JP2015101757A - Film deposition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film deposition method capable of forming a film having high reliability by high quality by suppressing a heat influence from a heat source upon evaporation or upon sputtering even to a film deposition object member having a three-dimensional structure in film deposition processing.SOLUTION: When applying film deposition processing to a film deposition object member 1 comprising a resin material by an evaporation method or a sputtering method under a vacuum environment, a first mask 10 is arranged adherently to the film deposition object member 1 to which the film deposition processing is applied, and a second mask 20 having excellent heat reflectivity is arranged at a prescribed fixed interval from the first mask 10 so as to cover the first mask 10.

Description

  The present invention relates to a film forming method, and more particularly to a film forming method for performing a film forming process on the surface of a resin member.

  Conventionally, as this type of film forming method, for example, Patent Document 1 discloses a method as shown in FIG. 6 as a “thin film forming method”.

  In the chamber 70 in a low-vacuum atmosphere, a heat-deposited mask 72 having a plurality of through-holes 71 is disposed on a thin film forming surface 73 in close contact with a deposition substrate 74 and a ceramic heater 75 via a stage 76. At the same time, a vapor deposition source 79 having a thin film material (VDF oligomer) 78 disposed on the upper surface of the plate 77 is opposed to each other, and is brought close to each other to bring the heat insulating mask 72 and the vapor deposition source 79 into surface contact.

  Then, by heating the ceramic heater 75 in a state where the heat insulating mask 72 and the vapor deposition source 79 are kept in surface contact, gas molecules of the sublimated thin film material are passed through the through holes 71 of the heat insulating mask 72 and both ends of the through holes 71. In the closed space formed by the thin film formation surface 73 of the deposition target substrate 74 and the thin film material supply surface 80 of the deposition source 79 arranged so as to close the opening, the film is supersaturated and deposited on the thin film formation surface 73 of the deposition target substrate 74. A thin film is formed by deposition.

  Patent Document 2 discloses a method of using a mask jig as shown in FIG. 7 as a “mask jig”.

  That is, a mirror surface forming mask jig 91 simulating a three-dimensional lamp unit 90 having a curved surface is manufactured, and the lamp jig 90 is attached to the lamp unit 90 with the mask jig 91 attached thereto. A reflective metal is vacuum-deposited on a desired mirror surface formation region 93 of the unit 90 to obtain a lamp unit 90 having a mirror surface 94.

Japanese Patent No. 4881774 Japanese Patent No. 4096334

  By the way, in the thin film forming method of Patent Document 1, a heat insulating material such as quartz or ceramic is used for the heat insulating mask. Therefore, there exists a problem that formation of the heat insulation mask arrange | positioned closely is difficult with respect to the vehicle lamp of the three-dimensional structure which has a curved surface.

  The mask jig of Patent Document 2 uses a resin material such as PVC, acrylic, polypropylene, epoxy, polycarbonate, ABS, or a metal material such as zinc, aluminum, copper, or iron as a material.

When a resin material is used for the mask jig, gas (mainly H ₂ O vapor) is released from the heated mask jig by directly receiving heat from a heat source during vapor deposition or sputtering, and the released gas is When the metal reflection film is formed, the metal reflection film may be mixed, thereby oxidizing the metal reflection film and reducing the light reflectance.

On the other hand, when a metal material is used for the mask jig, the heat of the mask jig heated by receiving heat during vapor deposition or sputtering heats the resin part of the lamp unit that is in direct contact with the mask jig. Gas (mainly H ₂ O vapor) is released from the heated portion, and the released gas is mixed into the metal reflection film during the formation of the metal reflection film, and the metal reflection film is thereby oxidized. As a result, the light reflectance may decrease.

  As a three-dimensional mask jig using a metal material, for example, a method using an electroplated layer obtained by electroforming can be considered. In this case, when the mask jig becomes large, the whole is assembled by soldering by dividing into a plurality of parts in consideration of the processing capacity or productivity with respect to the size of the manufacturing equipment.

  In that case, gas is generated from solder having a low melting point by directly receiving heat during vapor deposition or sputtering, and the generated gas is mixed into the metal reflective film during the formation of the metal reflective film. Oxidation, yellowing, dullness, etc. may occur and the light reflectance may decrease.

  Therefore, the present invention was devised in view of the above problems, and the object of the present invention is to apply heat during vapor deposition or sputtering even to a three-dimensional film-forming member having a curved surface during film formation. It is an object of the present invention to provide a film forming method capable of forming a highly reliable film with high quality by suppressing the influence of the above.

  In order to solve the above-mentioned problem, the invention described in claim 1 of the present invention is a film forming method in a vacuum environment, wherein the film forming member to be subjected to film forming processing is provided with an opening. A second mask having an opening and having a heat reflective property at a predetermined constant distance from the first mask so as to cover the first mask; The film forming process is performed on the film forming member through the respective openings of the double mask of the first mask and the second mask.

  The invention described in claim 2 of the present invention is characterized in that, in claim 1, the distance d is 0 <d ≦ 2 mm.

  According to a third aspect of the present invention, in the first or second aspect, the first mask is made of a metal material.

  Further, in the invention described in claim 4 of the present invention, in any one of claims 1 to 3, the surface on which the film forming process of the film forming member is performed is a surface including a three-dimensional surface. It is characterized by this.

  According to the film forming method of the present invention, a first mask having an opening is disposed in close contact with a film forming member on which a film forming process is performed, and the first mask and a predetermined mask are covered so as to cover the first mask. A second mask having an opening having heat reflectivity at a constant interval is disposed, and the deposition is performed through each opening of the double mask by the first mask and the second mask. A film forming process was performed on the film member. In addition, the second mask is specifically fixed to the first mask by being placed on a fixing jig or the like in a chamber that is thermally separated so as not to contact the first mask and the deposition target member. The interval is secured.

  Thereby, the heat from the heat source during film formation is located between the second mask 20 (heat shielding mask) located on the outermost side with respect to the film formation target member and the first mask and the second mask. The first mask placed in close contact with the film forming member is protected from heating and the temperature rise is suppressed, and at the same time, the first mask is placed in close contact. Further, the temperature rise on the film forming surface of the film forming member is also suppressed.

  As a result, it is possible to prevent a film defect during film formation due to a temperature increase of the first mask placed in close contact with the film forming member, and to form a highly reliable film with high quality.

It is process explanatory drawing of the film-forming method. Similarly, it is process explanatory drawing of the film-forming method. Similarly, it is process explanatory drawing of the film-forming method. Similarly, it is process explanatory drawing of the film-forming method. Similarly, it is process explanatory drawing of the film-forming method. It is explanatory drawing of a prior art example. Similarly, it is explanatory drawing of a prior art example.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIG. 1 to FIG. 5 (the same reference numerals are given to the same portions). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  1-5 is the figure which showed typically the process of the film-forming method of this invention.

  The film forming direction of the present invention is achieved through a mask disposed in a double manner with respect to a film forming processing member (hereinafter referred to as “film forming member”) in a vacuum environment having a predetermined degree of vacuum. A film treatment is performed.

  First, a film forming member 1 as shown in FIG. 1 is prepared. The film-forming member 1 is made of a resin material such as polycarbonate, ABS, PVC, polypropylene, or acrylic, and a surface (film-forming surface) 2 on which a film-forming process is performed includes a surface including a three-dimensional surface.

  Next, in the film forming process, as shown in FIG. 2, the first mask 10 is disposed in close contact with the film forming surface 2 of the film forming member 1. The first mask 10 is a metal mask, and, for example, a mask that is integrally assembled by joining metal plating layers obtained by dividing into a plurality of parts by electroforming using solder. The first mask 10 has an opening 11 penetrating in the thickness direction in a region corresponding to a desired film formation region 3 on the film formation surface 2 when closely arranged on the film formation surface 2 of the film formation target member 1. Is provided.

  Next, as shown in FIG. 3, a predetermined constant distance d is provided so as to cover the first mask 10 above the first mask 10 disposed in close contact with the film formation surface 2 of the film formation target member 1. A second mask 20 is disposed along the upper surface 12 of the first mask 10. Similar to the first mask 10 described above, the second mask 20 is, for example, integrally assembled by joining metal plating layers obtained by dividing into a plurality of parts by electroforming using solder. Used. The second mask 20 is provided with an opening 21 penetrating in the thickness direction in the opening region 13 corresponding to the opening 11 in the first mask 10 when the second mask 20 is disposed above the first mask 10.

  Next, as shown in FIG. 4, the first mask 10 is disposed in close contact with the film formation surface 2 of the film formation target member 1, and the first mask 10 is placed at a predetermined constant interval d. In a state where the second mask 20 is disposed and held along the upper surface of the first mask 10, it is released by sputtering of a target in vapor deposition molecules evaporated by heating of a vapor deposition source or vacuum sputtering in a vacuum vapor deposition method. The emitted atoms fly toward the second mask 20 located on the outermost side with respect to the deposition target member 1, and are covered under the opening 21 provided in the second mask 20 and the second mask 20. The first mask 10 disposed in close contact with the film forming member 1 is sequentially passed through the opening 11 of the film forming member 1 and adheres to a desired region of the film forming surface 2 of the film forming member 1 to form a film 40 (FIG. 5 ( (See film formation diagram).

  In this case, for example, aluminum is used as the film forming material, and the film is formed as an aluminum reflecting film.

  At this time, the radiant heat from the heating source for heating and evaporating the vapor deposition source in the vacuum vapor deposition method or the radiant heat from the plasma for sputtering the target in the vacuum sputtering method is directly emitted to the second mask 20. At this time, the second mask 20 is formed of a material that reflects heat, such as the metal material described above, and most of the radiant heat radiated from the heat source toward the second mask 20 is Reflected by the second mask 20, the radiation downward (first mask 10 side) is shielded. Therefore, the second mask 20 has a function as a heat shield that suppresses the first mask 10 from being heated by the radiant heat from the heat source and rising in temperature.

  Further, the heat received in the second mask 20 by absorbing the radiant heat without being reflected is the heat transfer medium (air) when the gap 30 provided between the first mask 10 and the gap d is in a vacuum state. Therefore, it hardly transmits to the first mask 10 and the temperature rise of the first mask 10 is suppressed.

  By the way, the distance (distance) d of the gap 30 provided between the first mask 10 and the second mask 20 is set based on the Debye length of the plasma, particularly in the film formation by the vacuum sputtering method. The

Specifically, in a vacuum sputtering method, when a low-impedance medium called plasma enters between the first mask 10 and the second mask 20 (between the masks), a short-circuit current flows through the mask and is heated. In order to prevent this heating, it is necessary to prevent plasma from entering between the masks. The outermost surface of the wall placed in the plasma is covered with an ion sheath, and the plasma exists in a region away from the ion sheath. Therefore, if the gap between the masks is made smaller than the thickness of the ion sheath, plasma does not enter between the masks. Further, according to the inventor's knowledge, the thickness of the ion sheath is several times to several tens of times the Debye length, and a substantial mask interval d can be set based on the thickness of the ion sheath and the Debye length λ _D. is there.

The calculation of the mask interval d is shown below.
λ _D (cm) = 6.9 {Te (K) / Ne (cm ⁻³ )} ^1/2
Te: electron temperature, Ne: electron density Electron temperature and electron density are Te = 100000 (K) and Ne = 10 ⁹ (cm ⁻³ ), respectively.
λ _D = 6.9 ⁻² cm.
The ion sheath is about several times to several tens of times of 0.69 mm, and since the width of the ion sheath is large, the ion sheath of about 3 times is 2.07 mm in view of safety. Therefore, if the mask interval d is 2 mm or less, plasma does not enter. Further, in order to prevent the heat of the second mask 20 from being conducted to the first mask 10, the mask interval d needs to be d> 0.

  As a result, by setting the interval (distance) d of the gap 30 provided between the first mask 10 and the second mask 20 in a range of 0 <d ≦ 2, the plasma wraps around the gap 30. It is possible to prevent the first mask 10 from directly receiving the radiant heat from the heat source and to prevent the temperature of the first mask 10 from rising.

  As described above, in the film forming method of the present invention, when the film forming process is performed by the vapor deposition method or the sputtering method in a vacuum environment, the first mask 10 is applied to the film forming member 1 on which the film forming process is performed. The second mask 20 made of, for example, a metal material having good heat reflectivity is disposed at a predetermined fixed distance from the first mask 10.

  Thus, by arranging the masks in duplicate, the heat from the heat source at the time of vapor deposition or sputtering, the second mask 20 (heat shielding mask) positioned on the outermost side with respect to the film formation member 1 and The first mask 10 disposed in close contact with the deposition target member 1 is protected from heating by being blocked by a gap (vacuum heat insulating layer) located between the first mask 10 and the second mask 20. At the same time, the temperature rise is suppressed, and at the same time, the temperature rise of the film formation surface of the film formation target member 1 on which the first mask 10 is closely arranged is also suppressed.

  As a result, when a film formation process is performed on a film forming member formed of a surface including a three-dimensional surface, for example, a mask arranged in close contact with the film formation surface including the three-dimensional surface is provided. Therefore, it is possible to form a highly reliable film with high quality.

  In other words, even if the metal member obtained by dividing into a plurality of parts is joined by soldering, even if the mask assembled integrally is placed in close contact with the film forming member, gas is generated from the low melting point solder. In addition, there is no problem that the light reflection rate is lowered due to oxidation, yellowing, dullness, etc. of the formed metal reflective film.

Further, there is no emission of gas (mainly H ₂ O vapor) from the portion where the first mask of the film formation member made of a resin material is closely attached, and the metal reflective film is oxidized to reduce the light reflectance. Such a problem does not occur.

DESCRIPTION OF SYMBOLS 1 ... Film-forming processing member 2 ... Film-forming surface 3 ... Film-forming area | region 10 ... 1st mask 11 ... Opening 12 ... Upper surface 13 ... Opening area 20 ... 2nd mask 21 ... Opening 30 ... Gap 40 ... Film-forming

Claims (4)

A film forming method in a vacuum environment,
A first mask having an opening is disposed in close contact with a deposition target member to be deposited;
A second mask having an opening and having heat reflectivity is disposed at a predetermined constant distance from the first mask so as to cover the first mask;
A film forming method, wherein the film forming member is subjected to a film forming process through respective openings of a double mask composed of the first mask and the second mask.   The film formation method according to claim 1, wherein the interval d satisfies 0 <d ≦ 2 mm.   The film forming method according to claim 1, wherein the first mask is made of a metal material.   The film forming method according to claim 1, wherein a surface of the film forming member to be subjected to film forming processing is a surface including a three-dimensional surface.

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