JPH05106031A - Thin film forming equipment - Google Patents

Abstract

PURPOSE:To provide thin film forming equipment capable of performing ion-species- selected film production and also capable of forming a thin film having high adhesive strength even on, e.g. a large-area substrate without heat resistance. CONSTITUTION:The equipment has a vacuum tank 11 where active gas and/or inert gas is introduced, a material supply source 1 arranged in the central part of the vacuum tank and uniformly emitting a material toward a substrate 10, a counter electrode 4 cylindrically disposed along the internal wall of the vacuum tank and holding the substrate, a grid 3 cylindrically arranged between the material supply source and the counter electrode, a filament 2 cylindrically disposed between the material supply source and the grid, a means 9 of providing positive potential to the grid with respect to the filament, means 6a-6d of generating magnetic field in the direction orthogonal to the direction of the electric field between the grid and the counter electrode, a means of controlling the intensity of the magnetic field, a means of providing positive potential to the material supply source with respect to the filament and heating the material supply source by means of electron bombardment, means 8, 9 of electric power source, and an electrically conducting means electrically connecting the inside of the vacuum tank to the means of electric power source.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus, and particularly to strong reactivity, which is an advantage of the CVD method, and film formation in a high vacuum, which is an advantage of the PVD method. A thin film forming apparatus that enables the selective formation of ionic species on the surface of a substrate, which is important for the formation of amorphous silicon or diamond-like carbon film, in a large area. Regarding

[0002]

2. Description of the Related Art As means for forming a thin film on a thin film forming substrate (hereinafter referred to as a substrate), there have been conventionally used a CVD method and a PV method.
Various methods have been proposed based on the D method and the like, and the methods are extremely diverse. However, in the conventional thin film forming apparatus, the adhesion of the formed film to the substrate is weak, or it is difficult to form the thin film on the substrate having no heat resistance. There is a problem that it is difficult to form the thin film. Therefore, the applicant first
As a thin film forming apparatus, a grid is arranged between an evaporation source and a counter electrode that holds a substrate so as to face the evaporation source, a filament for generating thermoelectrons is arranged between the grid and the evaporation source, and the grid is formed. An apparatus for forming a thin film with a positive potential applied to the filament has been proposed (see Japanese Patent Publication No. 1-53351). In this device, the evaporation material evaporated from the evaporation source is first ionized by thermoelectrons from the filament. When the ionized vaporized substance passes through the grid in this way, it is accelerated by the action of the electric field from the grid toward the counter electrode and collides with the substrate to form a film with good adhesion.

[0003]

However, even in the case of the above-mentioned thin film forming apparatus, it is difficult to form a thin film based on the selection of ion species, and it is particularly effective when forming a film of amorphous silicon or diamond-like carbon. The selection of the ion species incident on a different substrate was not dealt with, and promotion of sp ³ bonding, which is important for the physical properties of the film, could not be achieved. The present invention has been made in view of the above circumstances, and it is possible to form a film by ion species selection, form a thin film having extremely strong adhesion to a substrate, and a large area plastic without heat resistance, etc. It is an object of the present invention to provide a novel thin film forming apparatus that can be used as a substrate.

[0004]

In order to achieve the above object, a thin film forming apparatus according to a first aspect of the present invention comprises a vacuum chamber into which an active gas or an inert gas or a mixed gas of both of them is introduced, and the above vacuum. Inside the chamber, a material supply source that is placed at the center of the vacuum chamber and has a radiation nozzle added to uniformly radiate the thin film forming gas material substance to the substrate, or vaporize the thin film forming solid material substance and direct it to the substrate Uniformly radiating material supply source, a plurality of flat plate counter electrodes holding a plurality of thin film forming substrates arranged in a cylindrical shape along the inner wall of the vacuum chamber, or a single cylindrical counter electrode, and the above material supply A grid capable of passing a cylindrically-arranged material substance between a source and the counter electrode; a filament for thermoelectron generation cylindrically arranged between the material supply source and the grid; Grit A positive potential with respect to the filament, a magnetic field generating means (a plurality of electromagnets or permanent magnets) for generating a magnetic field in a direction orthogonal to the electric field direction generated between the grid and the counter electrode, Means for controlling the strength of the magnetic field, means for heating the material supply source by electron bombardment to bring the material supply source to a positive potential with respect to the filament, and for realizing a predetermined electrical state in the vacuum chamber Power source means, having a conductive means for electrically connecting the inside of the vacuum chamber and the power source means, radially emits a material substance from the material supply source,
By controlling the intensity of the electric field in the radial direction and the intensity of the magnetic field orthogonal to the electric field, the ionic valence and the mass can be selected to enable selective film formation of ionic species.

According to a second aspect of the present invention, in the thin film forming apparatus, a cylindrical second grid is installed between the grid and the counter electrode, and an electric field generated between the grid and the second grid is applied. It is characterized by having a method of accelerating the ion species to the substrate surface between the second grid and the counter electrode by applying a magnetic field so as to be orthogonal to each other and enabling the selection of the ion species. Further, in the thin film forming apparatus according to claim 3, in the thin film forming apparatus, a hydrogen atom gun using a hot filament is installed in the center of the vacuum chamber in order to supply a high concentration of hydrogen atoms to the thin film forming substrate. Characterize. A thin film forming apparatus according to a fourth aspect of the present invention is characterized in that, in the thin film forming apparatus, a method is provided in which a nozzle is installed at a radiation port of a hydrogen atom gun to accelerate the nozzle.

[0006]

The structure and operation of the thin film forming apparatus of the present invention will be described in detail below. The thin film forming apparatus according to claim 1 is, as described above, a uniform radiation type material gas supply source or evaporation source with a multi-nozzle, and a single type or polygonal type substrate holding counter electrode arranged in a cylindrical shape ( Hereinafter, referred to as a substrate electrode), a cylindrical acceleration grid arranged between the material supply source and the substrate electrode, and a cylindrical acceleration grid arranged between the grid and the material gas supply source for thermionic generation. It has a filament, a power supply means for making the grid a positive potential with respect to the filament, a conducting means, and a magnetic field generating means for generating a magnetic field orthogonal to the electric field applied between the acceleration grid and the substrate electrode.

The vacuum chamber can introduce an active gas, an inert gas, or a mixed gas of an active gas and an inert gas into its internal space. The material gas supply source, the substrate electrode, and The grid and filament are placed in a vacuum chamber. The permanent magnet or electromagnet for generating a magnetic field may be installed inside or outside the vacuum chamber, but in the case of being externally attached, it is necessary to select a reactor wall material that does not block the magnetic field. The grid allows passage of the substance dissociated in the filament part, is interposed between the material gas supply part and the substrate electrode, and is made to have a positive potential with respect to the filament by the power supply means. Therefore, the electric field generated is directed from the grid to the filament. The permanent magnet or electromagnet of the magnetic field generation means is installed to generate a magnetic field so as to be orthogonal to the electric field applied between the grid and the substrate electrode, and selectively interacts with the magnetic field to selectively pass through the ion species passing through the filament portion. The purpose is to take in the substrate surface.

Here, taking a film of diamond-like carbon as an example, in order to remove ions of CH ₂ or less,
It suffices to separate charged particles having a mass less than or equal to mass m _CH3 and charged particles having a mass greater than m _{CH3 from the} following formula between the cylindrical substrate electrodes installed at the positions of radii r ₁ and r ₂ and the grid. The applied electric field V may be applied. V> {(eB ² ) / (8m _CH3 )} r ₁ ² {1- (r ₂ ² / r ₁ ² )} ² (1) Here, B was applied in the direction orthogonal to the electric field V. It is a magnetic field. By controlling the electric field, the magnetic field, or both, as represented by this equation, selective passage of ionic species is possible. Therefore, hydrogen atoms and the like, which are important from the viewpoint of accelerating the chemical surface reaction on the substrate surface, can reach the substrate without being affected by the magnetic field and electric field.

The fillant is for thermionic generation and is arranged between the source of material gas and the grid. The material gas supply source is a hollow cylinder with a multi-nozzle connected to the gas supply pipe, or as an evaporation source not connected to the gas supply pipe,
It is a crucible-shaped member formed of carbon, tantalum, tungsten, boron nitride, or the like, and is capable of vaporizing and releasing vaporized substances inside. The power supply means is a means for realizing a predetermined electric state in the vacuum chamber,
The power supply means and the inside of the vacuum chamber are electrically connected by a conductive means.

Next, in the thin film forming apparatus of the second aspect, in the thin film forming apparatus of the first aspect, with respect to the structure of the substrate electrode, the grid, the magnet, and the filament, two grids formed in a cylindrical shape are located from the center of the vacuum chamber. These two grids and magnets generate orthogonal electric and magnetic fields to promote the selective passage of ion species, and to re-accelerate the ion species selected by the substrate electrode and the grid located near the substrate electrode. Use a strict configuration. In this case, the power supply means is configured such that the grid on the center side of the vacuum chamber has a positive potential with respect to the filament, and the grid on the substrate electrode side is lower than the previous grid potential and higher than the substrate electrode. ..

Next, in the thin film forming apparatus of claim 3, in the thin film forming apparatus of claims 1 and 2, a function of atomizing hydrogen molecules in the hydrogen gas supply source before supplying the hydrogen gas into the vacuum chamber is provided. It has a configuration that incorporates an independent hydrogen atom supply mechanism. Further, in the thin film forming apparatus of claim 4, in the thin film forming apparatus of claim 1, claim 2, or claim 3, a multi-small-hole nozzle for accelerating the hydrogen atom flow released in the hydrogen atom supply mechanism is provided. To have.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. [Embodiment 1] First, an embodiment of claim 1 is shown in FIGS. FIG. 1 is a plan view of the reactor 12 of the thin film forming apparatus as seen from above, in which reference numeral 1 is a material supply source (material gas supply source or evaporation source), and reference numeral 2 is a hot filament. Reference numeral 3 is an accelerating electrode grid, reference numeral 4 is a substrate electrode (counter electrode), and reference numeral 5 is an outer wall of the vacuum chamber. 2 is a side sectional view of the reactor 12 of the thin film forming apparatus. Reference numerals 1 to 5 are the same as those in FIG.
Reference numerals a, 6b, 6c and 6d are means for generating a magnetic field and are permanent magnets or electromagnets. Reference numeral 7 is a means for supplying a material gas and is a gas line and a flow control valve.
Is a power supply for the hot filament, reference numeral 9 is a power supply for generating an accelerating electric field, and reference numeral 10 is a thin film formation substrate.

In the embodiment shown in FIGS. 1 and 2, the upper part of the reactor is detachable for mounting the substrate, and is mounted on the integrally formed side and lower parts through O-rings. The vacuum chamber 11 in the reactor is connected to an exhaust pump through an exhaust port provided in the lower part, and the exhaust pump can exhaust to a high vacuum state. Here, in order to remove the upper part of the reactor 12, the flow control valve part 7 and the power supply connection part for the filament grid are detachable. Also, the vacuum chamber 1
At the center of the inside of 1, there is installed a discharge part of the material gas supply source or evaporation source with a multi-nozzle as shown by reference numeral 1 in FIG. The filament 2, the grid 3, and the substrate electrode 4 are arranged at equal distances from the center of the vacuum chamber 11 and are connected and supported to the lower part of the reactor by a method not shown. Figure 2
An AC power supply 8 is connected to the filament 2, but this is not particularly limited to an AC power supply and may be a DC power supply. Further, the polarity is not limited when using the DC power supply. A DC power supply 9 is used for the grid, but with respect to its polarity, the grid 3
The power supply is arranged so as to have a positive potential with respect to. In FIG. 2, the potential applied to the substrate electrode 4 is the same as that of the filament 2. However, the potential is not particularly limited, and any bias potential may be applied.

In this device example, the potential of the substrate electrode 4 is made equal to the potential of the filament 2, and plasma that diffuses and moves between the grid 3 and the filament 2 and stabilizes between the grid 3 and the substrate electrode 4. It is known that various plasmas are generated (the state of the plasma generated in this space varies depending on the potential applied to the substrate electrode 4).
Here, a magnetic field orthogonal to the electric field applied between the grid 3 and the substrate electrode 4 is generated by the magnetic field generating means (permanent magnet or electromagnet) 6
To generate. Then, by controlling the power source 9 to control the electric field strength according to the equation (1), the ion species can be selectively taken into the substrate surface.

[Embodiment 2] Next, another embodiment of claim 1 is shown in FIG. FIG. 3 is a plan view of the reactor 12 of the thin film forming apparatus as seen from above. In FIG. 3, the grids and substrate electrodes denoted by reference numerals 3 and 4 are formed in a polygonal column shape, and are even from the center of the vacuum chamber 11. They are arranged at a distance and are connected to and supported by the lower part of the reactor in a manner not shown. Here, the number of angles of the polyhedron is not particularly limited. The other reference numerals are the same as the reference numerals in the first embodiment. Also,
The material gas supply system and the power supply system are also the same as those in the first embodiment. In Example 1, by adopting a single-type cylindrical electrode as the substrate electrode 4, it is possible to form a film on a flexible plastic substrate material or the like over a large area.
Then, by adopting a polygonal columnar electrode, ion species selective film formation can be simultaneously performed on a large number of flat substrates.

[Embodiment 3] Next, an embodiment of claim 2 is shown in FIG. FIG. 4 is a plan view of the reactor 12 of the thin film forming apparatus as seen from above, in which the reference numeral 3a is a first accelerating electrode grid and the reference numeral 3b is a second accelerating electrode grid. Reference numeral 4 is a substrate electrode. The grid 3a and the grid 3b generate an ion selective electric field region, and the grid 3
An accelerating electric field for re-accelerating the ion species selected by b and the substrate electrode is generated. In the drawing, other reference numerals are the same constituent members as in the first embodiment. In the structure of the third embodiment, the incident energy on the substrate surface can be controlled by maximally accelerating the selected ion species with the acceleration electric field between the grid 3b and the substrate electrode 4.

Next, although the embodiment of claim 3 is not shown,
According to the apparatus configuration of claim 3, in addition to the apparatus configurations represented in the above-described Examples 1, 2, and 3, an independent hydrogen atom supply unit is equipped with a multi-small-hole nozzle for accelerating a hydrogen atom flow. It is a thing. Although the embodiment of claim 4 is not shown, the device configuration of claim 4 is the same as that of the above-mentioned embodiments 1, 2,
In addition to the apparatus configuration represented in 3, the material gas supply unit is equipped with a hydrogen atom gun that independently has a hot filament and an accelerating electric field grid that can generate and supply a large amount of hydrogen atoms. By implementing these, it becomes possible to take in an arbitrary amount of hydrogen atoms, which are important for promoting the chemical reaction on the surface of the substrate, into the surface of the substrate.

[0018]

As described above, according to the thin film forming apparatus of the present invention, film formation requiring chemical reactivity on the surface of the substrate via hydrogen atoms, and ionic valency of incident substance on the substrate
In film formation that requires selection by mass, high energy can be electrically given by ionization of material and introduced gas and electric field acceleration (high electron / ion temperature), so heat to accelerate the reaction by heating the substrate. Film formation can be realized without giving energy, and selective film formation at low temperature becomes possible. Therefore, according to the thin film forming apparatus of the present invention, ion species selective film formation is possible, and a thin film having extremely strong adhesion to a substrate can be formed, and large area plastics having no heat resistance can be used as a substrate. It can be used. Further, according to the thin film forming apparatus of the present invention, a uniform film thickness and a uniform physical property can be obtained on a plurality of large area substrates in the selective film formation of ionic species with good adhesion and close to a stoichiometric composition. Since the thin film can be formed, it can be sufficiently applied to mass production.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of the invention according to claim 1, and is a plan view of a reactor of a thin film forming apparatus as seen from above.

FIG. 2 is a view showing an embodiment of the invention described in claim 1, and is a side sectional view of a reactor of a thin film forming apparatus.

FIG. 3 is a view showing another embodiment of the invention according to claim 1, and is a plan view of the reactor of the thin film forming apparatus as seen from above.

FIG. 4 is a view showing an embodiment of the invention described in claim 2, and is a plan view of the reactor of the thin film forming apparatus as seen from above.

[Explanation of symbols]

1 ... Material supply source (material gas supply source or evaporation source) 2 ... Filament 3 ... Grid 3a ... First grid 3b ... Second grid 4 ... Counter electrode (substrate electrode) 5 ... Outer wall of vacuum chamber 6a, 6b, 6c, 6d ... Magnetic field generating means (permanent magnet or electromagnet) 7 ... Material gas supplying means 8 ... Grid power supply 9 ... Filament power supply 10. ..Substrate on which thin film is formed 11 ... Vacuum tank 12 ... Reactor

Claims (4)

[Claims] 1. An active gas or an inert gas, or
A vacuum tank into which a mixed gas of these two is introduced, and a material supply source which is provided in the center of the vacuum tank in the vacuum tank and which is provided with a radiation nozzle to uniformly radiate a thin film forming gas material substance toward a substrate. Alternatively, a material supply source that vaporizes a solid material to be thin film-formed and uniformly radiates it toward the substrate, and a plurality of flat plate pairs that hold a plurality of thin-film-formed substrates arranged in a cylindrical shape along the inner wall of the vacuum chamber. An electrode or a single cylindrical counter electrode; a grid, which is arranged between the material supply source and the counter electrode and allows material to pass therethrough; and a grid between the material supply source and the grid A filament for thermoelectron generation arranged in a cylindrical shape, a means for making the grid a positive potential with respect to the filament, and a magnetic field in a direction orthogonal to an electric field direction generated between the grid and the counter electrode. Magnetic field generating means (a plurality of electromagnets or permanent magnets) to be generated, means for controlling the strength of the magnetic field, and means for heating the material supply source by electron bombardment by setting the material supply source to a positive potential with respect to the filament. A power source means for realizing a predetermined electric state in the vacuum chamber, and a conductive means for electrically connecting the vacuum chamber and the power source means, and the material is radially supplied from the material supply source. A thin film characterized by emitting a substance and controlling the strength of an electric field in the radial direction and the strength of a magnetic field orthogonal to the electric field so that ionic valence and mass can be selected to enable selective film formation of ionic species. Forming equipment. 2. The thin film forming apparatus according to claim 1, wherein a cylindrical second grid is provided between the grid and the counter electrode, and a magnetic field is applied so as to be orthogonal to an electric field generated between the grid and the second grid. Allows selection of additional ion species,
A thin film forming apparatus comprising a method of accelerating ion species to a substrate surface between a second grid and a counter electrode. 3. The thin film forming apparatus according to claim 1, wherein a hydrogen atom gun using a hot filament is installed in the center of the vacuum chamber in order to supply a high concentration of hydrogen atoms to the thin film forming substrate. A thin film forming apparatus. 4. The thin film forming apparatus according to claim 1, 2, or 3, wherein the thin film forming apparatus has a method of accelerating the nozzle by installing a nozzle at a radiation port of a hydrogen atom gun. ..