JP3021536B2 - Heating device using hollow cathode discharge - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a heating device using hollow cathode discharge which can be used as, for example, an evaporation source or a heating device for melting.

[Prior Art] As a conventional heating device utilizing hollow cathode discharge, for example, as shown in FIG.
And an anode B to be heated, and a coil S for converging a beam. The cathode A has a cylindrical shape so that gas can be introduced therethrough.
These assemblies are usually installed in a container that can be evacuated, and the anode B and the coil C are water-cooled.

In this conventional apparatus, a hollow cathode discharge is generated by introducing an argon gas from a cathode A and applying a voltage so that an anode B has a positive potential, whereby electrons emitted from the cathode A are converted into an anode. B and heats the anode B. The magnetic field generated by the converging coil C has a function of preventing the beam of the hollow cathode discharge from spatially expanding, stabilizes the discharge, and enables the object to be heated to be efficiently heated. Utilizing this heat generation effect, it is used for an evaporation source and a heating device for melting in vacuum evaporation.

As another conventional example, the one shown in FIGS. 7 and 8 is known. This apparatus has a cylindrical cathode D, an anode E, a coil F for moving a beam, and both sides of the anode E. The yoke G extends along the same and is installed in a container which can be evacuated as in the case of FIG. 6, and the anode E and the coil F are water-cooled.

In this conventional example, as in the case of the conventional example shown in FIG. 6, an argon gas is introduced through a cylindrical cathode D, and a hollow cathode discharge is generated between itself and an anode E. Heated. in this case,
The direction of the magnetic field generated by the beam moving coil F is perpendicular to the beam, and the beam is bent perpendicular to this field as shown. The trajectory of the beam can be changed by changing the current flowing through the beam moving coil F to adjust the magnetic field strength. Can be heated.

[Problems to be Solved by the Invention] In a conventionally known device as shown in FIG. 6, since a beam is converged by a converging coil C, the heating portion on the anode B is limited to one point. Therefore, when used as an evaporation source, there has been a problem that evaporation unevenness occurs in the evaporation material.

When this apparatus is used for melting, there is a problem that a large area cannot be heated unless the cathode is moved mechanically.

On the other hand, in a device having a structure as shown in FIGS. 7 and 8, a magnetic field is generated perpendicular to the beam. Is not possible, so
It is inevitable that the beam expands to some extent, and as a result, there is a problem that efficient heating cannot be achieved.

Therefore, the present invention solves the problems associated with such a conventionally known device, and provides a heating device utilizing hollow cathode discharge which has good heating efficiency and can be easily applied to any heating portion. It is an object.

Means for Solving the Problems In order to achieve the above object, according to the present invention, in a heating apparatus using a hollow cathode discharge provided with a beam focusing coil, a space is provided around an axis of an anode. A beam position control coil, which comprises a plurality of coils arranged in a row and surrounds the vicinity of the anode and generates an inhomogeneous magnetic field having a component parallel to the magnetic field of the beam converging coil, is provided.

[Operation] In the heating device according to the present invention configured as described above, the magnetic field generated by the beam moving coil is a non-uniform magnetic field near the anode forming the object to be heated, and the current supplied to the beam moving coil is Can be adjusted to change the distribution, and thereby the heating position on the anode where the beam hits can be arbitrarily adjusted.

In addition, since the non-uniform magnetic field generated by the beam moving coil has a component parallel to the magnetic field generated by the beam focusing coil, the degree of convergence of the beam and the beam position can be controlled independently. As a result, the degree of freedom of the heating operation is increased, and efficient heating and arbitrary heating positions can be achieved at the same time.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 to 5 in the accompanying drawings.

FIG. 1 schematically shows the configuration of an embodiment in which the present invention is applied to an evaporation source. In the illustrated apparatus, reference numeral 1 denotes a cylindrical cathode, 2 denotes a water-cooled anode (hearth), in which an evaporating substance to be heated is provided. 3 is inserted. Numeral 4 denotes a beam focusing coil, numeral 5 denotes a yoke member which extends in a cross shape across the bottom of the water-cooled anode 2 and extends to the upper side edge of the water-cooled anode 2 as shown in FIG. A beam position control coil mounted on the member 5, the beam position control coil 6 comprising two X-axis coils 7 and two Y-axis coils 8 (only one of them is shown in the drawing). I have.

In operation, the beam generated by the hollow cathode discharge is formed in a direction along the direction of the magnetic field generated by the beam focusing coil 4 (indicated by a dotted arrow in the drawing). In this state, when the two X-axis coils 7 of the beam position control coil 6 are energized, one of the two X-axis coils 7 receives the forward magnetic field component from the beam converging coil 4 and the other X-axis coil 7. Is designed to generate a magnetic field component in the reverse direction at the tip of the coke member 5, so that the direction of the magnetic field near the anode 2 is bent toward the X-axis coil 7 that generates a magnetic field component in the forward direction. The position of the collision of the beam on the anode 2 is also moved along. The beam moving distance can be adjusted by changing the current applied to each X-axis coil 7, and the direction of the magnetic field can be reversed by reversing the polarity of the supplied current to reverse the beam moving direction. Can be. Then, the excitation of the two Y-axis coils 8 of the beam position control coil 6 is similarly controlled to adjust the movement of the beam in the y-axis direction. Therefore, by appropriately controlling the two X-axis coils 7 and the two Y-axis coils 8 of the beam position control coil 6, the collision position of the beam on the anode 2 can be arbitrarily controlled.

FIG. 3 shows another embodiment in which the present invention is implemented as a heating device for melting, in which 11 is a cylindrical cathode,
Reference numeral 12 denotes a water-cooled anode (hearth) into which a melting material 13 to be heated is inserted. 14 is a beam converging coil. In this embodiment, a cylindrical yoke member 15 is provided to surround the periphery of the water-cooled anode 12 as shown in FIG. The mounted beam position control coil 16 includes two X-axis coils 17 and two Y-axis coils 18.
The X-axis coil 17 and the Y-axis coil 18 are mounted on the yoke member 15 at an interval of 90 ° as shown.

Also in this embodiment, the beam is moved to the entire area of the molten material 13 by appropriately exciting the two X-axis coils 17 and the two Y-axis coils 18 of the beam position control coil 16 in the same manner as in the previous embodiment. And heat it.

By the way, in each of the illustrated embodiments, the cathode is disposed immediately above the anode in order to generate a hollow cathode discharge beam, but instead, as shown in FIG.
It is also possible to arrange so that 21 is positioned obliquely above the anode 22 to generate a hollow cathode discharge beam. In FIG. 5, reference numeral 23 denotes an evaporating material mounted on the anode 22, 24 denotes a beam focusing coil, 25 denotes a yoke member, and 26 denotes a yoke member.
Is a beam position control coil mounted on the yoke member 25.

In each embodiment, the coil for controlling the beam position has a configuration in which two coils are provided in the X-axis and Y-axis directions. However, the angular position and the number of each provided coil can be arbitrarily designed as necessary. .

[Effects of the Invention] As described above, according to the present invention, a beam moving coil that generates an inhomogeneous magnetic field having a component parallel to the magnetic field generated by the beam focusing coil in the vicinity of the anode forming the object to be heated By appropriately controlling the excitation of the beam moving coil, the collision position of the beam with respect to the object to be heated can be arbitrarily controlled. As a result, the heating can be efficiently performed from a small area to a relatively large area. And a device useful as an evaporation source or a heating device for melting can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one embodiment of the present invention, FIG. 2 is a schematic plan view of an anode part of the apparatus of FIG. 1, FIG. 3 is a schematic sectional view showing another embodiment of the present invention, 4 is a schematic plan view of an anode part in the apparatus of FIG. 3, FIG. 5 is a schematic sectional view showing a modified embodiment of the present invention, and FIG. 6 is an example of a conventional heating apparatus utilizing hollow cathode discharge. Schematic diagram showing,
7 and 8 are a schematic side view and a sectional view showing an example of another conventional heating device. In the figure, 1: cylindrical cathode 2: anode (hearth) 3: evaporating substance to be heated 4: beam focusing coil 5: yoke member 6: beam position control coil 7: X-axis coil 8: Y-axis coil 11: cylinder Cathode 12: Water-cooled anode (hearth) 13: Melting material to be heated 14: Beam focusing coil 15: Cylindrical yoke member 16: Beam position control coil 17: X-axis coil 18: Y-axis coil

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazuhiro Watanabe 5-9-9 Tokodai, Tsukuba, Ibaraki Pref. Tsukuba Super Materials Laboratory, Japan Vacuum Engineering Co., Ltd. (56) References A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C23C 14/00-14/58 H01J 37/30

Claims (1)

(57) [Claims] 1. A heating apparatus using a hollow cathode discharge provided with a coil for converging a beam, comprising a plurality of coils arranged at intervals around an axis of the anode, and surrounding the periphery of the coil in the vicinity of the anode. A heating device utilizing hollow cathode discharge, wherein a beam position control coil for generating an inhomogeneous magnetic field having a component parallel to the magnetic field generated by the focusing coil is provided.