JP7503398B2 - Vacuum deposition equipment parts - Google Patents

Description

The present invention relates to a part for a vacuum film-forming device that exists in a vacuum chamber and that forms an organic film by adhering and depositing organic molecules on a surface of an object to be film-formed, when an organic material is vaporized or sublimated in a vacuum chamber in a vacuum atmosphere and the vaporized or sublimated organic molecules are attached and deposited on the surface of the object to be film-formed.

Conventionally, a vacuum film-forming apparatus for forming an organic film by a vacuum deposition method on a film-forming target object (hereinafter referred to as a "substrate") such as a glass substrate or a sheet-shaped resin substrate having a predetermined contour is known, for example from Patent Document 1. This apparatus is equipped with a vacuum chamber, and a crucible is disposed at the bottom of the vacuum chamber, which contains an organic material appropriately selected according to the organic film to be formed. The vacuum chamber is then made into a vacuum atmosphere, and the organic material in the crucible is heated and vaporized or sublimated, and the organic molecules scattered from the discharge opening of the crucible according to a predetermined cosine law are attached and deposited on the substrate surface, forming an organic film with a predetermined thickness. At this time, the vaporized or sublimated organic molecules are also attached and deposited on the surfaces of various components, such as an adhesion prevention plate that prevents deposition on the inner wall of the vacuum chamber and a regulation plate (shielding means) that is disposed in the vacuum chamber and regulates the range of scattering of the organic material onto the substrate, thereby forming an organic film. Components such as the adhesion prevention plate and the regulation plate are generally made of metal materials such as stainless steel or aluminum.

Here, it has been found that when forming an organic film as described above, depending on the organic material (i.e., the distribution of the organic material scattered from the crucible), the organic material may adhere and accumulate at specific locations on the component surface, causing the organic film to grow locally (more specifically, to grow in a convex shape in a direction perpendicular to the component surface). In particular, if an organic film grows locally on the component surface located near the discharge opening of the crucible, and this grown organic film blocks the scattering path of organic molecules that are scattered from the discharge opening of the crucible according to a predetermined cosine law, problems arise in that the film formation rate and film thickness distribution are reduced. In such cases, the above-mentioned parts can be replaced frequently, but this makes it impossible to operate the vacuum film formation device continuously for long periods of time.

The inventors of the present application therefore conducted extensive research and discovered the following: In other words, among the organic materials used to form the organic film, many of the organic molecules that are vaporized or sublimated and attached to the surface of a component have a molecular orientation direction that is perpendicular to the surface of the component (normal direction), and they discovered that in the case of such organic molecules, the organic film tends to grow in a relatively short time so as to extend convexly in the normal direction.

Japanese Patent Application Laid-Open No. 7-98862

In view of the above, the present invention aims to provide components for vacuum deposition equipment that can operate continuously for long periods of time.

In order to solve the above problems, when an organic material is vaporized or sublimated from a vapor deposition source in a vacuum chamber in a vacuum atmosphere, and the vaporized or sublimated organic molecules are attached and deposited on the surface of an object to be film-formed to form an organic film, the part for a vacuum film-forming apparatus of the present invention is arranged around the vapor deposition source in the vacuum chamber, and the organic molecules released from the vapor deposition source are directly attached to and deposited on the surface to grow an organic film. The part has a base material and a molecular orientation control film made of Ag or Au formed with a predetermined thickness on the surface of the base material to which the organic molecules are attached , and is configured so that the molecular orientation direction of the organic molecules is oriented in the tangential direction due to the interaction between the d-electron cloud or π-electron cloud spreading on the surface of the molecular orientation control film and the π-electron cloud of the organic molecules attached to the molecular orientation control film, causing the organic film to grow in the tangential direction .

According to the present invention, it has been confirmed that the convex growth of the organic film formed on the surface of the component is suppressed, and the vacuum film forming apparatus can be operated continuously for more than twice as long as the conventional product, when the organic film is formed on the surface of the component without the molecular orientation control film. This is because, even if the molecular orientation direction of the organic molecules is normal when the vaporized or sublimated organic molecules adhere to the surface of the component, if a molecular orientation control film such as Ag, Au, graphite or graphene is present on the surface of the base material (i.e., the surface on which the organic film is formed), the molecular orientation direction of the organic molecules becomes tangential due to the interaction between the d-electron cloud or π-electron cloud spreading on the surface of the molecular orientation control film and the π-electron cloud of the organic molecules attached to the surface, which makes it easier for the organic film to grow in the tangential direction and suppresses the growth of the organic film in the normal direction. In addition, since the organic film formed on the surface of the molecular orientation control film is denser than the conventional product, the generation of particles from the organic film on the surface of the component can be further suppressed, and continuous operation can be extended even longer.

1A is a partial perspective view, partly in cross section, illustrating the configuration of a vacuum deposition apparatus of the present embodiment, and FIG. 1B is a partial cross-sectional view of the vacuum deposition apparatus as viewed from the front side. 1(b) is an enlarged cross-sectional view of the portion indicated by the symbol II surrounded by a dashed line in FIG. 1(b), and a further enlarged schematic diagram of the component surface, in which (a) shows a state in which molecules are vertically oriented in the normal direction on the surface of the base material, (b) shows a state in which molecules are vertically oriented in the tangential direction on the surface of the molecular orientation control film, and (c) shows a state in which molecules are horizontally oriented in the tangential direction on the surface of the molecular orientation control film. 1 is an X-ray diffraction spectrum of an organic film formed in an experiment showing the effect of the present invention.

The following describes an embodiment of the vacuum deposition apparatus, which is a vacuum deposition apparatus Dm, and a component for the vacuum deposition apparatus of the present invention, which exists in a vacuum chamber and on whose surface organic molecules adhere and deposit to form an organic film, is an adhesion prevention plate MP placed in the vacuum chamber, with reference to the drawings. In the following, terms indicating directions such as "upper" and "lower" are explained based on FIG. 1.

1(a) and (b), Dm is a vacuum deposition apparatus equipped with the adhesion prevention plate MP of this embodiment. The vacuum deposition apparatus Dm forms an organic film on the surface of a film-forming object (hereinafter referred to as "substrate Sw") such as a glass substrate by a vacuum deposition method, and is equipped with a vacuum chamber 1. Although not particularly shown or described, a vacuum pump is connected to the vacuum chamber 1 via an exhaust pipe, so that the inside of the vacuum chamber 1 can be evacuated to a predetermined pressure (vacuum level) and maintained. In addition, a substrate transport device 2 is provided on the upper part of the vacuum chamber 1. The substrate transport device 2 has a carrier 21 that holds the substrate Sw with the lower surface as the deposition surface open, and the carrier 21 and thus the substrate Sw can be moved at a predetermined speed in one direction in the vacuum chamber 1 by a driving device not shown. As the substrate transport device 2, a known one can be used, so further description will be omitted. In the following, the relative movement direction of the substrate Sw with respect to the deposition source 5 described later is the X-axis direction, and the width direction of the substrate Sw perpendicular to the X-axis direction is the Y-axis direction.

A plate-shaped mask plate 3 is provided between the substrate Sw transported by the substrate transport device 2 and the deposition source 5 described below. In this embodiment, the mask plate 3 is attached integrally to the substrate Sw and transported by the substrate transport device 2 together with the substrate Sw. The mask plate 3 can also be fixedly disposed in the vacuum chamber 1 in advance. The mask plate 3 has a plurality of openings 31 formed therethrough in the plate thickness direction, and the deposition material is deposited on the substrate Sw in a predetermined pattern by limiting the range of adhesion to the substrate Sw at positions where these openings 31 are not present. The mask plate 3 can be made of metals such as invar, aluminum, alumina, and stainless steel, or resins such as polyimide.

In addition, a plate-shaped anti-adhesion plate MP is arranged inside the vacuum chamber 1 to prevent deposition of a film on the inner wall of the vacuum chamber 1, and constitutes a component of the vacuum deposition device Dm of this embodiment. The anti-adhesion plate MP is made of metal such as stainless steel or aluminum, and is arranged on the bottom surface of the vacuum chamber 1 so as to cover both ends in the Y-axis direction of the deposition source 5 described below. The deposition source 5 is provided on the bottom surface of the vacuum chamber 1, facing the substrate Sw.

The deposition source 5 has a storage box 51 that stores an organic material 6 as a deposition material. The organic material 6 is appropriately selected according to the organic film to be formed on the substrate Sw, and is in the form of granules or tablets. A metal crucible 52 is provided in the storage box 51, and the organic material 6 is filled in the crucible 52. A heating means 53 such as a sheath heater is provided between the crucible 52 and the bottom wall of the storage box 51 so as to cover the entire outer wall surface of the crucible 52. A plurality of (six in this embodiment) emission openings 54 made of a cylinder of a predetermined height are arranged in a row at predetermined intervals in the Y-axis direction on the upper surface 51a of the storage box 51 (the surface facing the substrate Sw), and the vaporized or sublimated organic material (hereinafter referred to as "organic molecules 61") is emitted from each emission opening 54 according to a predetermined cosine law.

When a predetermined organic film is deposited on the underside of the substrate Sw by the vacuum deposition device Dm, the crucible 52 is filled with solid organic material 6 from its bottom surface to a predetermined height position in the atmospheric atmosphere in the vacuum chamber 1, and then the crucible 52 is evacuated to a predetermined pressure by a vacuum pump not shown. Next, when the heating means 53 is operated to heat the organic material 6, the organic material 6 is vaporized or sublimated to form a vaporization atmosphere or sublimation atmosphere in the storage box 51, and organic molecules 61 are released from each release opening 54 according to a predetermined cosine law due to the pressure difference with the inside of the vacuum chamber 1. At the same time, the substrate Sw is transported in the X-axis direction by the substrate transport device 2. As a result, the organic molecules 61 released from each release opening 54 according to the predetermined cosine law adhere to and accumulate on the underside of the substrate Sw that moves relative to the storage box 51 in the X-axis direction, and the predetermined organic film is deposited.

When the organic film is formed as described above, the vaporized or sublimated organic molecules 61 also adhere and accumulate on the surface of the adhesion prevention plate MP, which receives the direct adhesion (incidence) of the organic molecules 61 from the emission opening 54 according to a predetermined cosine law, forming an organic film 62. Here, as shown in FIG. 2(a), if the molecular orientation direction of the organic molecules 61 adhered to the surface of the base material (metal) Bm, such as stainless steel or aluminum, constituting the adhesion prevention plate MP, is perpendicular (normal direction) to the adhesion prevention plate MP surface, the organic film 62 grows so as to extend convexly in the normal direction. If the grown organic film 62 blocks the scattering path of the organic molecules 61 scattered from the emission opening 54 of the storage box 51, this leads to a decrease in the film formation rate and film thickness distribution.

In this embodiment, a molecular orientation control film Cm is formed on the surface of the adhesion prevention plate MP as the base material (metal) Bm that receives the direct adhesion (incidence) of the organic molecules 61 according to a predetermined cosine law at least as viewed from the emission opening 54. As the molecular orientation control film Cm, for example, a material selected from Ag, Au, graphite, and graphene is used. In this case, the molecular orientation control film Cm can be formed by a physical film formation method such as a plating method, a vacuum deposition method, or a sputtering method, or a coating method using ink, and the film thickness of the molecular orientation control film Cm is not particularly limited as long as it is a so-called continuous film.

As a result, when a molecular orientation control film Cm such as Ag, Au, graphite, or graphene is present, the molecular orientation direction of the organic molecules 61 becomes tangential as shown in FIG. 2(b) or FIG. 2(b) due to the interaction between the d-electron cloud or π-electron cloud spreading on the surface of the molecular orientation control film Cm and the π-electron cloud of the organic molecules 61 attached to the surface, and as a result, the organic film 62 formed on the surface of the molecular orientation control film Cm tends to grow in the tangential direction, and the growth of the organic film 62 in the normal direction is suppressed. As a result, compared to a case where the molecular orientation control film Cm is not formed on the surface of the adhesion prevention plate MP on which the organic film 62 is formed (i.e., a case where the molecular orientation direction of the organic molecules 61 shown in FIG. 2(a) is the normal direction), the growth of the organic film 62 formed on the surface of the adhesion prevention plate MP is suppressed in a convex shape, and the vacuum deposition device Dm can be continuously operated for more than twice as long. In addition, the organic film 62 formed on the surface of the molecular orientation control film Cm has a higher density than one without the molecular orientation control film Cm, which further reduces particle generation from the organic film 62 on the surface of the adhesion prevention plate MP, allowing for even longer continuous operation.

Next, the following evaluation was performed using the vacuum deposition apparatus Dm. That is, an amine derivative was used as the organic material 6, and after evacuating the inside of the vacuum chamber 1 to a predetermined pressure (10 ^-5 Pa), the heating means 53 was operated to sublimate the organic material 6, and a film was continuously formed for 50 hours. At this time, two silicon wafers (sample 1, sample 2) were attached to the surface of the adhesion prevention plate MP located near the emission opening 54 and receiving direct adhesion (incidence) of the organic molecules 61 according to a predetermined cosine law as viewed from the emission opening 54. Then, for one of the samples, sample 2, a gold film was previously formed as a molecular orientation control film Cm with a thickness of 10 nm on the silicon wafer surface by vacuum deposition.

Figure 3 shows the results of evaluating the organic film 62 formed on samples 1 and 2 by X-ray diffraction analysis (XRD). According to this, a peak corresponding to the molecular orientation control film Cm and a peak corresponding to the organic film 62 in which the molecular orientation direction of the organic molecules 61 is the tangential direction were observed, and it was confirmed that the molecular orientation direction of the organic molecules 61 is the tangential direction shown in Figure 2 (C). In addition, when the thickness of the organic film 62 formed on samples 1 and 2 was measured, it was confirmed that the thickness of sample 2 was about half that of sample 1, and that the film density of sample 2 was about twice that of sample 1.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above. In the above embodiment, the vacuum deposition apparatus Dm has been described as an example of the vacuum deposition apparatus, but the present invention is not limited to this, and the present invention can also be applied to parts that exist in the chamber and on which organic molecules are deposited when an organic film is deposited on a substrate Sw by a method of depositing an organic film, such as a sputtering method, a plasma polymerization method, or a deposition polymerization method. In the above embodiment, the deposition prevention plate MP has been described as an example of a part for the vacuum deposition apparatus Dm, but the present invention can also be applied to mask plates, regulating plates, and other parts that exist in the vacuum chamber 1 and on which organic molecules 61 are deposited.

Dm...vacuum deposition device, Sw...substrate (object to be film-formed), MP...adhesion prevention plate (part), Bm...base metal, Cm...molecular orientation control film, 1...vacuum chamber, 6...organic material, 61...organic molecule, 62...organic film.

Claims (2)

A part for a vacuum film-forming apparatus that is disposed around a vapor deposition source in a vacuum chamber so that the organic molecules emitted from the vapor deposition source directly adhere to and deposit on a surface of an object to form an organic film when vaporizing or sublimating an organic material from a vapor deposition source in a vacuum chamber in a vacuum atmosphere and attaching or depositing the vaporized or sublimated organic molecules on the surface of an object to form an organic film, the part comprising:
A component for a vacuum film-forming apparatus, comprising a base material and a molecular orientation control film made of Ag or Au formed to a predetermined thickness on the surface of the base material to which organic molecules adhere, and configured so that an organic film is grown in a tangential direction by aligning the molecular orientation of the organic molecules in the tangential direction through interaction between the d-electron cloud or π-electron cloud spreading on the surface of the molecular orientation control film and the π-electron cloud of the organic molecules adhered to the molecular orientation control film. The vacuum deposition device component according to claim 1, characterized in that the molecular orientation control film is selected from the group consisting of Ag, Au, graphite, and graphene.

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