collides with the fine particle that has digged into the surface of the transparent conductive layer. By such collision of the fine particles, a new surface is formed on the surface of the fine particles, and the fine particles are joined mainly on the new surface. In the collision between the fine particles, a temperature rise that causes the fine particles to melt hardly occurs, and therefore, a grain boundary layer made of vitreous does not substantially exist at the interface where the fine particles are joined. Furthermore, by continuing to spray fine particles, a thin film is formed in which a large number of fine particles 61 are gradually bonded to the surface of the transparent conductive layer formed on the substrate 41. Since the formed thin film has sufficient strength as the transparent conductive layer of the dye-sensitized solar cell, baking by baking is not necessary.

According to the film formation method exemplified above, TiO ₂ particles are sprayed at a high speed on the surface of the transparent conductive layer formed on the one surface 41a of the substrate 41 to join the transparent conductive layer and the TiO ₂ particles, By bonding TiO ₂ particles together, a thin film made of TiO ₂ particles can be formed on the transparent conductive layer.
Further, unlike the so-called green compact, the thin film obtained by the above procedure has a stronger strength than the green compact, and is more difficult to peel from the substrate than the green compact.

  Since the film forming method of the present embodiment described above is a method of forming a thin film on the substrate 41 using the powder feeder 1 or the film forming apparatus 10 described above, a thin film having excellent characteristics can be formed with high productivity. Is possible.

[Function and effect]
As described above, according to the powder feeder 1 according to the present invention, the film forming apparatus 10 provided with the powder feeder 1, and the film forming method using them, the following configuration is used. The effect of.
That is, according to the powder feeder 1 according to the present invention, since the container 2, the crushing unit 3, and the aerosol generating unit 4 are provided in the same generating container 5, the raw material crushing and aerosolization can be performed. Since the process proceeds continuously at the same time in the same process, the process and the apparatus structure are simplified. Furthermore, since the fine particles 61 can be aerosolized immediately after the raw material 6 is crushed, the conveyance mechanism of the fine particles 61 can be omitted, the clogging of the fine particles 61 in the conveyance path can be suppressed, and the fine particles 61 before aerosolization can be prevented. The residence time can be shortened, and the fine particles 61 can be prevented from reaggregating.
Therefore, it is possible to prevent clogging with the fine particles 61 without complicating the process and the apparatus, and to suppress the reaggregation of the fine particles 61 and to generate the aerosol stably and efficiently. Play.

  Further, according to the film forming apparatus 10 according to the present invention, since the powder feeder 1 is provided, it is possible to suppress clogging or re-aggregation of the fine particles 61 in the apparatus, and There is an effect that a thin film having excellent characteristics can be formed with high productivity.

  In addition, according to the film forming method of the present invention, since the thin film is formed on the substrate using the powder feeder 1 or the film forming apparatus 10 described above, a thin film having excellent characteristics can be formed with high productivity. There is an effect that becomes possible.

  Next, the present invention will be described in detail by the following examples, but the present invention is not limited only to these examples.

[Example]
In the present embodiment, first, as shown in FIG. 1, the accommodating portion 2 that accommodates the raw material 6, the crushing portion 3 that includes a rotating body that crushes the raw material 6 to prepare the fine particles 61, and the fine particles 61. The powder supply device 1 having a configuration in which the aerosol generation unit 4 that generates the aerosol 62 by being aerosolized is provided in the same generation container 5 was prepared. Here, the crushing part 3 has a shape used as a mill as shown in FIG. 2 and a shape capable of generating a swirling flow. A rotating body having a large size of 10 mm was used.

Next, as the raw material 6, 0.02 kg of titanium oxide (TiO ₂ ) powder was loaded into the container 2, that is, the bottom of the production container 5.
Next, using nitrogen as the powder transport gas, while introducing nitrogen at 0.5 (L / min) from the lower inlet 51 provided in the production vessel 5 and 5 (L / min) from the upper inlet 52 The crushing unit 3 was rotated at 20000 rpm. Thus, while the raw material 6 was continuously crushed to prepare the fine particles 61, the fine particles 61 were continuously dispersed in the powder transport gas in the aerosol generation unit 4 to be aerosolized.

[Comparative example]
In the comparative example, first, as shown in FIG. 4A, the raw material 6 made of titanium oxide powder was crushed in a mortar (not shown) using a mill bar 101 to prepare fine particles 61.
Next, as shown in FIG. 4 (b), using a powder feeder having a conventional configuration in which the gas introduction pipe 103 and the delivery pipe 104 are introduced into the production container 102, the powder is obtained by crushing in a mortar. The obtained fine particles 61 were loaded on the bottom of the production container 102.
Then, nitrogen was introduced at 5 (L / min) as a powder transport gas from the gas introduction pipe 103 into the generation container 102 and aerosolized to generate an aerosol 62.

[Evaluation items and methods]
(Evaluation of aerosol particle size distribution)
The particle size distribution was measured for the aerosols obtained in Examples and Comparative Examples of the above procedure. At this time, the particle size distribution was measured with a laser diffraction particle size distribution measuring apparatus in a state where powders (fine particles) after aerosolization were collected and dispersed in ethanol.

(Evaluation of film formability by ejection and spraying)
The aerosols obtained in each of the examples and comparative examples of the above procedure are introduced into the spray unit 19 provided in the film forming chamber 11 of the film forming apparatus 10 as shown in FIG. 2, and aerosol deposition under the following conditions is performed. A thin film was actually formed by discharging and spraying the substrate 41 by the method (AD method), and the film forming property was evaluated.
At this time, the distance from the injection unit 19 to the substrate 41 was set to 10 mm, and the aerosol 62 was sprayed onto one surface 41a of the substrate 41 to form a thin film.

  More specifically, the aerosol 62 with respect to the substrate 41 under the conditions of the atmospheric pressure in the film forming chamber 11: 100 Pa, the supply amount of the powder transport gas (nitrogen): 5 L / min, and the sweep speed of the substrate 41: 30 cm / min. The film forming process was performed once, and the film forming property was evaluated. At this time, the film formability was evaluated by measuring the film thickness of the formed thin film and observing the appearance with an optical microscope.

[Evaluation results]
As a result of the evaluation tests as described above, in the examples and comparative examples, as shown in Table 1 below, the particle size distribution of the generated aerosol is almost the same, and both show good film formability. confirmed.

  Furthermore, in the embodiment according to the present invention, the raw material 6 is crushed and the fine particles 61 are immediately aerosolized, so that there is no clogging of the powder in the accommodating portion and the piping, and the productivity is excellent. I was able to confirm.

  The configurations and combinations thereof in the embodiments and examples described above are examples, and additions, omissions, substitutions, and other modifications of the configurations can be made without departing from the spirit of the present invention. Moreover, this invention is not limited by each embodiment and an Example, It is limited only by a claim.

  A powder supply device according to the present invention, a film forming apparatus including the powder supply device, and a film forming method using the same include, for example, an element formed on a substrate using an aerosol deposition method. The present invention can be widely applied in the manufacturing process of various electronic parts forming the structure.

DESCRIPTION OF SYMBOLS 1 ... Powder feeder, 2 ... Accommodating part, 3 ... Crushing part (rotating body), 3a ... Mounting hole, 31, 32 ... Blade | wing, 3A ... Rotating shaft, 4 ... Aerosol production | generation part, 5 ... Production container, 51 DESCRIPTION OF SYMBOLS ... Lower inlet, 52 ... Upper inlet, 53 ... Outlet, 6 ... Raw material, 61 ... Fine particle, 62 ... Aerosol, 10 ... Film forming apparatus, 11 ... Film forming chamber, 12 ... Stage, 12a ... Arrangement surface, DESCRIPTION OF SYMBOLS 13 ... Vacuum pump, 15 ... Transport pipe, 16 ... Gas cylinder, 17 ... Mass flow controller, 18 ... Classification part, 19 ... Injection part, 19a ... Discharge port, 41 ... Substrate, 41a ... One side.

Claims (6)

A storage section for storing raw materials,
A crushing section for crushing the raw material to prepare fine particles;
An aerosol generating unit that aerosolizes the fine particles,
The storage unit, the crushing unit and the aerosol generation unit are provided in this order from the lower side to the upper side in the generation container in the same generation container,
The crushing part is made of a rotating body having a plate-like blade having a rectangular shape in plan view, and the blades are each bent in the opposite direction on both sides in the longitudinal direction of the crushing part, It is configured to generate a swirling flow that rises toward the aerosol generation unit in the generation container,
The raw material is continuously supplied from the container to the crushing unit, and the fine particles are continuously supplied from the crushing unit to the aerosol generating unit by the swirl flow. A powder feeder, wherein the aerosol continuously generated by the aerosol generator is sequentially sent out. 2. The powder feeder according to claim 1, wherein the crushing unit includes a rotating body having two blades arranged on both sides in the longitudinal direction. The powder crusher according to claim 1 or 2 , wherein the crushing unit has a rotating speed of the rotating body in a range of 1000 to 30000 rpm. Comprising at least one powder feeder according to any one of claims 1 to 3 ,
A film formation chamber for accommodating a substrate to be formed; and
A film forming apparatus, comprising: an injection unit configured to inject the aerosol introduced into the film formation chamber from the powder feeder toward the substrate. The film forming apparatus according to claim 4 , comprising a plurality of the powder supply devices, wherein aerosols having different particle size distributions are generated in the plurality of powder supply devices and introduced into the film forming chamber. apparatus. Powder supplying device according to any one of claims 1 to 3, or by using a film forming apparatus according to claim 4 or claim 5, characterized in that depositing a thin film on a substrate A film forming method.

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