JP6017796B2 - Electron beam evaporation system - Google Patents

Description

  The present invention relates to an electron beam evaporation apparatus that irradiates a material in a crucible with an electron beam to heat and evaporate the material.

  A vapor deposition apparatus using an electron beam evaporates electrons accelerated at a predetermined voltage by vertically irradiating and heating the material in a crucible disposed in the vacuum vessel from above, and the evaporated material is evaporated into the vacuum vessel. The thin film is formed by adhering to the surface of the substrate disposed inside.

  Conventionally, the evaporation unit 1 constituting the vapor deposition apparatus has components such as an electron gun 2, a deflecting magnet 3, a pole piece 4, and a crucible 5 installed horizontally as shown in FIG. Material 6 was evaporated upwards. On the other hand, the board | substrate 7 arrange | positioned above the evaporation part 1 was hold | maintained in the horizontal direction in the state which orient | assigned the surface downward. Hereinafter, the state where the surface is directed downward is referred to as a face-down state. In addition, 6a in FIG. 6 shows the evaporation material evaporated from the crucible 5.

  This electron beam vapor deposition apparatus is used for various purposes because it can form a film at a high speed on many kinds of materials.

  By the way, in recent years, the need for higher-speed film formation has increased, and in electron beam evaporation, as with resistance heating evaporation, there is a need for proximity evaporation in which the distance (T / S) between the substrate and the crucible is shortened. It was.

  However, in the case of electron beam evaporation, if the crucible is brought close to the substrate in order to increase the film forming speed, the film forming portion is easily damaged by the electron beam or electrons scattered from the electron beam. When the backscattered electron shielding magnet 8 is installed between the substrate 7 and the crucible 5 so that scattered electrons do not reach the film forming section (see FIG. 6), the magnet 8 causes the electron beam to enter the crucible 5. There is a problem in that it is difficult to accurately guide the electron beam to the crucible by interfering with the guiding deflection magnet 3.

JP-A-7-211641

  The problem to be solved by the present invention is that, in the case of electron beam evaporation, when the substrate is brought close to the crucible, the film forming part is easily damaged by the electron beam or electrons scattered from the electron beam. Further, when a reflection electron shielding magnet is installed between the substrate and the crucible, it is difficult to accurately guide the electron beam into the crucible.

The electron beam evaporation apparatus of the present invention is
Even if the crucible is brought close to the substrate, it is difficult for the film forming part to be damaged, and even if a reflection electron shielding magnet is installed between the substrate and the crucible, this magnet guides the electron beam into the crucible. To avoid bending the electron beam by interfering with
A horizontally disposed crucible below the substrate, the incident accelerated electrons emitted from the electron gun disposed below of the crucible and the deflection magnet guided in the crucible, the crucible him guide to the deflection magnet Damage to the substrate due to reflected electrons by forming a magnetic field in a position parallel to the substrate between the substrate and the crucible , and a pole piece for controlling the orbit of the electrons in the vicinity of the crucible including the reflected electron orbit generated by the electron beam has a magnet for forming a reflection electron shielding magnetic field for preventing, by electrons led to the crucible is evaporated by heating the material charged into the crucible, a thin film is deposited on the surface of the substrate In the electron beam evaporation apparatus to be formed,
An electron gun for accelerating electrons to be irradiated to the material of the crucible at a predetermined voltage even without low, the deflection magnet for guiding the electron beams emitted from the electron gun into the crucible, the deflection magnet from the substrate as away, oblique arrangement with respect to the crucible of the horizontal state, and the most important feature that has been configured to irradiate an electron in the material in the crucible obliquely from above.

Electron beam vapor deposition apparatus of the present invention, the deflection magnet and electron gun, as the deflection magnet is separated from the substrate, since the inclined arrangement with respect to the crucible in the horizontal state, problems proximity deposition is resolved, Proximity deposition is possible.

  According to the present invention, close deposition is possible, so that it is possible to meet the need for higher-speed film formation. At that time, if the substrate wound on the winding roll is moved by being wound on the winding roll via the roll, film formation at a higher speed becomes possible.

It is the figure which showed schematic structure of the electron beam vapor deposition apparatus of 1st this invention. It is the figure which showed the example schematic structure of the electron beam vapor deposition apparatus of 2nd this invention. It is the figure which showed schematic structure of the electron beam vapor deposition apparatus of 3rd this invention. It is the figure which showed schematic structure of the electron beam vapor deposition apparatus of 4th this invention. It is a figure explaining the installation aspect of the several magnet installed in the grid | lattice form which forms the magnetic field which shields the reflected electron after irradiating the material in a crucible, and an orbit. It is the figure which showed schematic structure of the conventional electron beam vapor deposition apparatus.

  In the present invention, even if the crucible is brought close to the substrate, the film forming portion is hardly damaged, and even when a backscattered electron shielding magnet is installed between the substrate and the crucible, the magnet places the electron beam in the crucible. It solves the problem of preventing the bending of the electron beam by interfering with the guiding deflection magnet.

Then, the object, even without less deflection magnet for guiding the electron gun and the electron beam into the crucible, as the deflection magnet is separated from the substrate (reflection electron shield magnet), tilted with respect to the crucible in the horizontal state This was realized by irradiating the material in the crucible with electrons from diagonally above.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings.
The electron beam vapor deposition apparatus of the present invention has a configuration as shown in FIG. 1 or FIG. 2, for example, when a molten material is used.

  In FIGS. 1 and 2, reference numeral 11 denotes an evaporation portion for the material 12 disposed below the inside of the vacuum vessel. The evaporation section 11 controls an electron gun 13 as an electron beam source, a crucible 14 in which the material 12 that is heated and evaporated by collision of electrons emitted from the electron gun 13 is loaded, and an electron trajectory in the vicinity of the crucible 14 ( For example, the pole piece 15 having a magnet for controlling the scattering direction of the reflected electrons generated by the incidence of the electron beam on the crucible 14 and the path of the electron beam emitted from the electron gun 13 are bent so that the ground potential And a deflection magnet 16 for guiding the crucible 14 into the crucible 14.

In the present invention, for guiding the crucible 14 by emitting at least an electron, the electron gun 13, the deflection magnet 16, as the deflection magnet 16 is separated from the substrate 17, inclined with respect to the crucible 14 in the horizontal state It is characteristic that it is arranged so that electrons are irradiated to the material 12 in the crucible 14 from obliquely above.

  In this case, as shown in FIG. 1 and FIG. 2, if the crucible 14 is disposed above the pole piece 15, the amount of evaporation material 12a attached to the pole piece 15 can be reduced, and film formation is performed. Yield is improved.

  In the present invention having such a configuration, even if the crucible 14 is brought close to the substrate 17 in order to increase the speed required for film formation, the relative distance between the electron beam trajectory and the substrate 17 becomes larger than the conventional one. Damage to the film forming portion is less likely to occur due to the electron beam or electrons scattered from the electron beam.

  Further, as shown in FIG. 1 and FIG. 2, even if a backscattered electron shielding magnet 18 is installed between the substrate 17 and the crucible 14, the magnet 18 causes the electron beam to enter the crucible 14 for the same reason. There is no interference with the deflecting magnet 16 to guide and the electron beam is not bent.

  The backscattered electron shielding magnet 18 forms a magnetic field at a position parallel to the substrate 17 and prevents damage to the substrate 17 by reflected electrons or the like, and does not interfere with film formation at a position close to the substrate 17. Installed in position. When a plurality of the backscattered electron shielding magnets 18 are installed on the substrate 17 so as to form a lattice with a predetermined interval, the crucible 14 is further arranged closer to the substrate 17 (backscattered electron shielding magnet 18) side. it can.

  If the plurality of backscattered electron shielding magnets 18 installed in a lattice shape are placed close to the substrate 17 and substantially parallel to the substrate 17 (along the curved surface of the cooling roll 24 in the example of FIG. 3), the shadows are reduced. This is desirable because the deposition rate is improved.

  Further, in order to form a magnetic field that can prevent the reflected electrons after irradiation of the material 12 in the crucible 14 and the electrons deviating from the trajectory from entering the film forming range, a plurality of magnets 18 arranged in a lattice shape are used. The magnetic flux density between them is 6 mT or more and 10 mT or less. However, as long as such a magnetic field can be formed, a permanent magnet or an electromagnet may be used. The material may be any of ferrite, samarium cobalt, neodymium and the like.

  Like the electron beam evaporation apparatus of the present invention having the above-described configuration, a magnetic field is formed to shield the reflected electrons and the electrons deviating from the orbit after being irradiated on the material 12 in the crucible 14 by a plurality of magnets 18 arranged in a lattice shape. In this case, as shown in FIG. 5, even when the film forming range is wide (for example, 350 mm), the magnetic field strength of each magnet 18 installed in a lattice shape can be reduced.

By the way, in the electron beam evaporation apparatus, the inclination angle θ1 of the electron gun 13 and the deflecting magnet 16 with respect to the substrate 17 parallel to the horizontal crucible 14 is such that the incident angle α of electrons to the crucible 14 is 30 to 45 °. It is desirable to incline so as to be inside.

  Although the deflection angle of the electron beam from the electron gun 13 to the crucible 14 (the surface of the material 12) is not particularly limited, the electron gun 13 is not affected by the vapor deposition material or dust, and the deflection of the electron beam. The range in which the angle can be controlled is preferably 225 ° to 315 °.

  This is because, when the incident angle α of electrons to the crucible 14 is less than 30 °, the heating action of the material 12 in the crucible 14 is weakened, the evaporation amount is reduced, and the merit of proximity vapor deposition is lost. In addition, when the incident angle α of electrons to the crucible 14 exceeds 45 °, the reflected electron shielding magnet 18 interferes with the deflection magnet 16 that guides the electron beam into the crucible 14.

  On the other hand, for example, as shown in FIG. 2, the substrate 17 may be held with an inclination of 5 to 15 ° in the direction opposite to the inclination of the electron gun 13 and the deflection magnet 16.

  The inclination angle θ2 of the substrate 17 is not limited to the range of 5 to 15 °, but if it is less than 5 °, the effect of high-speed film formation due to the inclination of the substrate 17 cannot be obtained. Since the thickness distribution becomes non-uniform, it is desirable to set the range of 5 to 15 °.

  Thus, when the substrate 17 is tilted in the direction opposite to the tilt of the electron gun 13 and the deflection magnet 16, the distance between the deflection magnet 16 and the backscattered electron shielding magnet 18 becomes larger. Can be brought closer to the substrate 17.

  For example, as shown in FIG. 3, the substrate 17 is wound around the unwinding roll 21, wound around the cooling roll 24 via the idle roll 22 and the tension control roll 23, and then passed through the tension control roll 23 and the idle roll 22. If it winds up to the winding roll 25, film-forming at higher speed will be attained.

  At that time, as shown in FIG. 4, if two electron beam vapor deposition apparatuses shown in FIG. 3 are arranged in a line-symmetrical position with respect to the vertical line lowered from the center of the cooling roll 24, it can be formed at a higher speed. It becomes possible to film.

Incidentally, using the electron beam vapor deposition apparatus of the present invention shown in FIGS. 1 and 2 and the conventional electron beam vapor deposition apparatus shown in FIG. 6 , the vapor deposition rate directly above the crucible was measured under the following conditions. It was 40 nm / second for the apparatus of 1, 80 nm / second for the apparatus of FIG. 2, and 10 nm / second for the apparatus of FIG. 6 .

  Thereby, according to this invention, it turned out that proximity | contact vapor deposition is attained and the film-forming at a further high speed can be performed now.

(Deposition conditions)
・ Acceleration voltage: 2kV
・ Emission current: 300mA
-Beam deflection angle: 270 °
・ Distance between crucible and substrate (T / S): FIG. 1 is 200 mm, FIG. 2 is 150 mm, and FIG. 6 is 400 mm.

  The present invention is not limited to the above examples, and it goes without saying that the embodiments may be changed as appropriate within the scope of the technical idea described in each claim.

  For example, in FIGS. 1 to 4, the crucible 14 is arranged at a position above the pole piece 15, but if the influence of the amount of evaporation material 12 a on the pole piece 15 on the film formation rate does not matter. The crucible 14 may be disposed at a position below the pole piece 15.

  Moreover, the evaporation part 11 (deflection magnet 16) may be arrange | positioned so that it may incline not only to the paper surface right-and-left side like FIG.

DESCRIPTION OF SYMBOLS 11 Evaporating part 12 Material 13 Electron gun 14 Crucible 16 Deflection magnet 17 Substrate 18 Magnet 21 Unwinding roll 24 Cooling roll 25 Winding roll

Claims (4)

A horizontally disposed crucible below the substrate, the incident accelerated electrons emitted from the electron gun disposed below of the crucible and the deflection magnet guided in the crucible, the crucible him guide to the deflection magnet Damage to the substrate due to reflected electrons by forming a magnetic field in a position parallel to the substrate between the substrate and the crucible , and a pole piece for controlling the orbit of the electrons in the vicinity of the crucible including the reflected electron orbit generated by the electron beam has a magnet for forming a reflection electron shielding magnetic field for preventing, by electrons led to the crucible is evaporated by heating the material charged into the crucible, a thin film is deposited on the surface of the substrate In the electron beam evaporation apparatus to be formed,
An electron gun for accelerating electrons to be irradiated to the material of the crucible at a predetermined voltage even without low, the deflection magnet for guiding the electron beams emitted from the electron gun into the crucible, the deflection magnet from the substrate as away, the inclined arranged relative to the crucible in the horizontal state, an electron beam vapor deposition apparatus characterized by being configured so as to irradiate the electrons in the material in the crucible obliquely from above.   2. The electron beam evaporation apparatus according to claim 1, wherein the electron gun and the deflecting magnet are inclined so that an incident angle of an electron beam to the crucible is within a range of 30 to 45 °.   The electron beam deposition apparatus according to claim 1, wherein the substrate is held at an inclination with respect to a material surface in the crucible.   An electron beam evaporation apparatus according to any one of claims 1 to 3, wherein two electron beam evaporation apparatuses are arranged at positions symmetrical with respect to a vertical line dropped from the center of the evaporation range of the substrate.

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