JPWO2018199184A1 - Evaporation source and film forming apparatus - Google Patents

Abstract

The evaporation source comprises an evaporation source container, a heating device, a first heat shield and a second heat shield. The evaporation source container has a top surface, a container body containing a thin film material, and a plurality of nozzles connected to the container body and projecting from the top surface to be uniaxially disposed and having an opening for discharging a vaporized material of the thin film material And The heating device heats the container body. The first heat shield plate is disposed to face the top surface at a distance, and has a plurality of first opening regions larger than the openings of the nozzles through which the nozzles provided corresponding to the plurality of nozzles pass. A first opening is provided. The second heat shield plate is fixed to each of the plurality of nozzles between the container main body and the first heat shield plate and is disposed to face the top surface at a distance from the top surface, and has an outer shape larger than the first opening region. The nozzle has a second opening through which it passes.

Description

  The present invention relates to an evaporation source for evaporating a thin film material and releasing a vaporized substance, and a film forming apparatus provided with the evaporation source.

  For example, in forming a thin film used for an electronic device such as an organic EL display device, a vacuum is made to heat and evaporate the thin film material and attach the vaporized substance (vapor) of the thin film material to a film forming object such as a glass substrate A vapor deposition apparatus is used. In recent years, as an evaporation source capable of coping with the increase in size of a film formation target, a linear source has been proposed in which a plurality of nozzles for emitting vaporized material of thin film material are arranged in a single row (see, for example, Patent Document 1). Such an evaporation source is provided with a heat shielding member such as a reflector so that radiation heat generated to heat the thin film material is not radiated to the outside of the evaporation source.

  A linear source type evaporation source is configured by arranging and connecting a plurality of nozzles in a row to an evaporation source container that contains thin film material, and has an elongated rectangular parallelepiped shape. The film formation target is disposed opposite to the surface on which the nozzle of the linear evaporation source is disposed, and the vaporized substance of the thin film material heated by a heating device such as a heater is discharged from the nozzle and attached to the film formation target. Film formation is performed. The heat shielding member is disposed between the film formation target and the evaporation container, but the heat shielding member is not disposed in the vicinity of the nozzle.

JP, 2012-146658, A

  In the evaporation source having the above configuration, radiation heat from the evaporation source heated by the heater or the heater is emitted to the outside of the evaporation source through the vicinity of the nozzle where the heat shielding member is not disposed, and the deposition target is The temperature of the film formation target is increased. When the temperature of the film forming object is high, the vaporized material of the thin film material which has reached the film forming object moves around the film forming object and does not adhere well, and re-evaporation causes the film formation to be unsuccessful. There's a problem. In addition, in the case of forming a thin film on a film formation target through a metal mask, the metal mask is expanded by radiant heat, and there is a problem that a thin film having a desired pattern can not be obtained. In particular, in the case of forming a thin film of high definition pattern using a metal mask, for example, when the film formation target is a substrate constituting a display device due to the positional deviation of the film formation pattern due to the expansion of the metal mask. It greatly affects the display characteristics.

  In view of the circumstances as described above, an object of the present invention is to provide an evaporation source capable of reducing radiation heat emitted from an evaporation source and a film forming apparatus provided with the evaporation source.

In order to achieve the above object, an evaporation source according to an aspect of the present invention includes an evaporation source container, a heating device, a first heat shielding plate, and a second heat shielding plate.
The evaporation source container includes a container main body having a top surface and containing a thin film material, and an opening for connecting to the container main body, projecting from the top surface and disposed in a uniaxial direction, and releasing a vaporized substance of the thin film material And a plurality of nozzles.
The heating device heats the container body.
The first heat shield plate is disposed to face the top surface at a distance from the top surface, and a first opening area larger than the opening of the nozzle through which the nozzle provided corresponding to each of the plurality of nozzles penetrates And a plurality of first openings.
The second heat shield plate is fixed to each of the plurality of nozzles between the container body and the first heat shield plate, and is disposed opposite to the top surface so as to face the top surface, and the first opening region The nozzle has a second opening which has a larger profile and through which the nozzle passes.

  According to such a configuration of the present invention, the second heat shield plate is configured to have an outer shape larger than the first opening region corresponding to the first opening of the first heat shield plate. Therefore, radiation heat that can not be shielded by the first heat shielding plate through the first opening among radiation heat generated by heating by the heating device can be reduced by the second heat shielding plate. This reduces the radiant heat emitted from the evaporation source. Therefore, the heating by the radiant heat from an evaporation source of the film-forming object in which thin film material is formed into a film is suppressed, and a favorable film-forming can be performed. Further, in the case of forming a film through a metal mask, expansion due to heating of the metal mask can be suppressed, and film formation of a high definition pattern becomes possible.

The second heat shield plate may be fixed to the nozzle by point contact.
According to such a configuration, since the contact area between the nozzle and the second heat shield plate can be reduced, the cooling of the nozzle by the second heat shield plate can be suppressed. Thereby, the cooling of the vaporized substance of the thin film material passing through the inside of the nozzle is suppressed, and the nozzle clogging can be prevented.

The first opening may have a shape having a longitudinal direction in the uniaxial direction.
According to such a configuration, even if the container body expands due to the heating of the heating device and the positional displacement of the nozzle connected to the container body occurs as the container body extends in one axial direction, the first opening is always generated. The nozzle can be configured to be located in the unit.

From the opening of the nozzle, which is disposed between the evaporation source container and the second heat shielding plate and is opposed to the top surface, and which is provided corresponding to each of the plurality of nozzles. It may further comprise a third heat shield provided with a plurality of third openings having a large third opening area.
Thus, radiant heat can be efficiently reduced by providing the third heat shield plate.

  The first heat shield plate has an outer shape which surrounds the evaporation source container having a top surface having the first opening and a bottom surface facing the top surface, and the container main body includes the heating. It may be supported by the bottom portion so as to be movable in the uniaxial direction according to the amount of extension in the uniaxial direction of the container body due to thermal expansion of the container body due to heating of the device.

  According to such a configuration, even if the container body is expanded due to thermal expansion, the evaporation source container is moved in one axial direction by the movable support portion according to the amount of expansion, so distortion does not occur in the container body. Thus, the amount of the vaporized substance of the thin film material emitted from the evaporation source can be made uniform in the plane. In film formation using such an evaporation source, it is possible to form a thin film having a uniform film thickness in the plane.

A film forming apparatus according to an embodiment of the present invention includes a housing portion and an evaporation source.
The storage unit can store a film formation target.
The evaporation source is connected to the container body having a top surface and containing a thin film material, and is connected to the container body and protrudes uniaxially from the top surface, and the evaporation material of the thin film material is the film forming object. An evaporation source container provided with a plurality of nozzles having an opening for discharging toward the other, a heating device for heating the container body, and the top surface spaced apart and disposed to correspond to each of the plurality of nozzles A first heat shielding plate comprising a plurality of first openings having a first opening area larger than the opening of the nozzle through which each of the nozzles penetrates; the container body and the first heat shielding A plurality of nozzles are fixed to each of the plurality of nozzles between the plate and spaced apart from the top surface so as to face each other, and has a second opening which has an outer shape larger than the first opening area and through which the nozzles penetrate And a second heat shield plate.

  As described above, according to the present invention, it is possible to obtain an evaporation source and a film forming apparatus capable of reducing the radiation heat emitted from the evaporation source.

It is a schematic cross section of the film-forming apparatus which concerns on the 1st Embodiment of this invention. It is a model top view of the evaporation source provided in the said film-forming apparatus. It is the partial expansion perspective view of nozzle vicinity of the said evaporation source. FIG. 4 is a partial enlarged perspective view of the vicinity of a nozzle of the evaporation source shown in FIG. 3 as viewed from a direction from the bottom to the top of a water-cooled plate. It is the partial top view which shows the mode before and behind the heating in the nozzle vicinity in the said evaporation source, and sectional drawing corresponding to it. It is the partial enlarged perspective view of the nozzle vicinity of the evaporation source which concerns on the 2nd Embodiment of this invention, and a partial expanded sectional view. It is a partial top view and a corresponding sectional view showing a situation before and after heating near a nozzle in a conventional evaporation source.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the drawings, the X-axis direction and the Y-axis direction indicate horizontal directions orthogonal to each other, and the Z-axis direction indicates a height direction orthogonal to these.

First Embodiment
[Configuration of film forming apparatus]
FIG. 1 is a schematic cross-sectional view of a film forming apparatus according to an embodiment of the present invention.
The film forming apparatus 1 includes a vacuum chamber 2 as a storage unit, a linear source type evaporation source 3 disposed on the bottom side inside the vacuum chamber 2, and a substrate holder 8 as a holding unit for holding a film formation target. The vacuum exhaust system 7, the film thickness sensor 6, the temperature measurement sensor 10, the controller 4, and the power supply 5 are provided.

The vacuum chamber 2 accommodates a glass substrate 9 as a film formation target.
The substrate holder 8 is disposed on the top surface side inside the vacuum chamber 2. The substrate holder 8 holds the surface (film formation target surface) 9 a on which the glass substrate 9 as a film formation target is to be formed into a film formation downward. The linear source type evaporation source 3 has a substantially rectangular parallelepiped outer shape having a longitudinal direction in the X-axis direction. The substrate holder 8 is configured to be movable in a direction (Y-axis direction) orthogonal to the longitudinal direction (X-axis direction) of the evaporation source 3.

The evaporation source 3 accommodates the thin film material (evaporation material) 36, heats and evaporates the thin film material 36, and releases the vaporized substance (vapor) of the thin film material 36. Details of the evaporation source 3 will be described later.
The vacuum evacuation system 7 is connected to the vacuum chamber 2. The evacuation system 7 evacuates the inside of the vacuum chamber 2 to form a vacuum atmosphere suitable for film formation.

  In the film forming apparatus 1, the evaporation atmosphere of the thin film material 36 is released from the evaporation source 3 while maintaining the vacuum atmosphere of the vacuum chamber 2 and moving the glass substrate 9 while holding the glass substrate 9 by the substrate holder 8. A vaporizing substance is deposited on the film formation target surface 9 a to form a desired thin film on the glass substrate 9.

  In the present embodiment, the glass substrate 9 is movable, but the position of the glass substrate 9 may be fixed, and the evaporation source 3 may be movable in the Y-axis direction. In addition, without moving the glass substrate 9 or the evaporation source 3, film formation may be performed in a state where the glass substrate 9 and the evaporation source 3 are fixed. Moreover, although a glass substrate is mentioned as an example and demonstrated as a film-forming target object in this embodiment, it is not limited to this, A flexible film base material etc. may be used.

The temperature measurement sensor 10 is connected to the controller 4 and measures the temperature of the evaporation source case 35 of the evaporation source 3 described later.
The film thickness sensor 6 measures the amount of vapor (vaporized substance) from the evaporation source 3 and controls the thickness (or film formation rate) of the thin film formed on the glass substrate 9. The film thickness sensor 6 is disposed so as not to prevent the vaporized substance of the thin film material emitted from the evaporation source 3 from reaching the glass substrate 9. The output of the film thickness sensor 6 is input to the controller 4.

  The controller 4 adjusts the amount of electric power supplied to the heater 34 as a heating device provided in the evaporation source 3 described later based on the measurement results of the film thickness sensor 6 and the temperature measurement sensor 10 as an evaporation source container. The evaporation source case 35 is brought to a desired temperature, and the amount of vapor (vaporized substance) to be released or the deposition rate is controlled to a desired value.

Next, the evaporation source 3 will be described.
[Configuration of evaporation source]
The evaporation source 3 will be described using FIGS. 1 to 4.
FIG. 2 is a schematic top view of the evaporation source 3. FIG. 3 is a partially enlarged perspective view of the vicinity of the nozzle of the evaporation source 3. FIG. 4A is a perspective view of the vicinity of the nozzle of the evaporation source 3 in FIG. 3 and is a partially enlarged perspective view seen from the direction from the bottom surface portion 313 to the top surface portion 310 of the water cooling plate 31 described later. FIG. 4B is a further enlarged perspective view of FIG. 4A.

  As shown in FIG. 1, the evaporation source 3 which is a linear source type evaporation source includes an evaporation source case 35 as an evaporation source container, a heater 34 as a heating device, and a water cooling plate 31 as a first heat shielding plate. , A follow-up reflector 33 as a second heat shielding plate, a reflector 32 as a third heat shielding plate, a fixed support 391, and a movable support 392.

  The heater 34 heats the evaporation source case 35. The thin film material 36 contained in the evaporation source case 35 is heated by the heater 34 to be a vaporized substance of the thin film material 36. The heater 34 is disposed between the evaporation source case 35 and the reflector 32 so as to surround the entire evaporation source case 35. The heater 34 is typically comprised of a resistive heating wire, but may be comprised of an induction heating coil.

  The evaporation source case 35 has a container body 351 and a plurality of nozzles 37.

  The container main body 351 has a top surface 352 and accommodates the thin film material 36. The container main body 351 has a rectangular parallelepiped outer shape, and its top surface 352 is a surface parallel to the XY plane. The evaporation source case 35 and the substrate holder 8 are provided such that the top surface 352 and the film formation target surface 9 a of the glass substrate 9 are spaced apart and opposed in the Z-axis direction. The container main body 351 is made of a highly thermally conductive material such as metal or graphite.

  The plurality of nozzles 371 to 377 project from the top surface 352 of the container main body 351 and are disposed in connection with the container main body 351. The plurality of nozzles 371 to 377 are arranged in a line in one axial direction (drawing X axis direction). In FIG. 2, the nozzles 371, the nozzles 372, the nozzles 373, the nozzles 374, the nozzles 375, the nozzles 376, and the nozzles 377 are disposed in order from left to right in FIG. 2. The nozzles 371 to 377 will be collectively referred to as a nozzle 37, and will be described using the reference numerals 371 to 377 as necessary.

  The nozzle 37 has an opening (vaporized substance discharge port) 380 for discharging the vaporized substance of the thin film material 36. The vapor of the thin film material 36 generated in the container body 351 is discharged from the opening 380 into the vacuum chamber 2 which is outside the evaporation source 3.

  The plurality of nozzles 371 to 377 are connected to a common container body 351. For the nozzle 37, a material such as tantalum, molybdenum or carbon can be used. The container body 351 has an elongated rectangular parallelepiped shape having a longitudinal direction in the X-axis direction in which the nozzles 37 are arranged. The nozzle 37 has a cylindrical shape having a substantially circular cross section perpendicular to the Z-axis direction, but the shape of the nozzle 37 is not limited to this.

  The water cooling plate (first heat shielding plate) 31 has a heat shielding function of performing water cooling and cooling. The water cooling plate 31 is provided with a water channel such as a water cooling pipe in which water flows. The water cooling plate 31 is provided to absorb and reduce radiation heat radiated from the evaporation source case 35 heated by the heater 34 and the heater 34 to the glass substrate 9.

  The water cooling plate 31 has a rectangular parallelepiped outer shape having a top surface portion 310, a bottom surface portion 313 facing the top surface portion 310, and a side surface portion 314, and the water cooling plate 31 constitutes the outer shape of the evaporation source 3. The water cooling plate 31 is disposed so as to surround the evaporation source case 35, the heater 34, the reflector 32, and the follow reflector 33. The top surface portion 310 of the water cooling plate 31 is disposed substantially in parallel with the XY plane, and is disposed to face the top surface 352 of the container main body 351 of the evaporation source case 35 while being separated therefrom.

  The top surface portion 310 of the water cooling plate (first heat shielding plate) 31 is provided with a plurality of first openings 311 to 3117. The first opening 3111 is a nozzle 371, the first opening 3112 is a nozzle 372, the first opening 3113 is a nozzle 373, the first opening 3114 is a nozzle 374, and the first opening 3115. The first opening 3116 is provided corresponding to the nozzle 376, and the first opening 3117 is provided corresponding to the nozzle 377. Hereinafter, the first openings 3111 to 3117 will be collectively referred to as the first opening 311, and the explanation will be made using the reference numerals 3111 to 3117 as necessary.

  The first opening 311 is provided for each nozzle 37 so that the corresponding nozzle 37 penetrates. The first opening 311 has a first opening area larger than the opening 380 of the nozzle 37.

  When the nozzle 37 is cooled, the vaporized substance of the thin film material passing through the nozzle 37 is cooled in the nozzle 37, which may cause the nozzle 37 to be clogged. Therefore, the first opening 311 is provided so that the water cooling plate 31 and the nozzle 37 do not come in contact with each other so that the nozzle 37 is not clogged.

  The planar shape of the first opening 311 has a longitudinal direction in the X-axis direction in which the plurality of nozzles 37 are arranged. In the present embodiment, the first opening 311 has a substantially elliptical or oval shape having a long axis along the X-axis direction and a short axis along the Y-axis direction, but the shape is not limited to this. For example, it may be rectangular.

  In the evaporation source 3 of the linear source type having an elongated rectangular parallelepiped shape having a structure in which the plurality of nozzles 37 are arranged in a common container body 351 in a uniaxial direction, the container body 351 is heated by the heater 34 during film formation. The position of the nozzle 37 connected to the container main body 351 may be displaced by several mm from the normal temperature due to thermal expansion and expansion in the longitudinal direction (arrangement direction of the nozzles). The first opening 311 is formed in consideration of the positional displacement amount of the nozzle 37. That is, even if positional deviation of the nozzle 37 occurs due to thermal expansion, the first opening 311 is in the longitudinal direction of the container main body 351, which is the extension direction, so that the nozzle 37 is positioned in the first opening 311. It has a shape having a longitudinal direction.

  Further, in the container body 351 that expands due to heating, the amount of positional deviation of the nozzle 37 accompanying thermal expansion increases from the center to the end along the longitudinal direction (X-axis direction) of the evaporation source case 35 To go.

  Specifically, even if the evaporation source case 35 is thermally expanded and stretched due to heating, the position of the nozzle 374 located at the central portion of the evaporation source case 35 hardly changes from the position before heating. On the other hand, the positions of the nozzles 371 to 373 and 375 to 377 change with the thermal expansion of the evaporation source case 35 due to heating. Among the nozzles 371 to 373 and 375 to 377, the nozzles 371 and 377 located closest to both ends of the evaporation source case 35 have the largest change in position, followed by the largest change in the positions of the nozzles 372 and 376 , The change in the position of the nozzles 373 and 375 is the smallest.

  As described above, the amount of positional deviation of the nozzle 37 due to heating at the time of film formation differs depending on the position where the nozzle 37 is disposed. The plurality of first openings 311 are formed such that the nozzles 37 are positioned within the first openings 311 even if the positional deviation occurs due to thermal expansion, taking into consideration the difference in the amount of positional deviation due to the arrangement of the nozzles 37. Be done.

  FIG. 2 is a schematic top view of the evaporation source 3 at normal temperature. As shown in FIG. 2, in the evaporation source 3 before film formation, the nozzle 374 positioned at the center of the evaporation source case 35 is positioned substantially at the center of the corresponding first opening 3114. On the other hand, the nozzles 375 to 377 located on the right side in the drawing from the central part of the evaporation source case 35 are located on the left side in the corresponding first openings 3115 to 3117. On the other hand, the nozzles 371 to 373 located on the left side in the drawing from the central part of the evaporation source case 35 are located on the right side in the corresponding first openings 3111 to 3113.

  At the time of film formation, when the evaporation source container 3 is heated, the evaporation source case 35 thermally expands and expands, and the position of the nozzles 37 changes accordingly, the respective nozzles 371 to 377 correspond to the corresponding first The first openings 3111 to 3113 are arranged so as to be located substantially at the center of the openings 3111 to 3117.

  In the present embodiment, the tip of the nozzle 37 and the upper surface 31 a of the top surface 310 of the water-cooled plate (first heat shield plate) 31 are located on the same XY plane, but not limited thereto. For example, the nozzle 37 may protrude from the top surface 31 a from the water cooling plate 31 through the first opening 311.

  The reflector (third heat shield plate) 32 is disposed to surround the heater 34 and the evaporation source case 35. The reflector 32 is disposed between the water cooling plate 31 and the heater 34. The top surface portion of the reflector 32 disposed opposite to the top surface portion 310 of the water cooling plate 31 is spaced apart from the top surface 352 of the container main body 35, disposed opposite to each other, and disposed parallel to the XY plane.

  The reflector 32 is configured by laminating three single reflectors 321, 322, and 323 separately from each other. The reflector 32 is provided to reduce radiant heat that reaches the glass substrate 9 from the heater 34 and the evaporation source case 35 heated by the heater 34. By providing a plurality of single reflectors 321 to 323, the amount of heat of radiant heat reaching the water cooling plate 31 can be reduced stepwise. Aluminum, stainless steel, molybdenum, tantalum or the like can be used for the reflector.

  For example, when using silver as a thin film material to generate silver vapor, it is necessary to heat the silver to about 1100 ° C. When only the water cooling plate 31 is used as a heat shielding plate, the water flowing in the water cooling plate 31 boils. In some cases, the water cooling plate 31 can not exhibit a sufficient cooling function (heat shielding function).

  On the other hand, by disposing the reflector 32 between the water cooling plate 31 and the evaporation source case 35, the radiant heat from the evaporation source case 35 heated by the heater 34 and the heater 34 is 900 ° C. by the single reflector 321, for example. The temperature is reduced stepwise by the single reflector 322 to 500 ° C. and 300 ° C. by the single reflector 323, and when reaching the water cooling plate 31, the radiation heat is sufficiently reduced. Thus, radiant heat can be efficiently reduced by using a plurality of heat shielding means.

  The reflector 32 has a plurality of third openings 324 through which the nozzles 37 provided corresponding to the nozzles 37 pass. The third opening 324 has a third opening area larger than the opening 380 of the nozzle 37. Similar to the first opening 311 of the water cooling plate 31, the third opening 324 is provided in consideration of the positional deviation of the nozzle 37 due to the thermal expansion of the container body 351. Similar to the water cooling plate 31, the reflector 32 is provided with a third opening 324 so that the reflector 32 and the nozzle 37 do not contact in order to prevent nozzle clogging. The third opening 324 has a substantially elliptical or oval planar shape having a long axis along the X-axis direction and a short axis along the Y-axis direction.

  As shown in FIG. 2, the length a of the evaporation source 3 in the longitudinal direction (X-axis direction) is, for example, about 30 cm to 3 m, and the number of nozzles 37 and the evaporation source 3 depend on the size of the film forming object and the film forming pattern. The longitudinal length a of is determined.

  The major diameter c of the first opening 311 provided in the top surface portion 310 of the water cooling plate 31 is 20 mm, and the minor diameter e is 12 mm. The outer diameter d of the nozzle 37 is 10 mm, and the pitch (distance between centers of adjacent nozzles) b of the nozzles 37 is 10 mm to 25 mm.

  The number and arrangement position of the nozzles 37 can be set arbitrarily. For example, the nozzles 37 may be arranged such that the pitch of the nozzles 37 arranged at the end of the evaporation source 3 is dense, whereby a uniform film can be formed in the substrate surface. In the present embodiment, for convenience, the number of the nozzles 37 is seven and the pitch of the nozzles 37 is illustrated to be uniform.

  As shown in FIGS. 1 to 4, the following reflectors (second heat shielding plates) 331 to 337 are fixed to the nozzles 371 to 377 corresponding to the plurality of nozzles 371 to 377, respectively. The follow-up reflectors 331 to 337 are provided separately from one another.

The tracking reflector 331 follows the nozzle 371, the tracking reflector 332 follows the nozzle 372, the tracking reflector 333 follows the nozzle 373, the tracking reflector 334 follows the nozzle 374, the tracking reflector 335 follows the nozzle 375, and the tracking reflector 335 follows the nozzle 375. Reference numeral 336 is fixed to the nozzle 376, and the tracking reflector 337 is fixed to the nozzle 377.
Hereinafter, the follow-up reflectors 331 to 337 will be collectively referred to as the follow-up reflector 33, and will be described using the reference numerals 331 to 337 as necessary.

  Since the follow-up reflector 33 is fixed to the nozzle 37, even if the position of the nozzle 37 changes due to the thermal expansion of the container main body 351, the position of the follow-up reflector 33 changes accordingly.

  The follow-up reflector 33 is disposed between the top surface portion 310 of the water-cooling plate 31 and the reflector 32 in the Z-axis direction, separately from the top surface portion 310 and the reflector 32. The follow-up reflector 33 is disposed to face the top surface 352 separately from the top surface 352.

  The follow-up reflector 33 has an outer shape larger than the first opening area of the first opening 311 of the water cooling plate 31. The follow-up reflector 33 has a substantially rectangular plate shape having a horizontal length of 40 mm parallel to the X-axis direction and a vertical length 25 mm parallel to the Y-axis direction. The plurality of follow-up reflectors 331 to 337 are disposed apart from each other on the same XY plane. The distance between adjacent tracking reflectors 33 is 5 mm, for example. Even if the position of the nozzle 37 fluctuates due to the thermal expansion of the container main body 351 and the position of the tracking reflector 33 fluctuates following this, the distance between the adjacent tracking reflectors 33 is such that adjacent tracking reflectors do not contact with each other. It is set.

  At a substantially central portion of the follow-up reflector 33, a second opening 330 through which the corresponding nozzle 37 passes is provided. The second opening 330 has a substantially circular planar shape, and the open end thereof is formed with three protrusions 38 projecting toward the center of the second opening 330. The three protrusions 38 are equally spaced from one another.

  The projecting portion 38 has an acute angle portion 38a, and the three reflectors 38 are fixed to the nozzle 37 by supporting the nozzle 37 at three points by three acute angle portions 38a. In the present embodiment, the follow-up reflector 33 is fixed to the nozzle 37 by three-point support, but the number of support points is not limited to three.

In the present embodiment, the same cylindrical nozzle 37 is taken as an example regardless of which XY plane the cross section cut in the direction perpendicular to the Z-axis direction is cut, but the present invention is not limited thereto.
For example, it is possible to use a tubular shape having a tapered outer shape in which the cross-sectional shape continuously cut in the direction perpendicular to the Z-axis direction in the Z-axis direction becomes larger. Then, by forming the nozzle 37 having a tapered outer shape such that the opening 380 for releasing the vaporized substance of the thin film material 36 to the outside of the evaporation source 3 is smaller than the opening on the side connected to the container main body 351. When assembling the second opening 330 of the follow-up reflector 33 through the nozzle 37, positioning of the follow-up reflector 33 in the Z-axis direction is facilitated.
Further, in the present embodiment, the nozzle is attached to the top surface of the evaporation source case so that the longitudinal direction is perpendicular to the top surface, but the nozzle may be attached obliquely to the top surface at an angle.

  When the water cooling plate (first heat shielding plate) 31, the follow-up reflector (second heat shielding plate) 33, and the reflector (third heat shielding plate) 32 are projected onto the top surface 352, the first of the water cooling plates 31 is The opening area (first opening 311) and the third opening area (third opening 324) of the reflector 32 substantially overlap each other. Then, the first opening 311 and the third opening 324 are formed so that the nozzle 37 is located inside the first opening area and the third opening area.

  Furthermore, the water cooling plate 31, the reflector 32, and the tracking reflector 33 are arranged such that the first opening region and the third opening region overlapping each other are located within the rectangular outline projection region of the tracking reflector 33. . In the positional relationship that the first opening area and the third opening area are located in the projection area of the outline of the follow-up reflector 33, the position of the nozzle 37 is changed due to the thermal expansion of the container body 351 due to heating during film formation. The tracking reflector 33 is arranged to be maintained even in the case.

  The evaporation source case 35 is supported by the fixed support portion 391 and the movable support portion 392 on the bottom surface portion 313 of the water cooling plate 31 having a rectangular parallelepiped shape. In addition, although it was set as the rectangular parallelepiped water-cooling board in this embodiment, a shape is not limited to this. In order to block the arrival of the radiation heat from the evaporation source case 35 heated by the heater 34 and the heater 34 to the film formation object (the glass substrate in the present embodiment) 9, the film formation object 9 and the heater 34 surround At least the water-cooling plate may be disposed between the evaporation source case 35 and the discharge source case 35.

  The fixed support portion 391 has a shape having a longitudinal direction in the Y-axis direction. The fixed support portion 391 is disposed between the bottom surface of the evaporation source case 35 and the bottom surface portion 313 of the water cooling plate 31 in the central portion of the evaporation source case 35. A part of the bottom surface of the evaporation source case 35 is installed and fixed to the bottom surface portion 313 of the water cooling plate 31 by the fixed support portion 391. As described above, the fixed support portion 391 is disposed at the central portion of the evaporation source case 35 which hardly causes positional deviation due to extension even if thermal expansion of the container main body 351 occurs due to heating during film formation.

  The movable support portion 392 is disposed between the bottom surface of the evaporation source case 35 and the bottom surface portion 313 of the water cooling plate 31. The movable support portions 392 are disposed to face each other in the vicinity of both end portions in the longitudinal direction of the evaporation source case 35 with the fixed support portion 391 as a boundary.

  The movable support portion 392 is installed and fixed to the bottom surface of the evaporation source case 35, and is configured to be movable on the bottom surface portion 313 of the water cooling plate 31. The movable support portion 392 is movably provided in the X-axis direction in accordance with the amount of extension of the container body 351 in the X-axis direction due to the thermal expansion of the container body 351 due to the heating of the heater 34. For example, a pipe roller having a major axis direction in the Y-axis direction can be used as the movable support portion 392. The pipe roller can be rotatably installed and fixed to the bottom surface of the evaporation source case 35 so that the pipe roller can be moved along the X-axis direction on the bottom surface portion 313 of the water cooling plate 31.

  As described above, the evaporation source case 35 is supported by the bottom surface portion 313 of the water cooling plate 31 via the fixed support portion 391 and the movable support portion 392. The fixed support 391 and the movable support 392 are provided with their heights adjusted so that the evaporation source case 35 is held horizontally.

  Thus, by providing the fixed support portion 391 and the movable support portion 392, even if the container main body 351 expands due to the thermal expansion of the container main body 351 due to heating at the time of film formation, the movable support portion 392 Since it slides in the axial direction, distortion does not occur in the container body 351.

  Here, when the bottom of the evaporation source case 35 is installed and fixed so that the evaporation source case 35 does not move due to thermal expansion during heating, the expansion of the evaporation source case causes distortion due to the expansion due to the thermal expansion. As a result, the smoothness of the inner bottom surface of the evaporation source case is lost, the evaporation of the thin film material becomes uneven in the plane, and the film thickness of the thin film to be formed varies.

  On the other hand, in the present embodiment, since the evaporation source case 35 is supported by the water cooling plate 31 by the fixed support portion 391 and the movable support portion 392, even if the container body 351 expands due to thermal expansion, Since the evaporation source case 35 is configured to be movable in the X-axis direction by the movable support portion 392, no distortion occurs in the evaporation source case 35. Therefore, it becomes possible to form a thin film of in-plane uniform film thickness.

  In the present embodiment, the movable support portion 392 is installed and fixed to the evaporation source case 35, and the movable support portion 392 is configured to be movable on the inner bottom surface portion of the rectangular water cooling plate 31. It is not limited to. For example, the movable support portion 392 may be installed and fixed to the bottom surface portion 313 of the water cooling plate 31 without being installed and fixed to the evaporation source case 35, and the evaporation source case 35 may be supported by the movable support portion 392. In this case, even if the container main body 351 is expanded due to thermal expansion, the expansion of the container main body 351 is not impeded by the rotation of the movable support portion 392, and distortion is not generated in the evaporation source case 35. A thin film of film thickness can be formed.

  As described above, of the radiation heat from the evaporation source case 35 heated by the heater 34 and the heater 34, radiation heat that can not be shielded by the water cooling plate 31 (first heat shielding plate) and the reflector (third heat shielding plate) 32 Can be reduced by providing the follow-up reflector 33.

The difference in the effect by the presence or absence of the follow-up reflector 33 is demonstrated using FIG.5 and FIG.7.
5 and 7 correspond to partial enlarged views in the vicinity of the nozzle 37 surrounded by the dotted line A in FIG.
FIG. 5 is a partial view of the evaporation source 3 according to the present embodiment in which the follow-up reflector 33 is provided. FIG. 5 is a partially enlarged top view showing a state before and after heating near the nozzle of the evaporation source 3 and a sectional view corresponding thereto.

  7A and 7B are partial views of the evaporation source 203 according to the comparative example in which the follow-up reflector 33 is not provided. FIG. 7A is a partially enlarged top view showing a state before and after heating near the nozzle, and a sectional view corresponding thereto. FIG. 7B shows a state of radiant heat B emitted from the evaporation source at the time of heating. In FIG. 7, the same components as those of the evaporation source 3 according to this embodiment are denoted by the same reference numerals.

  As shown in FIG. 7A, before heating before film formation, the nozzles 375 and 376 are positioned on the left of the inside of the substantially elliptical first openings 3115 and 3116, respectively. On the other hand, when the film formation is heated, the container body 351 thermally expands and elongates in the longitudinal direction, and when the positions of the nozzles 375 and 376 change, the central portions of the first openings 3115 and 3116 respectively The nozzles 375 and 376 are respectively located at

  As shown in FIG. 7B, the radiant heat B from the evaporation source case 35 heated by the heater 34 and the heater 34 is provided in the first opening 311 and the reflector 32 provided in the top surface portion 310 of the water cooling plate 31. The radiation is emitted out of the evaporation source 203 through the third opening 324. The radiant heat B radiated to the outside of the evaporation source 203 reaches the glass substrate 9 and heats the glass substrate 9.

  When the glass substrate 9 is heated and the substrate temperature rises, the vaporized material of the thin film material reaching the glass substrate 9 moves around the glass substrate 9 and does not adhere properly, and re-evaporation is performed to perform film formation properly. Absent.

  In addition, in the case of forming a thin film on a film formation target through a metal mask, the metal mask is expanded by radiant heat, and positional deviation of a film formation pattern occurs. In particular, when forming a thin film of a high definition pattern, the positional deviation of the film forming pattern is large in display characteristics when it is used as a display device when, for example, the glass substrate 9 is a substrate constituting the display device. It will affect.

  On the other hand, in the present embodiment, as shown in FIG. 5, of the radiation heat from the evaporation source case 35 heated by the heater 34 and the heater 34 to the glass substrate 9, radiation heat that can not be shielded by the water cooling plate 31 and the reflector 32. Can be reduced by the tracking reflectors 33 provided corresponding to the first opening 311 and the third opening 324.

  The follow-up reflector 33 can change its position following the change of the position of the nozzle 37 due to the heating during the film formation. Thus, even if the evaporation device 35 expands due to heating at the time of film formation and the position of the nozzle 37 changes, when the water cooling plate 31, the reflector 32 and the tracking reflector 33 are projected onto the top surface 352, The third opening area is configured to be positioned within the projection area of the outline of the follow-up reflector 33, so that the follow-up reflector 33 can reduce the radiation heat as in the case where no thermal expansion occurs.

  Further, even if the evaporation source case 35 is expanded by heating and the positional displacement amount is different for each nozzle 37 and the position of the nozzle 37 is changed, the following reflectors 33 are separately provided for each nozzle 37 separately. Therefore, the movement of the nozzle 37 is not hindered.

  Thus, by providing the follow-up reflector 33, it is possible to shield or reduce the radiant heat from the evaporation source case 35 heated by the heater 34 and the heater 34 toward the glass substrate 9. As a result, the heating of the glass substrate 9 is suppressed, the vaporized substance of the thin film material 36 can be deposited on the glass substrate 9, and film formation can be performed efficiently. Further, in the case where a thin film pattern is formed on the glass substrate 9 using a metal mask, expansion of the metal mask due to radiant heat can be suppressed, and therefore, highly accurate pattern film formation becomes possible.

  Here, the nozzle 37 releases the vapor (vaporization substance) of the thin film material. When the nozzle 37 is cooled and the vapor of the thin film material passing through the nozzle 37 is cooled and liquefied in the nozzle 37, the nozzle is clogged and a desired thin film can not be obtained. Therefore, in the case where the follow-up reflector 33 having a heat shielding function to follow the movement of the nozzle 37 is fixed to the nozzle 37, it is desirable that the nozzle 37 be not cooled as much as possible.

  In the present embodiment, in order to reduce the radiation heat from the evaporation source case 35 heated by the heater 34 and the heater 34 toward the glass substrate 9 and to prevent the nozzle 37 from being cooled as much as possible, It is configured to be fixed by point contact. By fixing the point contact and fixing in this manner, the contact area between the nozzle 37 and the follow-up reflector 33 can be reduced, thereby inhibiting the heat conduction from the nozzle 37 to the follow-up reflector 33. Cooling of the nozzle 37 can be suppressed.

  The follow-up reflector 33 is desirably formed of a material having a low emissivity, for example, 0.1 or less. By reducing the emissivity of the follow-up reflector 33, the heat conduction by radiation becomes low, and the heat quantity of the radiation heat reaching the glass substrate 9 can be reduced. Further, in the case where a thin film pattern is formed on the glass substrate 9 using a metal mask, expansion of the metal mask due to radiant heat can be suppressed, and the occurrence of patterning displacement due to metal expansion can be suppressed. The follow-up reflector 33 may be formed of a material having a low emissivity, or may be a follow-up reflector 33 whose surface is coated with a material having a low emissivity.

  Furthermore, it is desirable to form the tracking reflector 33 by a material having a low thermal conductivity, for example, 10 w / m · k or less, and cooling of the nozzle 37 can be further suppressed.

Preferred materials for the follow-up reflector 33 of the present embodiment, which have low thermal conductivity and low emissivity, include tantalum, molybdenum, tungsten, nickel, cobalt, stainless steel, Inconel (registered trademark), nickel including chromium, iron, silicon, etc. Alloys, etc.) can be used. In addition, inorganic substances such as Al ₂ O ₃ (alumina), BN (boron nitride), PBN (pyrolytic Boron Nitride, boron nitride manufactured by low pressure thermal decomposition CVD (Chemical Vapor deposition)), SiO ₂ (silicon dioxide), inorganic A fiber-based heat insulating material can be used. In this embodiment, PBN with an emissivity of 0.4 or Inconel (registered trademark) with an emissivity of 0.15 was used. Also, in order to lower the emissivity, the surface roughness of the surface of the follow-up reflector 33 may be reduced to a mirror surface.

  As described above, in the present embodiment, by providing the follow-up reflector 33, the amount of heat of radiant heat can be reduced compared to the case where the follow-up reflector 33 is not provided. Therefore, the radiant heat radiated from the evaporation source 3 can be reduced.

  Further, the follow-up reflector 33 is provided individually for each nozzle 37, and the follow-up reflector 33 follows the change in the position of the nozzle 37. Therefore, the evaporation source case 35 expands during film formation, and the positional deviation amount of each nozzle 37 differs. Even if the position changes, the heat quantity of radiant heat can be reduced by the follow-up reflector 33 as it was before thermal expansion.

Second Embodiment
In the above-described embodiment, the follow-up reflector 33 is fixed to the nozzle 37 by point contact, and the contact area between the follow-up reflector 33 and the nozzle 37 is reduced to suppress the cooling of the nozzle 37. For example, a ring-shaped gap member having a low thermal conductivity may be provided between the follow-up reflector 33 and the nozzle 37 to suppress the cooling of the nozzle 37.

  FIG. 6 is a partially enlarged view in the vicinity of the nozzle of the evaporation source 103 according to the second embodiment. FIG. 6A is a partially enlarged perspective view of the evaporation source 103 in the vicinity of the nozzle of the evaporation source 103 as viewed obliquely from above. FIG. 6B is a partially enlarged cross-sectional view of the evaporation source 103. Hereinafter, the same components as those of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The first embodiment and the second embodiment are different in that the shape of the opening of the follow-up reflector is different, and in the second embodiment, a gap member is provided.

  As shown in FIG. 6B, in the evaporation source 103, the second heat is generated between the top surface portion 310 of the water-cooling plate 31 and the reflector 32 along the Z-axis direction, separately from the top surface portion 310 and the reflector 32. A follow-up reflector 1033 as a shielding plate is provided. Further, a ring-shaped gap member 1038 is provided between the tracking reflector 1033 and the nozzle 37. Also in the second embodiment, the tracking reflectors 1033 are individually disposed for each nozzle 37 as in the first embodiment.

  The follow-up reflector 1033 has a rectangular outer shape as the follow-up reflector 33 in the first embodiment. The follow-up reflector 1033 has a second opening 1330 substantially at the center thereof. The second opening 1330 has a substantially circular shape on the XY plane. When the nozzle 37, the tracking reflector 1033, and the ring-shaped gap member 1038 are projected on the XY plane, the outer shape of the nozzle 37 is located within the projection area of the second opening 1330, and the outer shape of the nozzle 37 and the second The openings 1330 overlap in a concentric manner. Furthermore, in the projection view, a ring-shaped gap member 1038 is positioned so as to fill the gap between the outer shape of the nozzle 37 and the second opening 1330.

  The tracking reflector 1033 is fixed to the nozzle 37 via the gap member 1038. As the follow-up reflector 1033 is fixed to the nozzle 37 in this manner, the follow-up reflector 1033 also changes its position following the change in the position of the nozzle 37. By providing the follow-up reflector 1033, the amount of heat of radiation heat from the evaporation source case 35 heated by the heater 34 and the heater 34 which can not be shielded by the water cooling plate 31 and the reflector 32 can be reduced.

  The follow-up reflector 1033 is desirably formed of a material having a low emissivity, and the same material as the follow-up reflector 33 described in the first embodiment can be used.

  It is desirable to use a material with low thermal conductivity for the gap member 1038, for example, it is preferable to use a material with thermal conductivity of 30 w / m · k or less. As a specific material, alumina, silicon nitride, zirconia or the like can be used.

  By using a material having a low thermal conductivity for the gap member 1038, the cooling of the nozzle 37 by the follow-up reflector 1033 can be suppressed, and the selection range of the material used for the follow-up reflector 1033 can be expanded.

  In addition to the structure shown in the first embodiment for fixing the following reflector 33 to the nozzle 37 by the projection 38, a gap member made of a material having a low thermal conductivity is provided between the projection 38 and the nozzle 37. It may be a structure.

Third Embodiment
In the first embodiment, the follow-up reflector 33 supports the nozzle 37 at three points, is fixed to the nozzle 37, and suppresses the cooling of the nozzle 37 by supporting at the points, but is not limited thereto.

  For example, the size of the second opening provided in the follow-up reflector and the outer shape of the nozzle 37 are substantially the same, and the nozzle 37 penetrates the second opening provided in the follow-up reflector to make the follow-up reflector and the nozzle 37 second The tracking reflector may be fixed to the nozzle 37 by contacting at the side of the opening of the In such a structure, in order to shield the radiant heat and to suppress the cooling of the nozzle 37 by the tracking reflector, the tracking reflector has a low thermal conductivity, for example, 30 w / m · k or less, and the emissivity is further reduced. It is desirable to form using a low material, for example, 0.1 or less, for example, PBN with an emissivity of 0.4 or Inconel (registered trademark) with an emissivity of 0.15 can be used.

(Modification)
In the above-mentioned embodiment, although silver was mentioned as an example and explained as a thin film material, it is not limited to this, but the present invention is applicable also to film-forming of organic films, such as a color filter.
Moreover, in the above-mentioned embodiment, although the one follow-up reflector is provided in the nozzle which has one opening part (vaporization substance discharge port), it is not limited to this. For example, one follow-up reflector may be provided for one nozzle having a plurality of openings (vaporized substance discharge ports) arranged in line. For example, one follow-up reflector can be provided for one nozzle having four openings arranged side by side. Here, the nozzle having a plurality of openings also includes the form of a nozzle group in which a plurality of nozzles 37 having one opening 380, which is the structure shown in the above embodiment, are grouped.

1 ... film forming apparatus 2 ... vacuum chamber (storage unit)
3, 103 ... evaporation source 9 ... glass substrate (target for film formation)
31 ... Water-cooled plate (first heat shield plate)
32 ... reflector (third heat shielding plate)
33, 1033 ... Tracking reflector (second heat shielding plate)
34 ... heater (heating device)
35 ... Evaporation source case (Evaporation source container)
36: Thin film material 37: Nozzle 38: Projection 310: Top surface of water-cooled plate 311: First opening 324: Third opening 351: Container body 352: Top surface 380: Nozzle opening 391: Fixed support Part 392 ... Movable support part

Claims (6)

A container body having a top surface and containing a thin film material, and a plurality of nozzles connected to the container body and projecting from the top surface and disposed in a uniaxial direction and having an opening for discharging a vaporized substance of the thin film material; An evaporation source container,
A heating device for heating the container body;
A plurality of first openings spaced apart from the top surface and having a first opening area larger than the opening of the nozzle through which each of the nozzles provided corresponding to each of the plurality of nozzles penetrates. A first heat shield plate comprising
The nozzle is fixed to each of the plurality of nozzles between the container main body and the first heat shield plate, and is disposed to face the top surface at a distance from the top surface, and has an outer shape larger than the first opening area A second heat shield plate having a second opening through which The evaporation source according to claim 1, wherein
The second heat shield plate is fixed to the nozzle by point contact. The evaporation source according to claim 1 or 2, wherein
The first opening has a shape having a longitudinal direction in the uniaxial direction. The evaporation source according to any one of claims 1 to 3, wherein
From the opening of the nozzle which is disposed between the evaporation source container and the second heat shield plate so as to face the top surface and through which each of the nozzles provided corresponding to each of the plurality of nozzles penetrates An evaporation source further comprising a third heat shield plate comprising a plurality of third openings having a large third opening area. The evaporation source according to any one of claims 1 to 4, wherein
The first heat shield plate has an outer shape that surrounds the evaporation source container having a top surface having the first opening and a bottom surface facing the top surface.
The container body is supported by the bottom portion so as to be movable in one axial direction according to the amount of expansion in the one axial direction of the container body due to thermal expansion of the container body due to heating of the heating device. An accommodating portion capable of accommodating a film formation target;
A container main body having a top surface and containing a thin film material, and an opening which is connected to the container main body, protrudes from the top surface and is uniaxially disposed, and releases the vaporized substance of the thin film material toward the film forming object An evaporation source container provided with a plurality of nozzles having a part, a heating device for heating the container body, and each of the nozzles provided opposite to and spaced from the top surface and corresponding to each of the plurality of nozzles Between the container body and the first heat shield plate, a first heat shield plate comprising a plurality of first openings having a first opening area larger than the opening of the nozzle through which A second heat shield fixed to each of the plurality of nozzles and disposed opposite to the top surface and having an outer shape larger than the first opening area and having a second opening through which the nozzle passes The film-forming apparatus equipped with an evaporation source provided with a board.

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