JP2010265508A - Thin film manufacturing apparatus and manufacturing method - Google Patents

Abstract

A thin film manufacturing apparatus and a thin film manufacturing method for reducing a vapor deposition cost by reducing a vapor deposition container replacement frequency by securing a passage for performing a volume change in thermal expansion of a vapor deposition material and preventing a vapor deposition container from being broken or damaged. To provide.
A thin film manufacturing apparatus according to the present invention is a thin film manufacturing apparatus 100 that forms a film on a surface of a substrate 4 using vacuum vapor deposition, and includes a vapor deposition raw material, a container 16 for containing the vapor deposition raw material, Heating means 17 for heating the vapor deposition raw material 16 accommodated in the container, and when the heating means 17 heats and melts the vapor deposition raw material, the lower side of the vapor deposition raw material communicates with the upper side of the melting surface. A thin film manufacturing apparatus having a pipe 50 to be operated.
[Selection] Figure 1

Description

  The present invention relates to a thin film manufacturing apparatus and a thin film manufacturing method, and more particularly to a thin film manufacturing apparatus and a thin film manufacturing method used as an electrode for a nonaqueous electrolyte secondary battery.

  2. Description of the Related Art In recent years, as mobile devices have higher performance and more functions, there is a strong demand for higher capacity secondary batteries as power sources. In order to increase the capacity of secondary batteries, lithium secondary battery electrodes using a negative electrode active material such as silicon (Si), germanium (Ge), or tin (Sn) are being actively studied.

  In a lithium secondary battery electrode using silicon, the electrode active material expands and contracts violently due to repeated charge and discharge, and pulverization and miniaturization occur. This increases the surface area and promotes the decomposition reaction of the electrolyte. The problem is that the current collecting property is lowered. Therefore, an electrode in which an electrode active material layer is formed on a current collector using a deposition method such as an evaporation method, a sputtering method, or a CVD method has been studied. Compared to a coated electrode coated with a slurry containing an electrode active material and a binder, an electrode formed by vapor deposition can increase the strength of the film, so that miniaturization of the electrode active material during charging and discharging can be suppressed. it can. In addition, since the current collector and the electrode active material layer can be integrated, the electron conductivity in the electrode can be improved. As a result, an electrode formed by using a deposition method by vapor deposition can be expected to have higher performance in terms of capacity and cycle life than a conventional coating electrode.

  A method of increasing the capacity of an electrode by taking advantage of the characteristics of a film forming method by vapor deposition that can reduce or eliminate a conductive material, a binder, and the like has been studied (for example, see Patent Document 1).

  The electrode created by the deposition method can improve the strength of the electrode active material layer, but the current collector is easily separated from the electrode active material layer due to expansion and contraction of the electrode active material due to charge and discharge. There are problems such as wrinkling on the body. Therefore, a vapor deposition apparatus for obliquely depositing an electrode active material on a substrate having a concavo-convex pattern shape by obliquely forming an angle formed by the normal line standing on the substrate and the normal line standing on the melting surface of the evaporation source of the evaporation source. It has been devised (for example, see Patent Document 2).

  By the way, when a thin film is formed by vacuum evaporation used as an evaporation material, crucible cracking or chipping occurs, crucible replacement frequency increases, continuous operation becomes difficult, and film formation costs increase. It was. Therefore, it has been disclosed to use ceramics whose thermal conductivity and thermal expansion coefficient are smaller than those of the MgO crucible material. (For example, see Patent Document 3)

Japanese Patent Laid-Open No. 11-135115 International Publication No. 2007/15419 Japanese Patent Laid-Open No. 11-172417

When cooling the deposition material after completion of the deposition, there is a problem of destroying the deposition material container due to the difference between the thermal expansion coefficient when cooling the deposition material and the thermal expansion coefficient when cooling the deposition container. If it is sometimes cracked or broken, the frequency of vapor deposition container replacement increases, continuous operation becomes difficult, and the vapor deposition cost increases.

  The present invention relates to a thin film manufacturing apparatus and thin film method for reducing a vapor deposition container replacement frequency and reducing a vapor deposition cost by securing a passage for performing volume change in thermal expansion of a vapor deposition material and preventing vapor deposition container cracking and breakage. The purpose is to provide.

  In order to solve the above-described problems, a thin film manufacturing apparatus of the present invention is a thin film manufacturing apparatus that forms a film on a surface of a substrate using vacuum vapor deposition, and includes a vapor deposition raw material, a container containing the vapor deposition raw material, A heating means for heating the vapor deposition raw material housed in the vessel, and a pipe that communicates the lower side of the vapor deposition raw material and the upper side of the melting surface when the heating means heats and melts the vapor deposition raw material And a thin film manufacturing apparatus.

  The thin film production method of the present invention is a thin film production method for forming a film on the surface of a substrate using vacuum vapor deposition, wherein the vapor deposition material is heated and dissolved (A), A thin film having a step (B) of inserting a tube communicating below the melting surface and above the melting surface into a vessel for dissolving the vapor deposition material, and a step (C) for cooling the vapor deposition material It is a manufacturing method.

  According to the thin film manufacturing apparatus and the thin film manufacturing method of the present invention, the passage for performing volume change in the thermal expansion of the vapor deposition material is secured, and the vapor deposition container replacement frequency is reduced by preventing vapor deposition container cracking and breakage. Cost can be reduced.

FIG. 3 is a schematic cross-sectional view of the thin film manufacturing apparatus according to the first embodiment. (a) is typical sectional drawing of the evaporation source of Embodiment 1. FIG. (b) is typical sectional drawing at the time of material melt | dissolution of the evaporation source 9 of Embodiment 1. FIG. (a) is a schematic top view of the evaporation source 9 of Embodiment 1. FIG. FIG. 4B is another schematic top view of the evaporation source 9 according to the first embodiment. (a) is typical sectional drawing just before the electron beam 30 heating stop of the evaporation source 9 of Embodiment 1. FIG. (b) is typical sectional drawing in the state which cooled after the electron beam 30 heating stop of the evaporation source 9 of Embodiment 1. FIG. (c) is a schematic top view in the state which irradiated the electron beam 30 to the pipe | tube 50 of Embodiment 1. FIG. FIG. 4 is a schematic cross-sectional view of a thin film manufacturing apparatus according to a second embodiment. (a) is typical sectional drawing of the evaporation source of Embodiment 2. FIG. FIG. 4B is a schematic top view of the evaporation source according to the second embodiment. FIG. 6 is a schematic cross-sectional view when the electron beam is stopped in the thin film manufacturing method according to the second embodiment. FIG. 6 is a schematic cross-sectional view at the start of vapor deposition in the thin film manufacturing method according to the second embodiment.

  Hereinafter, embodiments of a method for producing a thin film according to the present invention will be described with reference to the drawings.

(Embodiment 1)
In the thin film manufacturing apparatus of the present embodiment, an example is shown in which a sheet-like substrate is conveyed in a chamber 2 by roll-to-roll and vapor deposition is performed on a cooling can.

<Configuration of thin film manufacturing equipment>
First, refer to FIG. FIG. 1 is a cross-sectional view schematically showing a thin film manufacturing apparatus according to a first embodiment of the present invention.

A thin film manufacturing apparatus 100 is provided outside a chamber (vacuum tank) 2 and an exhaust pump 1 for exhausting the chamber 2, and introduces a gas such as oxygen gas into the chamber 2 from the outside of the chamber 2. Gas inlet pipes 11a and 11b are provided. Further, a driving device for the shutter 12 in the chamber 2, driving devices for the first and second rolls 3 and 8, and a length measurement system 13 are installed. Inside the chamber 2, an evaporation source 9 that evaporates the evaporation source, a transfer unit for transferring the sheet-like substrate 4, a shielding unit that forms a shielding area where the evaporation source evaporated by the evaporation source 9 does not reach, and A shutter part and a nozzle part 22 for supplying gas to the surface of the substrate 4 connected to the gas introduction pipes 11 a and 11 b are provided.

  The evaporation source 9 includes, for example, a container such as a crucible for storing a vapor deposition raw material, and a heating device for evaporating the vapor deposition raw material, and the vapor deposition material and the container 16 are appropriately detachable. As the heating device, for example, a resistance heating device, an induction heating device, an electron beam heating device 17 or the like can be used. In this embodiment, the electron beam heating device 17 is used.

  When vapor deposition is performed, the vapor deposition material accommodated in the crucible is heated by the heating device, evaporates from the upper surface (evaporation source) 9 s, and is supplied to the surface of the substrate 4 by opening and closing the shutter 12. The shutter 12 constituting the shutter unit described above is connected to a driving device installed outside the chamber 2 and can be opened and closed.

  The transport unit includes first and second rolls 3 and 8 that can wind and hold the substrate 4, a guide unit that guides the substrate 4, a drive roller 7 that adjusts the transport direction, and a length measurement system 13. . The length measurement system 13 measures the transport distance and transport speed of the substrate 4 and adjusts the transport length and transport speed. The guide portion has a cooling can 6 and other transport rollers 5a to 5c, so that the substrate 4 passes through a region (evaporation possible region) where the deposition material evaporated from the evaporation surface 9s reaches. A conveyance path of the substrate 4 is defined.

  The first and second rolls 3 and 8 are connected to a driving device installed outside the chamber 2, and can wind and unwind the substrate 4. The driving roller 7 is connected to a driving device installed outside the chamber 2 and can control the transport direction and transport speed of the substrate 4.

  The first and second rolls 3 and 8, the transport rollers 5a to 5c, the drive roller 7 and the cooling can 6 have, for example, a cylindrical shape having a length of 600 mm, and the length direction (that is, transport). The substrate 4 is arranged in the chamber 2 so that the width direction of the substrate 4 is parallel to each other. In FIG. 1, only a cross section parallel to these cylindrical bottom surfaces is shown.

  Note that the evaporation source 9 may also be configured, for example, such that the evaporation surface 9s of the vapor deposition material has a sufficient length (for example, 600 mm or more) parallel to the width direction of the substrate 4 conveyed by the conveyance unit. . Thereby, substantially uniform vapor deposition can be performed in the width direction of the substrate 4. The evaporation source 9 may be composed of a plurality of crucibles arranged along the width direction of the substrate 4 to be transported.

  In the present embodiment, one of the first and second rolls 3 and 8 feeds out the substrate 4, and the drive roller 7, the transport rollers 5 a to 5 c and the cooling can 6 pass the fed substrate 4 along the transport path. The other one of the first and second rolls 3 and 8 takes up the substrate 4.

The wound substrate 4 is further fed out by the other roll as necessary, and is transported in the reverse direction along the transport path. The first roll 3 and the second roll 8 are driven in the direction in which the substrate 4 is wound up, and the substrate is pulled and balanced. Here, by driving the drive roller 7, the substrate 4 moves along the drive roller 7 and can be wound in one direction of the first or second roll 3 or 8. For example, when the drive roller 7 is rotated clockwise in FIG. 1, the substrate 4 is transported in the direction of being wound around the second roll 8. The conveyance speed and the conveyance distance are appropriately adjusted by the length measurement system 13.

  Thus, the 1st and 2nd rolls 3 and 8 in this embodiment can function as a winding roll and a winding roll depending on a conveyance direction. Further, by repeating the reversal of the transport direction, the number of times the substrate 4 passes through the vapor deposition region can be adjusted, so that the desired number of vapor deposition steps can be continuously performed.

  The driving roller 7, the transport roller 5 a, the cooling can 6, and the transport rollers 5 b and 5 c are arranged in this order from the first roll side in the transport path of the substrate 4. In this specification, “the first roll side in the transport path of the substrate 4” means the first and second rolls 3, 8 regardless of the transport direction of the substrate 4 or the spatial arrangement of the first rolls. Means the first roll side on the transport path with both ends. The cooling can 6 is disposed below the adjacent transport rollers 5 a and 5 b, and the vapor deposition region 60 a and the vapor deposition region 60 b are formed in the transport path of the substrate 4.

  A first shielding member 20 is disposed between the cooling can 6 and the evaporation source 9 (evaporation surface 9s), and the vapor deposition material evaporated from the evaporation surface 9s is incident from the normal direction of the substrate 4. While preventing, the vapor deposition area | region on a cooling can is isolate | separated into two. With such a configuration, the first vapor deposition region 60 a located on the first roll side with respect to the cooling can 6 in the transport path of the substrate 4 and the second vapor deposition located on the second roll side with respect to the cooling can 6. Region 60b is formed.

  In the present specification, the name of the vapor deposition region is located on the first roll side of the cooling can 6 regardless of the installation position of the first and second rolls 3 and 8 in the chamber 2 and the transport direction of the substrate 4. If it is located on the second roll side, it becomes the “second vapor deposition region 60b”. Therefore, the “first vapor deposition region 60 a” only needs to be positioned on the first roll side with respect to the cooling can 6 in the transport path of the substrate 4.

  The shielding part is disposed in the deposition possible region, and is disposed so as to cover the exhaust port (not shown) connected to the evaporation source 9 and the exhaust pump 1 in addition to the first shielding member 20 described above. Shielding plates 10 a and 10 b, a nozzle part shielding plate 24 disposed so as to cover the nozzle part 22, and shielding plates 15 a and 15 b respectively extending from the side wall of the chamber 2 toward the upper end of the vapor deposition region 60. The shielding plates 15a and 15b are arranged so as to cover the substrate 4, the first and second rolls 3 and 8 and the like that travel in the vapor deposition possible region other than the vapor deposition region 60 in the transport path of the substrate 4, and the vapor deposition material is provided on these. Prevent it from reaching. In addition, the shielding plates 15 a and 15 b allow the gas emitted from the plurality of emission ports provided on the side surface of the nozzle portion 22 to efficiently stay in the vapor deposition region 60 in the corresponding vapor deposition region 60.

  In addition, the conveyance part and shielding part in this embodiment are arrange | positioned with respect to the evaporation source 9 so that the vapor deposition material evaporated from the evaporation surface 9s may not enter into the board | substrate 4 from the normal line direction of the board | substrate 4 which drive | works a conveyance path | route. This makes it possible to perform deposition (oblique deposition) from a direction inclined from the normal direction of the substrate 4. In the thin film manufacturing apparatus 100 shown in FIG. 1, the first shielding members 20 and 22 and the nozzle part shielding plate 24 prevent the vapor deposition material from entering the substrate 4 from the normal direction of the substrate 4. Depending on the configuration of the transport unit, other shielding plates (for example, 15a and 15b) may have the same function.

The nozzle part 22 in the present embodiment is installed between the nozzle part shielding plate 24, the shielding plates 15 a and 15 b and the cooling can 6. The nozzle unit 22 is, for example, a tube extending along the width direction of the substrate 4 to be transported (direction perpendicular to the cross section shown in FIG. 1), and jets gas to the corresponding deposition region 60 on the side surface. A plurality of emission ports may be provided. Thereby, gas can be supplied substantially uniformly in the width direction of the substrate 4 in the vapor deposition region 60. Moreover, it is preferable that the nozzle part 22 is comprised so that a gas may be injected in parallel with each of the vapor deposition area | region 60. FIG. With such a configuration, the reaction rate between the oxygen gas emitted from the nozzle portion 22 and the vapor deposition particles can be increased, and a vapor deposition film with a high degree of oxidation can be formed without reducing the vacuum pressure in the chamber 2. .

  Next, the evaporation source 9 of the present embodiment will be described with reference to FIG. The evaporation source 9 contains a vapor deposition material in the container 16 and is heated by an electron beam 30 emitted from the electron gun 17 to form a thin film on the substrate.

  The evaporation source 9 is provided with a pipe 50 that can secure a passage from a part of a space for storing the vapor deposition material dissolved in the evaporation source 9 to the outside of the evaporation source 9 rather than the space. The tube 50 provided in the evaporation source 9 is preferably made of the same carbon material as that of the evaporation source 9.

  In this embodiment, the cylindrical tube shown in FIG. 3 (a) is used. However, it is sufficient if there is a space for securing a volume change when the vapor deposition material is cooled and expanded, for example, FIG. 3 (b). A prismatic shape as shown in FIG.

  FIG. 2A is a cross-sectional view of the evaporation source 9. FIG. 3A and FIG. 3B show examples of top views when cut along the AA plane in FIG.

<Operation of thin film manufacturing equipment>
Next, the operation of the thin film manufacturing apparatus 100 will be described. Here, a case where a plurality of active material bodies containing silicon oxide are formed on the surface of the substrate 4 using the thin film manufacturing apparatus 100 will be described as an example.

  First, a long substrate 4 (for example, 500 m) is wound around one of the first and second rolls 3 and 8 (here, the first roll 3), and the substrate 4 that has passed through the transport section is The substrate 4 is wound around one of the first and second rolls 3 and 8 (second roll 8 in this case) so as not to be unwound, and the substrate 4 is pulled and balanced with a force of 40N. As the substrate 4, a metal foil such as a copper foil or a nickel foil can be used. In order to dispose a plurality of active material bodies on the surface of the substrate 4 at a predetermined interval, it is necessary to use a shadowing effect by oblique vapor deposition. For this purpose, an uneven pattern is formed on the surface of the metal foil. It is preferable. In the present embodiment, as the uneven pattern, for example, a pattern in which square columnar protrusions having a rhombus (diagonal line: 20 μm × 10 μm) and a height of 10 μm are regularly arranged is used. The interval along the longer diagonal of the rhombus is 20 μm, the interval along the shorter diagonal is 10 μm, and the interval in the direction parallel to the sides of the rhombus is 10 μm. Further, the surface roughness Ra of the upper surface of each protrusion is set to 2.0 μm, for example.

  The crucible of the evaporation source 9 is preferably a carbon material that hardly reacts with silicon. A vapor deposition material (for example, silicon) is accommodated in the crucible of the evaporation source 9, and the gas introduction pipes 11 a and 11 b are connected to an oxygen gas cylinder or the like installed outside the thin film manufacturing apparatus 100. In this state, the chamber 2 is evacuated using the exhaust pump 1.

Next, the silicon in the crucible of the evaporation source 9 is heated by a heating device (not shown) such as an electron beam 30 heating device with the shutter 12 closed so that the evaporated particles do not reach the surface of the substrate 4. . After the heating conditions are set, the driving roller 7 is driven to feed out the substrate 4 wound around the first roll 3, and conveyance toward the second roll 8 is started. When the conveyance speed is stable (for example, 30 seconds), the shutter 12 is opened, and the evaporated particles are supplied to the surface of the substrate 4 passing through the first and second vapor deposition regions 60a and 60b. At the same time, oxygen gas is supplied from the nozzle portion 22 to the surface of the substrate 4 through the gas introduction pipe 11a and the gas introduction pipe 11b. Thereby, the compound (silicon oxide) containing silicon and oxygen can be grown on the surface of the substrate 4 by reactive vapor deposition. The substrate 4 after the silicon oxide is deposited on the surface in these deposition regions 60 a and 60 b is wound up by the second roll 8. The length measurement system 13 measures a desired length (for example, 400 m), closes the shutter 12, stops winding, and stops the substrate conveyance.

  Subsequently, when the substrate transport direction is reversed, the substrate transport direction can be reversed by reversing the rotation direction of the driving roller 7. When the conveyance speed is stabilized, the shutter 12 is opened again, and the evaporated particles are supplied to the surface of the substrate 4 passing through the first and second vapor deposition regions 60a and 60b.

  By performing vapor deposition while reversing the substrate transport direction as described above, an active material body having an arbitrary number n of layers can be continuously formed on the surface of the sheet-like substrate 4.

  When the predetermined vapor deposition is completed, the subsequent heating of the electron beam 30 is stopped.

  When heating of the electron beam 30 is stopped, cooling starts from the surface of the vapor deposition material (silicon) dissolved in the evaporation source 9 and the crucible side surface of the evaporation source 9. Therefore, the temperature inside the melted vapor deposition material is finally lowered.

  Here, when silicon as an evaporation material becomes a solid at around 1100 ° C., volume expansion of a volume expansion coefficient of about 1.13 times occurs due to phase transition.

  FIG. 4A shows a state in which the tube 50 is inserted into the evaporation source in a dissolved state, and FIG. 4B shows a state in which the heating of the electron beam 30 is stopped and the volume is expanded. Breaking and cracking the crucible of the evaporation source 9 can be suppressed by volume expansion and solidification in the volume expansion space formed by the tube 50.

  For example, the evaporation source 9 includes a cylindrical crucible (G347S manufactured by Tokai Carbon Co., Ltd.) having an outer diameter of Φ90 and a height of 40 in a water-cooled copper hearth, and having an outer diameter of Φ22, an inner diameter of Φ10, and a length of Φ70. At 120, a carbon tube having a hole of Φ10 at a position of length 10 and Φ10 opened at a position of length 10 are installed in the cylindrical crucible toward the center of the cylindrical crucible.

  As a vapor deposition material, 200 g of scrap silicon is charged in a cylindrical crucible at the same time.

The evacuation pump 1 evacuates the inside of the vacuum device, and the pressure is reduced to 1.0 × 10 ⁻³ Pa.
Using an electronic heating device (EBG 203 manufactured by JEOL Ltd.), the output of the electron beam 30 is increased from 1 kW to 5 kW over 60 minutes to dissolve the scrap silicon in the cylindrical crucible.

  The waveform of the electron beam 30 is widened so as to hit the entire surface of the scrap silicon charged and the Φ22 carbon tube protruding from the cylindrical crucible.

  After confirming the dissolution of scrap silicon, the output of the electron beam 30 is increased to 6 kW and deposition is performed for 60 minutes.

  Subsequently, the output of the electron beam 30 is lowered to 2 kW, and the waveform of the electron beam 30 is narrowed so that only the carbon tube is irradiated as shown in FIG.

  Thereafter, the electron beam 30 is stopped, cooled for 120 minutes, and opened to the atmosphere.

  The scrap silicon in the cylindrical crucible is solidified at a position that is 7 mm lower than the upper surface of the cylindrical crucible. In the carbon tube, the scrap silicon is solidified by rising 8 mm from the solidified position on the cylindrical crucible, and the cylindrical crucible can be maintained without cracking.

  Although the operation of the thin film manufacturing apparatus 100 has been described by taking as an example the case of forming an active material body made of silicon oxide, the use of the vapor deposition material to be used and the obtained vapor deposition film is not limited to this example. In the above description, the vapor deposition material (silicon atoms) evaporated by the evaporation source 9 and the gas (oxygen gas) supplied from the nozzle unit 22 are reacted to form a vapor deposition film, but the gas is not supplied. In addition, only the vapor deposition material may be grown on the surface of the substrate 4.

(Embodiment 2)
Next, a second embodiment of a thin film manufacturing apparatus and a thin film manufacturing method according to the present invention will be described with reference to FIGS.

  In this embodiment, for the sake of simplicity, the same components as those in Embodiment 1 are denoted by the same reference numerals, and the description thereof is omitted.

  First, referring to FIG. In the present embodiment, in addition to the configuration of the first embodiment, a driving device 18 that can attach and detach the tube 50 to and from the vapor deposition container 16 is further provided.

  As shown in FIG. 6, the drive device 18 can be installed in the evaporation source 9 or removed from the evaporation source 9 by grasping the tube 50.

  By having such a configuration, the tube 50 can be inserted into the vapor deposition vessel 16 after the vapor deposition is completed, which is preferable because vapor deposition is not affected.

  In this case, the place where the tube 50 is inserted is not particularly limited as long as it is in the evaporation source 9.

  Subsequently, a preferable method for manufacturing a thin film in the present embodiment will be described with reference to FIGS.

  As shown in FIG. 7A, the electron gun 17 irradiates the deposition material with an electron beam 30 to form a thin film on the substrate 4.

After the vapor deposition is completed, the tube 50 is inserted using the driving device 18 so that the lower side of the vapor deposition material is communicated with the upper side of the melt surface. (Fig. 7 (b) (c))
As described above, it is preferable to insert the tube 50 into the evaporation source 9 immediately after the heating of the electron beam 30 is stopped after the vapor deposition is completed, because the vapor deposition is not affected. Further, the place where the tube 50 is inserted is not particularly limited as long as it is in the evaporation source 9.

  Subsequently, the electron beam 30 is irradiated onto the tube 50, the tube 50 is kept at about 1400 ° C., the electron beam 30 irradiating the surface of the vapor deposition material is stopped, and the vapor deposition material in the vapor deposition container 16 is cooled ( FIG. 7 (d)). After the vapor deposition material in the container 16 changes from the liquid phase to the solid phase, the electron beam 30 applied to the tube 50 is stopped, and the vapor deposition material in the communication path of the tube 50 is cooled.

  In this manner, by sequentially cooling the vapor deposition material in the vapor deposition vessel 16-the tube 50, a space for volume expansion due to the vapor deposition material in the vapor deposition vessel 16 changing to a solid phase is ensured, and then in the tube 50. The evaporation material can be changed to a solid phase.

By using the thin film manufacturing apparatus and the thin film manufacturing method as described above, the vapor deposition container 16 can be prevented from cracking and being damaged, whereby the frequency of vapor deposition container replacement can be reduced and the vapor deposition cost can be reduced.

  A more preferable thin film manufacturing method will be described with reference to FIG.

  After the cooling of the evaporation source 9 is completed, it is released to the atmosphere, a vapor deposition material is replenished and added to the evaporation source 9, and evacuation is performed after completion of predetermined cleaning and substrate preparation (FIG. 8A). When the predetermined degree of vacuum is reached, heating of the electron beam 30 is started, and the vapor deposition material is dissolved again (FIG. 8B). When the vapor deposition material is dissolved, the tube 50 is taken out from the evaporation source 9 (FIG. 8C), and vapor deposition is performed on the substrate.

  By forming a thin film by such a method, the tube 50 can be removed from the evaporation source before the start of vapor deposition, so that vapor deposition can be performed without being affected by the tube 50.

In addition, the vapor deposition film formed on the current collector substrate by the thin film manufacturing method of the present invention can be used as a negative electrode active material of a lithium ion secondary battery when the vapor deposition material is silicon or tin, and LiCoO ₂ or LiNiO _2. , LiMn ₂ O ₄ and other commonly used positive electrode plates containing a positive electrode active material, a separator made of a microporous film, and lithium hexafluorophosphate such as ethylene carbonate and propylene carbonate. A lithium ion secondary battery can be easily produced by using together with an electrolyte solution having a lithium ion conductivity of a generally known composition dissolved in a kind.

  In this embodiment, silicon is used as the vapor deposition material, and a carbon material is used as the vapor deposition raw material container and the tube. However, such a combination is preferable because the reaction rate between the vapor deposition material and the vapor deposition raw material container and between the vapor deposition material and the pipe is small. . On the other hand, the ceramic material as in Patent Document 3 cannot be preferably used because of its high reaction rate with silicon.

  In addition, the deposited film produced by the thin film production apparatus of the present invention can suppress the destruction of the active material particles accompanying the expansion of the active material, and has various shapes such as a cylindrical shape, a flat shape, a coin shape, and a square shape. The present invention can be applied to an electrolyte secondary battery, and the shape and sealing form of the battery are not particularly limited.

  In the thin film manufacturing apparatus and thin film manufacturing method of the present invention, the evaporation material can be reliably taken out in the molten state while irradiating the electron beam from the crucible after film formation. Therefore, film formation can be performed stably at low cost.

  In particular, the present invention is particularly effective when a carbon crucible and a silicon material are used, in which the crucible is easily broken and the influence of the crucible cost is great, and further, a large stress is generated when the material is solidified.

DESCRIPTION OF SYMBOLS 1 Exhaust pump 2 Chamber 3, 8 Unwinding or winding roll 4 Substrate 5a-5f Conveyance roller 6 Cooling can 7 Drive roller 9 Evaporation source 9s Evaporation surface 10a, 10b Shielding plate 11a, 11b Gas introduction pipe 12 Shutter 13 Measurement system 15a to 15c Shielding plate 16 Evaporating container 17 Electron gun 18 Driving device 20a, 20b Shielding member 22 Nozzle part 24 Nozzle part shielding plate 30 Electron beam 50 Tube 60a, 60b Deposition area 100 Thin film manufacturing apparatus

Claims (10)

A thin film manufacturing apparatus for forming a film on the surface of a substrate using vacuum deposition,
Vapor deposition raw material;
A container containing the vapor deposition raw material;
Heating means for heating the vapor deposition material housed in the container;
When the heating means heats the vapor deposition raw material and melts, a pipe communicating below the melting surface of the vapor deposition raw material and above the melting surface;
A thin film manufacturing apparatus.   The thin film manufacturing apparatus according to claim 1, wherein the tube is inserted after the vapor deposition material is dissolved.   The thin film manufacturing apparatus according to claim 1, wherein the heating unit is an electron beam irradiation unit.   The thin film manufacturing apparatus according to claim 1, wherein the vapor deposition material includes at least silicon, and the container includes a carbon material as a main component. The thin film manufacturing apparatus according to claim 4, wherein the pipe is made of a carbon material. A method of manufacturing a thin film that forms a film on a surface of a substrate using vacuum deposition,
A step (A) of heating and dissolving the vapor deposition material;
(B) inserting a tube communicating below the melting surface of the vapor deposition material and above the melting surface into a container for dissolving the vapor deposition material;
And (C) a step of cooling the vapor deposition material.   The method for producing a thin film according to claim 6, wherein the tube is inserted after the deposition raw material is dissolved.   The thin film manufacturing method according to claim 6, wherein the tube inserted into the container is irradiated with an electron beam.   The manufacturing method of the thin film of Claim 6 whose said vapor deposition raw material is a silicon | silicone and the said container is a carbon material. The thin film manufacturing apparatus according to claim 9, wherein the pipe is made of a carbon material.