JPH0762244B2 - Film forming method by ion plating - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming method by ion plating.

[0002]

2. Description of the Related Art Generally, a film forming method by ion plating has a feature that a film having high adhesion can be formed on a surface of a substrate as compared with a usual CVD method and a sputtering method.
When applying the film formation method by ion plating having such characteristics to the structural material as the base material, the viewpoint of forming a thick film with a smooth surface without being affected by the improvement in productivity and the surface roughness of the structural material. Therefore, it is required to form a film at a high speed.

By the way, as a conventional film forming method by ion plating, a method disclosed in Japanese Patent Laid-Open No. 63-62872 is known. In such a film forming method, a film forming material in a crucible arranged in a vacuum chamber is irradiated with an electron beam to be evaporated, and plasma from a plasma gun provided on the side wall of the chamber is attached to the upper surface of a substrate holder in the upper part of the chamber. Is narrowed down to the base material held on the lower surface of the holder by the permanent magnet arranged in the above, and the evaporated film forming material is ionized by the plasma to form a film on the surface of the base material.

[0004]

However, in the above-described film forming method, since the plasma current flows through the substrate, the substrate temperature depends on the plasma current. Therefore, for the purpose of increasing the ionization rate of the vaporized substances introduced into the plasma,
Increasing the plasma current raises the substrate temperature. On the other hand, when the plasma current and the magnetic field of the permanent magnet are increased for the purpose of increasing the film formation speed, the plasma density near the surface of the base material increases, so that the thin film formed on the surface of the base material is sputtered and the film formation speed increases. descend. As a result, there is a problem that the substrate temperature and the film formation rate cannot be controlled independently, and the substrate temperature cannot be kept constant to increase the film formation rate. It should be noted that an increase in the substrate temperature during film formation causes a problem that it becomes difficult to form a film on a substrate made of a material having low heat resistance, and the material of the substrate is restricted.

The present invention has been made in order to solve the above-mentioned conventional problems, and it is a film formation by ion plating that achieves high-speed film formation on the surface of the base material while suppressing an increase in the base material temperature. It is intended to provide a method.

[0006]

SUMMARY OF THE INVENTION The present invention is a vacuum chamber.
And a substrate holder placed near the top of the chamber
It is placed near the bottom of the chamber and is steamed with an electron gun.
A vapor deposition source for evaporating the adhering substance and a side wall of the chamber
The plasma gun and the front of the inner wall of the chamber.
Located in the same or almost the same plane as the plasma gun
Placed so that it faces the plasma gun.
The plasma from the plasma gun into the chamber
Rectangular first counter electrode for drawing out, and the chamber
Near the inner surface of the side wall of the plasma gun
The electrons from the electron gun so that they are located in one plane
Arranged so as to face each other in the beam emission direction,
Extraction of plasma from plasma gun into the chamber
Rectangular shaped second and third counter electrodes for
3 so that the surface facing each other becomes the S pole.
The built-in permanent magnets and the counter electrodes are located
Are located near the outer surface of the side wall of the chamber.
A coil for controlling the magnetic force in relation to each magnet
And Bei draws plasma from the plasma gun within the chamber in the first to third counter electrode having the permanent magnets, at least the vaporized deposition material is ionized by the plasma negative potential is applied When forming a film on the surface of the base material, the magnetic flux density at or near the intersection of the straight line connecting the center of the base material and the center of the vapor deposition source and the plane where the plasma gun and the first to third counter electrodes are located. It is a film forming method by ion plating, which is characterized in that the minimum magnetic flux density is set to 18 Gauss or more. The vicinity of the intersection means a region projected from the base material and extending over half the distance from the center of the base material to the peripheral edge thereof.

The reason for limiting the minimum magnetic flux density is 18
This is because if it is less than Gauss, it is impossible to achieve high-speed film formation, that is, high-speed film formation of 50 Å (hereinafter referred to as A) / second or more. A more preferable minimum magnetic flux density is in the range of 25 to 100 Gauss.

The coating film formed on the surface of the base material is, in addition to the vapor deposition material, a desired compound coating film by introducing a reaction gas into the chamber and reacting with the vapor deposition material in the plasma. Can be formed on the surface of the base material.

[0009]

According to the present invention, in the vicinity of the upper part in the vacuum chamber
Holding the substrate by the holder, the evaporation source to evaporate the deposition material by an electron gun disposed near the bottom of the chamber, plasma
Located in the same or almost the same plane as the Ma gun and in front
How to emit an electron beam from a plasma gun and the electron gun
Are arranged in a predetermined positional relationship with the direction, and the facing surface is the S pole.
The plasma from the plasma gun provided on the side wall of the chamber is drawn into the chamber by the first to third counter electrodes having permanent magnets , and at least the vaporized deposition material is ionized by the plasma to have a negative potential. When a film is formed on the surface of the base material to which is applied, a straight line connecting the center of the base material and the center of the vapor deposition source, the plasma gun, and the first to
The magnetic flux density at or near the intersection with the plane where the third counter electrode is located is minimized, and the minimum magnetic flux density is set to 18
By setting it to be Gauss or higher, a sheet-like high density plasma can be generated near the lower part of the base material. As a result, by applying a negative potential to the substrate, most of the positive ion deposition material ionized in the high-density plasma can be deposited on the surface of the substrate. Therefore, high-speed film formation on the surface of the base material can be achieved while suppressing an increase in the base material temperature.

[0010]

Embodiments of the present invention will now be described in detail with reference to FIGS.

FIG. 1 is a schematic cross-sectional view showing an ion plating device used in the embodiment, FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1, and FIG. 3 illustrates plasma generation by the device. FIG. Reference numeral 1 in the figure denotes a square cylindrical vacuum chamber, and an exhaust pipe 2 communicating with a vacuum pump for maintaining a predetermined degree of vacuum in the chamber 1 is provided on an upper side wall of the chamber 1. . Further, 3 in the drawing is a vapor deposition source. The vapor deposition source 3 is based on the chamber 1
A crucible 4 installed at the bottom of the chamber 1, an electron gun 5 provided on the lower part of the side wall of the chamber 1 for irradiating the crucible 4 with an electron beam, and an electron gun 5 arranged near the upper part of the crucible 4. A pair of deflection magnets 6 for deflecting the electron beam from the substrate to irradiate the vapor deposition material in the crucible 4.
It consists of and.

A plasma gun 7 as a plasma generation source is provided on the outer surface of one side wall of the chamber 1, and an introduction for introducing a predetermined gas such as argon (Ar) into the rear portion of the plasma gun 7. A tube (not shown) is provided. A diaphragm coil 8 is provided on the outer surface of the side wall of the chamber 1 in which the plasma gun 7 is provided, and a plasma narrowing portion 9 is provided on the side wall. The three support shafts 10 ₁ , 10 ₂ , and 10 ₃ are located in the same plane as the plasma gun 7 on the other three sidewalls except the one sidewall on which the plasma gun 7 is provided. It is inserted through. Each of the support shafts 10 ₁ , 10 ₂ , 10 ₃
Counter electrodes 11 ₁ , 11 ₂ and 11 ₃ each having a rectangular shape are fixed to the tip located in the chamber 1. Of the counter electrodes 11 ₁ , 11 ₂ , and 11 ₃ , the counter electrode 11 ₁ faces the side wall on which the plasma gun 7 is provided. The remaining two counter electrodes 11 ₂ and 11 ₃
Are arranged so as to be parallel to each other, and the counter electrode 11 ₂ is arranged near the inner surface of the side wall of the chamber 1 in which the electron gun 5 is provided. Each of the counter electrodes 11 ₁ , 11 ₂ , and 11 ₃ has a rectangular shape of permanent magnets 12 ₁ , 12 ₂ , and 12 ₃ so that the surfaces facing each other are S poles.
Is built in. Each of the support shafts 10 ₁ , 10 ₂ , 10
Reference numeral ₃ is electrically connected to the plasma gun 7, and a DC power source 13 for applying a negative potential to the plasma gun 7 is interposed in the wiring connecting the respective members. The gun 7 and the respective counter electrodes 11 ₁ ,
A potential gradient can be applied between 11 ₂ and 11 ₃ . Three air-core coils 14 ₁ , 14 ₂ , 14 ₃ are provided in the vicinity of the outer surfaces of the other three side walls except the one side wall of the chamber 1 in which the plasma gun 7 is provided, and the counter electrodes 11 ₁ , 11 ₂ , It is arranged corresponding to 11 ₃ .

A holder 15 for holding a base material is provided in the vicinity of the upper part of the sheet-shaped plasma generation region in the chamber 1.
And the holder 15 is supported and suspended by a rotary shaft 16. The rotary shaft 16 is connected to a variable power source 17, and the holder 1 is passed through the rotary shaft 16.
A negative voltage is applied to 5. A reaction gas introducing pipe 18 is connected to a lower portion of a side wall of the chamber 1. Next, a method of forming a TiN coating film using the above-mentioned ion plating device will be described.

First, the substrate 15 made of SUS304 is held in the holder 15, Ti is stored in the crucible 4 of the vapor deposition source 3, and then a vacuum pump (not shown) is operated to exhaust the gas in the vacuum chamber 1 to the exhaust pipe 2. Gas is exhausted through the chamber 1 and the pressure in the chamber 1 is discarded to 1 × 10 ⁻⁵ torr, and then the gas introduction pipe 18
To supply N ₂ gas into the vacuum chamber 1 so that the N ₂ partial pressure is 3 × 10 ^{−3 to} 5 × 10 ⁻³ torr. Subsequently, the variable power source 17 is passed through the rotary shaft 16 and the holder 15 to form the base material 19.
While applying a negative voltage to the electron gun, an electron beam is emitted from the electron gun 5, and a pair of deflection magnets 6 irradiate the electron beam on Ti contained in the crucible 4 to melt and vaporize the Ti.
At the same time, when argon gas was supplied to the plasma gun 7 and plasma was generated from the plasma gun 7, the plasma gun 7 was arranged so as to face the plasma gun 7, and a power source 13 provided a potential gradient with the plasma gun 7. Three counter electrodes 11 ₁ ,
The plasma 20 is drawn out into the chamber 1 through the narrowed portion 9 by 11 ₂ and 11 ₃ . At this time, each of the counter electrodes 11 ₁ , 11 ₂ , and 11 ₃ has rectangular permanent magnets 12 ₁ , 12 ₂ , and 12 ₃ built-in so that the surfaces facing each other become S poles. Air core coil 1 is provided on the back surface of ₁ , 11 ₂ , 11 ₃ (near the outer surface of the side wall of chamber 1).
4 _1, 14 _2, 14 ₃ for is located, the respective magnets 12 ₁ below and in the vicinity of the holder 15 as shown in FIG. 3, 1
Strong magnetic fields (magnetic flux densities) B ₁ , B ₂ , and B ₃ are generated from the N pole on the back surface of 2 ₂ and 12 ₃ to the S pole on the facing surface. When such a magnetic field is generated, the plasma 20 extracted from the plasma gun 7 causes the magnetic flux densities B ₁ , B ₂ , B
_{Since the} magnets 12 ₁ , 12 ₂ , and 12 ₃ are entangled with each other and are drawn into the magnets 12 ₁ , 12 ₂ , and 12 ₃ , they become a sheet-like shape in the vicinity of the lower part of the holder 15 and have a high density. Also, the air-core coil 1
4 _1, 14 _2, by adjusting the amount of current supplied to the 14 _3, is a more powerful magnetic flux is generated, more densified sheet-shaped plasma is formed. Moreover, the planar shape of the sheet-shaped plasma 20 is controlled by adjusting the amount of current supplied to the air-core coils 14 ₁ , 14 ₂ , 14 ₃ .
When the sheet-shaped plasma 20 is generated, the magnetic flux density is the line connecting the center of the crucible 4 and the center of the holder 15, the plasma gun 7 and the counter electrodes 11 ₁ , 1 1.
The intersection with the surface formed by 1 ₂ and 11 ₃ becomes the minimum, and the magnetic flux density increases from the intersection to the magnets 12 ₁ , 12 ₂ and 12 ₃ . In other words, the density of the sheet-shaped plasma 20 is minimal at the intersection increases toward from said intersection to said magnet 12 _1, 12 _2, 12 _3.

When such a sheet-like plasma 20 having a high plasma density is generated near the lower portion of the holder 15 (base material 19), Ti vaporized by the vapor deposition source 3 rises in the plasma 20. The N ₂ gas supplied is efficiently ionized and the supplied N ₂ gas is also plasma 2.
Activated within 0. Ionized Ti (positive ion Ti) is accelerated toward the substrate 19 side to which the negative voltage is applied,
A TiN coating film is formed on the surface of the base material 19 at a high speed by colliding and reacting with the activated N ₂ .

At the time of the above-mentioned film formation, at the intersection of the line connecting the center of the crucible 4 and the center of the holder 15 and the surface formed by the plasma gun 7 and the counter electrodes 11 ₁ , 11 ₂ and 11 ₃ . The magnetic flux density and the plasma current were set to the conditions shown in Table 1 below, and the deposition rate of the TiN coating and the substrate temperature were measured. The results are also shown in Table 1 below. Table 1 No Magnetic Flux Density Plasma Current Film Deposition Rate Substrate Temperature (Gauss) (Amps) (A / sec) (° C) 1 15 60 30 300 2 19 70 50 50 400 3 25 220 220 210 500 4 4 26 250 280 500

As is clear from Table 1, the crucible 4
50 A by setting the magnetic flux density at the intersection of the line connecting the center of the holder and the center of the holder 15 and the surface formed by the plasma gun 7 and the counter electrodes 11 ₁ , 11 ₂ , and 11 ₃ to 18 Gauss or more. It can be seen that the TiN film can be formed at a high speed of not less than 1 second / second and that the rise in the substrate temperature can be suppressed.

For the TiN coating film formed under the conditions of No. 2 to No. 4, the critical load, hardness and EPM
The N / Ti ratio according to A was measured. As a result, the scratch critical load is 30 to 40 N, the Vickers hardness (10 g) is 2200 to 2700, and the N / Ti ratio is 80% or more, which is comparable to the TiN coating film formed by ordinary ion plating. It was confirmed to have. In addition, although the TiN coating film is formed in the above-mentioned embodiment, the same can be applied to the other metal coating, alloy coating, or compound coating.

[0019]

As described in detail above, according to the present invention, it is possible to form a desired coating film on the surface of the base material at a high speed while suppressing an increase in the base material temperature, and to be restricted by the material of the base material. In addition, it is possible to provide a film forming method by ion plating that exhibits remarkable effects such as improved productivity and formation of a thick film having a smooth surface without being affected by the surface roughness of the structural material.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an ion plating device used in Examples.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a perspective view for explaining generation of plasma by the ion plating apparatus of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vacuum chamber, 3 ... Vapor deposition source, 4 ... Crucible, 5 ... Electron gun, 7 ... Plasma gun, 11 ₁ , 11 ₂ , 11 ₃ ... Counter electrode, 12 ₁ , 12 ₂ , 12 ₃ ... Permanent magnet, 14 ₁ , 14
₂ , 14 ₃ ... Air core coil, 15 ... Holder, 17 ... Variable power supply, 18 ... Gas introduction pipe, 19 ... Base material, 20 ... Plasma.

Claims (1)

[Claims] 1.Vacuum chamber and upper part in said chamber
Substrate holder located near and bottom in the chamber
A vapor deposition source that is placed nearby and uses an electron gun to vaporize the vapor deposition material.
And a plasma gun provided on the side wall of the chamber,
If the same as the plasma gun is used near the inner surface of the side wall of the chamber.
Or the above-mentioned plasma
Arranged to face the Ma gun, from the plasma gun
A rectangular first for drawing plasma into the chamber.
1 the counter electrode and the plug near the inner surface of the side wall of the chamber.
To be in the same or almost the same plane as the Zuma gun
And in the direction of electron beam emission from the electron gun
Plas from the plasma gun, arranged to face each other
2nd and 2nd rectangular shapes for pulling the chamber into the chamber
3 counter electrodes and the first to third counter electrodes
Permanent magnets built in so that the facing surface becomes the S pole
Stones and outside the sidewall of the chamber where each counter electrode is located
It is arranged near the surface and the magnetic force is generated in relation to each magnet.
And a coil for controllingIs it the plasma gun?
These plasmasThe aboveHave a permanent magnetFirst to thirdOpponent
Electrodes lead into the chamber and at least the evaporation
The deposited material is ionized by the plasma and a negative potential is generated.
When forming a film on the surface of the applied substrate,  The straight line connecting the center of the substrate and the center of the vapor deposition source and the plasma
A plane in which the Ma gun and the first to third counter electrodes are located
Magnetic flux density at or near the intersection of
The minimum magnetic flux density of is set to 18 Gauss or more
And a film forming method by ion plating.