JPH04210469A - Ion plating device - Google Patents

Abstract

PURPOSE:To control a change in the probability of collision of an electron beam with the vaporized particles, etc., due to the pressure change in a vessel and to uniformize the quality of a film by providing a means for changing the injection angle of the electron beam and changing the traveling distance of the electron beam. CONSTITUTION:A vaporization material 4 in a crucible 3 is irradiated with an electron beam E1 and vaporized. A magnetic field B is generated between the crucible 3 and a substrate 7, and an electron beam E2 is spirally emitted from an electron gun 9 toward an electrode 14. In this process, a gaseous reactant collides with the vaporized particles and is ionized to produce plasma P, and a positive ion collides with the substrate 7 to form a compd. thin film on the surface. The pressure in the vessel 1 is detected by a vacuum gage 19, the injection angle of the beam E2 is changed in accordance with the pressure, and the traveling distance of the electron is changed. The change in the probability of collison of the electron with vaporized particles, etc., due to the pressure change in the vessel 1 is kept constant.

Description

[Detailed description of the invention]

[00011

[Field of Industrial Application] The present invention relates to an ion plating apparatus that ionizes an evaporated substance and causes it to collide with a substrate to form a film. [0002] [0002] In such an ion plating apparatus, in order to improve film quality and promote ionization of reaction gas, a second hollow cathode gun is provided in addition to a first hollow cathode gun for evaporating evaporated substances. An ion plating apparatus has been proposed that incorporates a gun and uses an electron beam from a second hollow cathode gun to ionize reaction gas and evaporated particles into plasma, and also ionizes evaporated particles. [0003] However, in such a device, an electrode is provided opposite to the hollow cathode gun, and the electron beam from the hollow cathode gun is made to travel straight in a direction perpendicular to the traveling direction of the evaporated particles, so there is no reaction. It is not possible to convert gas, etc. into plasma efficiently. [0004] Recently, in order to efficiently convert reactive gases, etc. into plasma, a magnetic field is formed in the container to cause the electron beam to travel spirally toward the substrate, thereby increasing the interaction between the electron beam and the reactive gas. A device has been proposed that increases the number of collisions as much as possible. [0005]

[Problems to be Solved by the Invention] If the electron beam is made to travel in a spiral pattern in this way, plasma can be generated efficiently and film formation can be accelerated, but on the other hand, it is affected by the pressure inside the container. It is easy to absorb and the film quality deteriorates. In other words, the number of collisions (probability of collision) between the electron beam and the evaporated particles or reaction gas varies greatly depending on whether the pressure inside the container is high or low, so the plasma generation rate changes and the film quality remains constant. It becomes impossible to do so, and reproducibility decreases. [0006] Therefore, in view of this point, an object of the present invention is to provide an ion plating apparatus that can suppress changes in film quality due to pressure changes and can form a thin film with good reproducibility. It is something. [0007]

[Means for Solving the Problems] In order to achieve the above object, the ion plating apparatus of the present invention includes means for heating and evaporating an evaporation substance contained in a crucible, and a means disposed opposite to the crucible. a substrate held by the holder; an electron beam generating means for emitting an electron beam toward a space between the substrate and the crucible; and directing the electron beam from the electron beam generating means toward the substrate. a magnetic field generating means for causing the electron beam to advance while drawing a spiral trajectory, and a means for changing the emission angle of the electron beam emitted from the electron beam generating means between the crucible and the substrate. be. [00081 Hereinafter, embodiments of the present invention will be explained in detail based on the drawings. [0009]

[Example] FIG. 1 is a sectional view of a schematic configuration diagram showing an example of an ion plating apparatus according to the present invention, and FIG.
It is an A sectional view. [00101 In the figure, 1 is a container, and the inside thereof is connected to a vacuum pump (not shown) through an exhaust port 2 to maintain a vacuum. 3 is a crucible containing evaporated substance 4, 5 is evaporated substance 4
a hollow cathode gun for heating and evaporating the crucible; 6 is a holder for holding the substrate 7 placed opposite the crucible 3;
The holder is supported within the container 1 via an electrically insulating material (not shown), and a negative bias voltage is applied to this holder from a bias power supply 8. [001119 is an electron gun for generating an electron beam, and this electron gun is fixed to the outer wall of the container 1 so as to be located between the crucible 3 and the substrate 7. Reference numeral 10 denotes an electrostatic deflection system for deflecting the electron beam from the electron gun in the vertical and horizontal directions (horizontal direction), which includes a pair of X and Y direction deflection plates 11 and 12 arranged orthogonally to each other. It is configured. Reference numeral 13 denotes a deflection power supply for applying electrostatic voltages to the X and Y direction deflection plates, and 14 indicates a beam-shaped anode electrode arranged near the outer periphery of the holder 6, which is maintained at a positive voltage by a power supply 15. ing. [0012] Numerals 16 and 17 are electromagnetic coils for forming a magnetic field perpendicular to the space between the crucible 1 and the substrate 7 in the container 1, and are fixed to the outer wall of the container 1. [0013118 is an introduction pipe for introducing a reaction gas into the container 1, 19 is a vacuum gauge for measuring the pressure inside the container 1, and 20 is arranged to surround the outer periphery of the electrostatic deflection system 10. It is a shield tube made of aluminum. [0014] In this configuration, first, the inside of the container 1 is heated to an arbitrary pressure (for example, 10-5 to 1O-7
After exhausting the gas to a pressure of about 10.5 Torr (approx. Torr), a reactive gas such as oxygen or nitrogen is introduced from the introduction pipe 18. And electromagnetic coil 1
A vertical magnetic field B is formed in the container 1 by applying the same current to each of the hollow cathode guns 5 and 6.17.
The electron beam E1 is irradiated onto the evaporated substance 4 in the crucible 3, and the substance 4 is heated and evaporated as shown by arrow C. In this state, the electron beam E2 from the electron gun 9 is emitted into the container (2), and a pair of X
When the electron beam is deflected along the inner wall of the container 1 by applying a voltage to the direction deflection plate 11, the electron beam is deflected by the perpendicular magnetic field B and rotates above the crucible 3 as shown in FIG. At the same time, if a voltage is applied to the other pair of Y-direction deflection plates 12 to deflect the electron beam E2 so as to emit it slightly upward, the electron beam will spiral as shown by the solid line in FIG. Head to 14th. As this electron beam ascends in a spiral, it repeatedly collides with evaporated particles and reaction gases from the crucible 3, dissociating, exciting, or ionizing them, resulting in a high-density plasma
to occur. At this time, since a negative bias voltage is applied to the holder 6, positive ions in the generated plasma are accelerated and collide with the substrate 7, so that a thin compound film formed by a chemical reaction is formed on the substrate surface. Ru. Here, if a positive voltage is applied to the anode electrode 14 as shown in this embodiment, the electron beam E2 whose energy has been attenuated by collision with evaporated particles and reaction gas can be attracted to this anode electrode. In other words, since the electron beam can be brought close to the substrate 7, it is possible to generate plasma P not only in the intermediate area between the crucible 3 and the substrate 1, but also in the vicinity of the substrate, which is highly efficient. Film formation can be performed. [0015] By the way, if the pressure inside the container 1 changes due to changes in the amount of reaction gas introduced from the introduction pipe 18 or the amount of gas released from the wall, collisions between the electron beam E2 and the evaporated particles and the reaction gas occur. The probability changes, making it impossible to keep the film quality constant and causing a decrease in reproducibility. Therefore, when it is confirmed by the pressure gauge 19 that the pressure inside the container 1 has increased, the deflection power source 13 is operated to cause the Y-direction deflection plate 12 to
The amount of upward deflection of the electron beam E2 is increased, that is, the deflection angle of the electron beam emitted into the container 1 is increased toward the substrate 7 side from the solid line in FIG. 1, and the distance along the spiral trajectory of the electron beam is shortened. Conversely, when it is confirmed that the pressure inside the container has decreased, the deflection angle of the electron beam is made smaller toward the crucible 3 side than the solid line in FIG. 1, and the distance of the helical trajectory of the electron beam is increased. [00163 In this way, by changing the deflection angle of the electron beam toward the substrate as the pressure inside the container 1 changes, the spiral traveling distance of the electron beam can be changed. The probability of collision between the evaporated particles and the reactant gas is kept constant, and changes in film quality due to pressure changes can be prevented, and thin films with good reproducibility can be formed. [00171 The above description is an example of the present invention, and many modifications can be made in implementing the present invention. For example, in the above embodiment, it was described that the upward deflection angle of the electron beam E2 was controlled by checking the pressure inside the container 1 with a vacuum gauge.
The present invention is not limited to this, and the configuration may be such that the pressure inside the container 1 is constantly detected and the deflection power source 13 is automatically controlled. That is, as shown in FIG. 3, a control circuit 21 is provided to which the output signal from the vacuum gauge 19 is introduced, and this control circuit is stored with appropriate deflection angles for each pressure inside the container, which have been determined in advance through experiments or the like. The deflection angle of the electron beam will be automatically set according to the pressure change inside the container.
Collision between the electron beam and the evaporated particles or reactant gas can always occur at a constant rate. [0018] Furthermore, in the above description, the electron beam is directed upward (on the substrate 7 side) in order to spirally deflect the l beam E2.
Although it was deflected toward the above, it may also be deflected downward (toward the crucible 3 side). [0019]Also, in the above embodiment, the case was described in which the same current was supplied to each of the deflection coils 16 and 17 in order to form a vertical magnetic field B in the container, but it is possible to change the amount of current flowing through each coil. This allows the shape of the plasma P to be changed. For example, if the current flowing in the lower deflection coil is made larger than that in the upper deflection coil, the magnetic field on the substrate side becomes weaker, and as a result, the lines of magnetic force spread toward the outside of the container at the substrate portion. As a result, the plasma P is pushed upward by the magnetic field below, and the plasma is distributed in a spread state near the substrate. Even if a large substrate is used, the plasma can be distributed over the entire surface of the substrate, making it possible to efficiently form thin films. It becomes possible to form. In other words, the current flowing through each deflection coil can be adjusted depending on the size of the substrate. Therefore, the upper deflection coil may not be used. [00201 Furthermore, in the above embodiment, the anode electrode 1
Although a positive voltage was applied to 4, it may be set to ground potential. In this case, the container itself may be used as an anode electrode without using this anode electrode. [0021] Furthermore, in the above embodiment, the electron beam E2
Although an electrostatic deflection system is used as the deflection means, an electromagnetic deflection system may also be used. [0022]Furthermore, in the above embodiment, the deflection angle of the electron beam E2 in the horizontal direction and in the direction of the crucible and the substrate was adjusted using the deflection means, but the electron gun was kept in vacuum with respect to the side wall of the container. The electron gun may be mounted so as to be rotatable up and down and left and right, and the direction of introduction of the electron beam may be adjusted by moving the electron gun itself manually or automatically by electrical means. [0023] Further, in the above embodiment, the evaporation material was heated and evaporated using a hollow cathode gun, but other known heating means such as an electron beam may be used. [0024]

Effects of the Invention According to the present invention described in detail above, when ionizing evaporated particles and reaction gas while making the electron beam travel in a spiral pattern, the emission angle of the electron beam emitted between the crucible and the substrate can be adjusted. Since the traveling distance of the electron beam can be changed arbitrarily, the change in the probability of collision between the electron beam and the evaporated particles or the reactant gas due to changes in the pressure inside the container can be kept constant. As a result, it is possible to form a thin film with constant film quality regardless of pressure changes, and it is also possible to provide an ion plating apparatus with good reproducibility.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a schematic configuration diagram showing an example of an ion plating apparatus according to the present invention.

FIG. 2 is a sectional view taken along line AA in FIG. 1.

FIG. 3 is a cross-sectional view of a schematic configuration diagram showing another example of the ion fluting device according to the present invention.

[Explanation of symbols]

1: Container 2: Exhaust port 3: Ru°tsubo 4: Evaporated substance 5: Hollow cathode gasi 6: Holder 72 board 8: Bias power supply 9; Electron gun 10: Electrostatic deflection system 11.12: X, Y direction deflection plate 13: Deflection power supply 13 Near Node Electrode 15: Bias power supply 16.17: Deflection coil 18:Introduction pipe 19: Vacuum gauge 20: Shield tube 21: Control circuit

Claims (1)

[Claims] 1. A means for heating and evaporating an evaporative substance contained in a crucible, a substrate placed to face the crucible and held in a holder, and a space between the substrate and the crucible. an electron beam generating means for emitting an electron beam toward the substrate, and a magnetic field generating means for causing the electron beam from the electron beam generating means to travel toward the substrate while drawing a spiral trajectory, An ion plating apparatus characterized by comprising means for changing the emission angle of an electron beam emitted from a generation means between a crucible and a substrate.