JP2008111161A - Vapor deposition apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vapor deposition apparatus in which while radiant heat from a crucible is shielded, the falling of deposited material causing a variation in a vapor deposition rate and the generation of splashes can be prevented. <P>SOLUTION: The vapor deposition apparatus is provided with: a vacuum vessel 1 having an exhaust device 2; the crucible 8 storing a vapor deposition material 7; a heating apparatus melting and evaporating the evaporation material 7; and a substrate 4 on which the evaporated material is deposited. A plurality of shielding plate 13 each having an opening part are spaced at intervals each other above the crucible 8, and the opening area of the opening part in each shielding plate 13 is expanded as the shielding plate is close to the substrate 4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an evaporation apparatus for evaporating an evaporation material on a substrate, and more particularly to the configuration of an evaporation source included in the evaporation apparatus.

  In recent years, thin film production using a vapor deposition apparatus has been widely used as a large area / high speed thin film production method. From the viewpoint of reducing the manufacturing cost, it is important to change the deposited film produced by the thin film production using this deposition apparatus to a more stable and high quality deposited film.

  Hereinafter, a conventional vapor deposition apparatus will be described with reference to the drawings. FIG. 6 is a configuration diagram illustrating an example of a conventional vapor deposition apparatus. 7-9 is sectional drawing which shows typically an example of the evaporation source with which the conventional vapor deposition apparatus is equipped.

  As shown in FIG. 6, the conventional vapor deposition apparatus includes an unwinding roll 3 around which a thin film substrate 4 is wound, traveling rollers 5 a and 5 b, a substrate cooling roll 6, and an evaporation material 7 inside a vacuum vessel 1. A crucible 8, an electron beam irradiation device 9 for irradiating the crucible 8, a take-up roll 11, and a mask 10 disposed between the substrate cooling roll 6 and the crucible 8 are provided. Further, an exhaust device 2 is provided outside the vacuum vessel 1.

  The inside of the vacuum vessel 1 is kept at a predetermined degree of vacuum by being evacuated by the exhaust device 2. In the vacuum container 1, the substrate 4 from the unwinding roll 3 travels in the direction of the arrow in FIG. 6 in the order of the traveling roller 5 a and the substrate cooling roll 6. When the substrate 4 passes through the substrate cooling roll 6, the evaporation material 7 is dissolved and evaporated from the crucible 8 irradiated with the electron beam by the electron beam irradiation device 9, so that the evaporation material 7 is given to the substrate 4 in a predetermined manner. Vapor deposition within an angular range. Thereafter, the vapor-deposited substrate 4 is guided to the traveling roller 5 b and finally taken up by the take-up roll 11.

  However, in the above vapor deposition apparatus, there may be a problem that radiant heat from the crucible 8 serving as an evaporation source adversely affects the substrate 4 during vapor deposition of the high melting point material. For example, when an electrode for a lithium ion secondary battery is formed, a copper foil is obtained by dissolving and evaporating silicon (melting point: 1410 ° C.) of an evaporation material placed in a carbon crucible (sublimation point 3367 ° C.) with an electron beam. Silicon is vapor-deposited on a substrate (melting point: 1085 ° C.). At this time, the molten silicon melt and the surface of the carbon crucible 8 are at a high temperature of about 2000 ° C. For this reason, although depending on the distance between the evaporation source and the copper foil substrate, the radiant heat heats the copper foil substrate, so that the formed electrode is wrinkled, the formed film is peeled off, or the copper foil substrate is broken. May occur.

  In order to reduce the occurrence of the above problems, as shown in FIGS. 7 to 9, an evaporation apparatus in which a shielding plate 13 is arranged on the surface of the crucible 8 has been proposed sequentially.

  In the configuration of FIG. 7, radiation heat from the surface of the crucible 8 can be shielded by installing the cooling plate 12 on the shielding plate 13 and the shielding plate 13. However, since the shielding plate 13 is thin, the surface of the shielding plate 13 is reached. The temperature becomes high and the radiant heat from the surface of the shielding plate 13 cannot be ignored.

In the configuration of FIG. 8, the shielding effect is enhanced by increasing the thickness of the shielding plate 13 and installing the cooling pipe 12 inside the shielding plate 13. For this reason, the temperature rise on the surface of the shielding plate 13 is suppressed, and the radiation heat from the surface of the shielding plate 13 is sufficiently shielded. However, as deposition progresses,
The evaporated particles in contact with the shielding plate 13 adhere to the shielding plate 13 as the deposit 14 as shown in FIG. The adhering matter 14 accumulates on the shielding plate 13 over time, and closes the space above the molten metal surface of the evaporating material 7. For this reason, the electron beam irradiation area | region to the evaporation material 7 reduces, evaporation amount reduces, and the arrival amount of the evaporation particle to the board | substrate also reduces. Further, the deposit 14 is melted again and falls into the crucible 8, whereby the deposition rate fluctuates and splash occurs.

In the configuration of FIG. 9, the shielding plate 13 has a cylindrical shape protruding upward, and in particular, the thickness of the upper end of the cylindrical shape is reduced to make the side surface of the shielding plate 13 have a steep angle. Adhesion is reduced (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 2001-3158

  However, the improved configuration of FIG. 9 still has the problem of fluctuations in the deposition rate and the occurrence of splash due to the fall of the deposit 14.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a vapor deposition apparatus that prevents falling of deposits that cause fluctuations in vapor deposition rate and occurrence of splash while shielding radiant heat from a crucible. To do.

  In order to solve the above-mentioned problems, a vapor deposition apparatus according to the present invention comprises a vacuum vessel provided with an exhaust device, a means for installing a crucible for storing an evaporation material, a heating device for melting and evaporating the evaporation material, and an evaporated substance. A plurality of shielding plates having openings at the top of the crucible, spaced apart from each other, and each opening of the plurality of shielding plates. The closer the opening area of the part is to the substrate, the larger.

  With this configuration, it is possible to prevent the deposits from falling while shielding the radiant heat from the crucible.

  According to the vapor deposition apparatus of the present invention, a plurality of shielding plates having openings at the upper part of the crucible are arranged with a space between each other, and the opening area of the openings of the shielding plates increases as the substrate approaches the substrate. Therefore, even if the deposit formed on the side wall of the shielding plate falls, it is received on the upper surface of the shielding plate located in the lower part, and the fluctuation of the deposition rate due to the deposit falling in the crucible, Occurrence can be prevented.

  Moreover, according to the vapor deposition apparatus of the present invention, since it is configured to use a plurality of shielding plates, the shielding plate located in the upper part absorbs radiant heat from the surface of the shielding plate located in the lower part. Radiant heat from the surface of the shielding plate located can be reduced more than radiation heat from the surface of the shielding plate located in the lower part, and further radiation heat reaching the substrate surface can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the embodiment of the present invention, an example applied to an electron beam vapor deposition apparatus is described. However, the present invention is not limited to this, and the present invention is not limited to this. In addition, the present invention can be applied to any vapor deposition apparatus including a heating apparatus that melts and evaporates the evaporation material and a substrate to which the evaporated substance is attached. Further, in the embodiment of the present invention, the basic configuration of the vapor deposition apparatus other than the structure of the evaporation source is the same as that of the conventional vapor deposition apparatus shown in FIG.

(Embodiment 1)
FIG. 10 is a schematic cross-sectional view of the vapor deposition apparatus according to Embodiment 1 of the present invention, and FIG. 1 is an enlarged cross-sectional view of the vicinity of the evaporation source of the vapor deposition apparatus of FIG. FIG. 2 is a perspective view of a shielding plate provided in the vapor deposition apparatus according to Embodiment 1 of the present invention. 10, 1, and 2, the same reference numerals are used for the same components as those in FIG. 7.

  As shown in FIG. 10 and FIG. 1, the vapor deposition apparatus of the present embodiment melts and evaporates the evaporation material 7, the vacuum vessel 1 provided with the exhaust device 2, the means for installing the crucible 8 that stores the evaporation material 7, and A heating device 9 and means for installing the substrate 4 to which the evaporated substance is attached are provided. The substrate 4 unwound from the unwinding roll 3 is wound around the winding roll 11 via the traveling roller 5a, the substrate cooling roll 6, and the traveling roller 5b. During this time, while the substrate 4 is cooled on the substrate cooling roll 6, evaporated atoms evaporated from the evaporation material 7 are deposited.

  A crucible 8 shown in FIG. 1 is made of, for example, carbon, and contains an evaporating material 7 and is heated and melted by an electron beam irradiation device 9. As shown in FIG. 2, a three-stage shielding plate 13 having an opening having the same shape as the opening edge of the crucible 8 is disposed on the upper portion of the crucible 8. The shielding plate 13 is made of, for example, copper, and is configured such that the opening area of the opening portion of the shielding plate 13 increases as it approaches the substrate 4 with a predetermined interval therebetween. Although not shown, the three-stage shielding plate 13 is supported substantially parallel to the surface of the crucible 8 by a normal support mechanism.

  According to the configuration of the vapor deposition apparatus in Embodiment 1 of the present invention, when the evaporating material 7 is heated and melted by being irradiated with an electron beam and evaporated, even if the deposit 14 deposited on the shielding plate 13 falls, By being received by the upper surface of the shielding plate 13 located in the lower part, it is possible to prevent the deposition rate from fluctuating due to the deposit 14 falling into the crucible 8 and the occurrence of splash.

  Moreover, in the vapor deposition apparatus in Embodiment 1 of this invention, by using the some shielding board 13, the shielding board 13 located in the upper part absorbs the radiant heat from the surface of the shielding board 13 located in the lower part. The radiant heat from the surface of the shielding plate 13 located in the upper part can be reduced more than the radiant heat from the surface of the shielding plate 13 located in the lower part, and further the radiant heat reaching the surface of the substrate 4 can be reduced. it can.

  The installation standard of the shielding plate 13 in Embodiment 1 of the present invention is as follows.

  The number of the shielding plates 13 to be installed is determined by the surface temperature of the crucible 8 at the time of vapor deposition, the thickness of the shielding plate 13, and the like, but it is sufficient that the number of the shielding plates 13 can sufficiently reduce the radiant heat from the surface of the crucible 8. Even if the shielding plate 13 is installed more than necessary, it only gives a load to the apparatus cost, cleaning work after vapor deposition, and the like.

  The distance between the shielding plates 13 is mainly determined by the vapor deposition rate and the vapor deposition time. However, when the predetermined vapor deposition time is finished, the distance by which the deposits or deposits due to the fall of the deposits do not connect the shield plates 13 to each other. If there is. For example, when evaporating material 7 with a deposition rate of 400 nm per second is vapor-deposited for a total of 8 hours, the thickness of the vapor-deposited film is about 11.5 mm even when the substrate 4 is stationary. A length of 15 mm is sufficient.

The size of the opening of each shielding plate 13 is determined by the size of the opening of the crucible 8 and the opening of the mask 10. As shown in FIG. 10, an inner region connecting the opening edge of the crucible 8 and the opening edge of the mask 10 becomes an incident region A of the evaporated particles to the substrate 4. Each shielding plate 13 needs to have at least an opening in contact with the incident area A at each installation height. If it is smaller than this, the deposition area on the substrate 4 defined by the mask 10 is narrowed. Moreover, if it expands too much, it is because the radiant heat which reaches | attains the board | substrate 4 from the surface of the crucible 8 or the shielding board 13 will increase. Accordingly, the size of the opening of the shielding plate 13 should be limited to 1.25 times the size of the opening contacting the incident area A in terms of area.

(Embodiment 2)
FIG. 3 is a cross-sectional view of the evaporation source provided in the vapor deposition apparatus according to Embodiment 2 of the present invention. Since the evaporation source according to the second embodiment of the present invention shown in FIG. 3 has the same configuration as that of the first embodiment, the same reference numerals are used for the same components as in FIG. 1, and only different parts will be described below. .

  As shown in FIG. 3, the shielding plate 13 is configured such that the cross-sectional shape of the opening end is provided with an inclined portion 15 having a larger opening area at the substrate 4 side end than at the crucible 8 side end. Yes. In FIG. 3, the inclined portion 15 is inclined over the entire surface. However, even if an inclined portion is provided on a part of the plurality of shielding plates 13, there are some effects. In addition, even in the case where a single shielding plate is provided with the inclined portion 15 at a part of the opening end portion, there is a certain effect.

  According to the structure of the vapor deposition apparatus in Embodiment 2 of this invention, besides having the same effect as Embodiment 1, formation of the deposit | attachment 14 to the opening edge part of the shielding board 13 can be delayed, and the said opening It is possible to reduce the evaporated particles that are blocked by the deposit 14 deposited on the end. As a result, it is possible to form a vapor deposition film that is more stable and has a higher quality for a long time.

  In Embodiments 1 and 2 of the present invention, a prismatic crucible is used and carbon is used as a crucible material. However, a desired evaporation material can be accommodated, and dissolution and evaporation by a heating device can be performed stably and safely. As long as it can be used, its shape and material are arbitrary.

  In the first and second embodiments of the present invention, the electron beam irradiation device is used as the heating device. However, if the desired evaporation material can be heated and dissolved, other heating devices such as resistance heating and induction heating can be used. May be used.

  In Embodiments 1 and 2 of the present invention, a copper shielding plate is used. However, other materials may be used as long as a desired radiant heat reduction effect can be exhibited. Furthermore, in order to enhance the effect of reducing radiant heat, a cooling pipe for flowing water, a refrigerant, or the like may be provided inside the shielding plate or on the substrate side surface.

  Further, in Embodiments 1 and 2 of the present invention, the formation of the opening portion of the shielding plate 13 is described in the form of making a hole in the shielding plate 13, but as shown in FIGS. 4 (a) and 4 (b), A plurality of plates may be combined to form the opening. Or as shown to Fig.5 (a), (b), it is good also considering the opening part of the shielding board 13 as a cross-beam structure. Also in the cross-girder structure, as in the first and second embodiments of the present invention, the remelted fallen material from the upper shielding plate 13 is received by the lower shielding plate 13 and remelted into the crucible 8. It is possible to prevent sudden changes in the evaporation state due to falling objects, fluctuations in the deposition rate, and occurrence of splash.

  The vapor deposition apparatus according to the present invention has a plurality of shielding plates having openings at the top of the crucible, and is useful as a vapor deposition apparatus that can prevent falling of deposits while shielding radiant heat from the crucible. .

Sectional drawing of the evaporation source with which the vapor deposition apparatus in Embodiment 1 of this invention is equipped The perspective view of the shielding board with which the vapor deposition apparatus in Embodiment 1 of this invention is equipped. Sectional drawing of the evaporation source with which the vapor deposition apparatus in Embodiment 2 of this invention is equipped (A) The perspective view which shows an example of the opening part structure which concerns on this invention (b) The perspective view which shows an example of the opening part structure which concerns on this invention (A) Sectional drawing which shows an example of opening part structure which concerns on this invention (b) Perspective view of (a) Configuration diagram showing an example of a conventional vapor deposition apparatus Sectional drawing which shows an example of the evaporation source with which the conventional vapor deposition apparatus is equipped Sectional drawing which shows an example of the evaporation source with which the conventional vapor deposition apparatus is equipped Sectional drawing which shows an example of the evaporation source with which the conventional vapor deposition apparatus is equipped Sectional drawing of the vapor deposition apparatus in Embodiment 1 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum container 2 Exhaust device 3 Unwinding roll 4 Substrate 5a, 5b Traveling roller 6 Substrate cooling roll 7 Evaporating material 8 Crucible 9 Electron beam irradiation apparatus 10 Mask 11 Winding roll 12 Cooling tube 13 Shielding plate 14 Adhering matter 15 Inclined part

Claims (2)

A vapor deposition apparatus comprising a vacuum vessel provided with an exhaust device, a means for installing a crucible for storing the evaporation material, a heating apparatus for melting and evaporating the evaporation material, and a means for installing a substrate to which the evaporated substance is attached. A plurality of shielding plates having openings at the top of the crucible are spaced apart from each other, and the vapor deposition apparatus becomes larger as the opening area of each opening of the plurality of shielding plates is closer to the substrate. The vapor deposition apparatus of Claim 1 with which the opening part of the said shielding board has a crucible side edge part and a substrate side edge part, and the opening area of the said substrate side edge part is wider than the opening area of a crucible side edge part.

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