JP2002167659A - Method and system for depositing chromium carbide thin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base plate having excellent wear resistance, adhesion, corrosion resistance and heat resistance by applying a thin film of chromium carbide to the surface of a base plate composed of cemented carbide or tool steel and used for dies and tools. SOLUTION: A vacuum chamber 2 has: an evaporation source 6 consisting of an electron gun 12 and a rotatable crucible where an annular part 8b of a doughnut-like hearth 8a is filled with a chromium evaporation material 10; and base plates T attached to a plurality of base-plate holders 50 provided to the outer peripheral part of a discoid plate 42 rotating in the vertical direction of the evaporation source 6. In the vacuum chamber 2, the base plates T are cleaned, and then, the above chromium evaporation material 10 is evaporated by the irradiation of an electron beam 14 from the electron gun 12 while rotating the above base plates T and further rotating the crucible 8 and, simultaneously, hydrocarbon type reactant gas is introduced to deposit the thin film of chromium carbide onto the above rotating plurality of base plates T.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a chromium carbide (C)
rC) The present invention relates to a method and an apparatus for forming a thin film.
The present invention relates to a method and an apparatus for forming a chromium carbide thin film capable of imparting wear resistance, high corrosion resistance, high heat resistance, and the like.

[0002]

2. Description of the Related Art In order to protect base metals such as cutting tool steel, alloy tool steel, and cemented carbide, and to increase properties such as corrosion resistance, heat resistance and wear resistance, a ceramic coating is applied to the surface of these base materials. , TiN, iC, TiCN, AlTi
Up to now, coating with a thin film such as N, CrN, or DLC (diamond-like carbon) has been widely performed.
The coating film is selectively coated according to physical properties such as heat resistance, adhesion, and hardness required of the base material.

[0003]

In forming such a thin film on the surface of a base material, various film forming apparatuses are known. Above all, a high vacuum arc discharge type ion plating apparatus (hereinafter referred to as an ADIP apparatus) is widely used. However, although thin films such as TiN, TiC and TiCN can be formed by this ADIP apparatus, it is difficult to form thin films such as AlTiN, CrN and DLC.

A thin film of TiN, TiC, TiCN or the like formed on the surface of an iron-based material by an ADIP apparatus has a low heat-resistant temperature of about 450 ° C. in an air atmosphere. However, both the cutting speed and the feed rate are inappropriate in the direction of high load. Similarly, it is unsuitable as a surface film for a mold or the like used at a high temperature. Further, it has been pointed out that even if there is no defect on the surface of the thin film, there is a problem that rust of the underlying substrate is generated depending on the humidity and the film forming conditions.

In the ionization by the ADIP apparatus, the vaporized material is made into particles and ionized using the vapor pressure of the evaporation source. In the case of binary nitrides such as AlTiN, materials having only a high melting point side are preferentially ionized in a material having a difference in evaporation source temperature at which a constant vapor pressure is obtained, so that the obtained thin film has poor physical property controllability. In addition, since the ions generated by ADIP are ions generated by evaporation source ionization, the ionization efficiency of the introduced gas is low. For this reason, it is practically difficult to form a gas ionization rate controlling substance such as CrN or AlN, which is formed by a reaction gas ion rate controlling substance. In addition, DLC
In this method, when the graphite is evaporated by electron beam evaporation to generate an arc discharge, a high-quality DLC cannot be obtained because the material becomes a cluster (clustering) typified by fullerene such as C60. As described above, it is particularly difficult to form a CrN film having high adhesion and high corrosion resistance, an AlTiN film having high heat resistance, and the like.
The thin film formation by the P apparatus has been performed only on a base material for a limited use.

In view of the above, the present invention provides a chromium carbide (CrC) having all of the properties such as the high adhesion and high corrosion resistance of a CrN film and the high heat resistance of an AlTiN film.
It is an object of the present invention to provide a film forming method and a film forming apparatus capable of forming a film.

[0007]

According to a first aspect of the present invention, there is provided a method for forming a chromium carbide thin film, wherein a donut-shaped hearth is filled with an evaporating material, and a rotatable crucible and an electron gun. A substrate attached to a plurality of substrate holders having an outer peripheral portion of a disc-shaped plate that rotates in the vertical direction of the evaporation source, and in a vacuum chamber in which a bombardment process of the substrate is performed, then rotating the substrate, Further, while rotating the crucible, the evaporation material in the crucible hearth is evaporated by the impact of the electron beam irradiated from the electron gun, and a reaction gas is introduced to form a chromium carbide thin film on the rotating substrate. Features.

According to a second aspect of the present invention, in the film forming method of the first aspect, the evaporation material has a sublimability of 1 to 3 m.
The invention according to claim 3, wherein the metal chromium is m-diameter granular metal chromium, the reaction gas according to claim 1 is a hydrocarbon-based gas having 1 to 4 carbon atoms in a molecule. And

According to a fourth aspect of the present invention, there is provided a rotating crucible in which a donut-shaped hearth is filled with an evaporating material and an electron gun, which are arranged near a lower part of a vacuum chamber whose inside is evacuated by an evacuating means. Substrates attached to an evaporation source and a number of substrate holders equidistantly arranged on an outer peripheral portion of a disk-shaped plate attached to one of the side walls in the vacuum chamber via a revolving mechanism so as to rotate in the vertical direction of the evaporation source. A thermionic emission filament disposed above the evaporation source in the vicinity of the irradiation range of the electron beam irradiated from the electron gun; an ionization electrode disposed above the thermionic emission filament; At least one reaction gas is introduced into the
An apparatus for forming a chromium carbide thin film, comprising: one reaction gas introduction pipe; and a substrate heating heater disposed below the evaporation source.

According to a fifth aspect of the present invention, in the film forming apparatus of the fourth aspect, the evaporating substance has a sublimability of 1 to 3 m.
According to a sixth aspect of the present invention, the reaction gas introduction tube is outside the range of irradiation of an electron beam from an electron gun, and the tip of the reaction gas introduction tube is made of a granular metal chromium having an m diameter. At least one is disposed in the direction of the substrate. Further, in the invention according to the seventh aspect, in the film forming apparatus according to the fourth aspect, the reaction gas is 1 to 4 in a molecule.
It is a hydrocarbon-based gas having carbon atoms.

According to the first aspect of the present invention, the metal chromium in the crucible is evaporated by the impact of the electron beam from the electron gun in the evacuated vacuum chamber. The evaporated particles are ionized by the impact of thermionic electrons emitted from the thermionic emission filament, accelerated by the ionizing electrode, and collide with the substrate. At the same time, the hydrocarbon gas introduced into the vacuum chamber as a reaction gas is also ionized and directed toward the substrate, and chemically reacts with chromium to form a chromium carbide (CrC) film having good adhesion on the substrate.

In forming the chromium carbide (CrC) film, a crucible filled with chromium metal is rotated and used, so that a uniform and wide evaporation surface is maintained while evaporating chromium metal by an electron beam. Chromium can be evaporated, and a chromium carbide film having a uniform film thickness can be formed on a plurality of rotating substrates. In addition, by using sublimable metal chromium as an evaporation material in the form of granules having a diameter of 1 to 3 mm, evaporation by the impact of an electron beam can be effectively performed. Further, the supply of the consumed amount of the chromium metal can be easily performed.

According to the fourth aspect of the present invention, the vacuum chamber has a donut-shaped water-cooled hearth inside,
A crucible having an annular portion filled with an evaporating material and an electron gun below the crucible to serve as an evaporation source, and rotating the crucible; and a revolving mechanism provided near one side wall in a vacuum chamber. A plurality of substrates are mounted on a substrate holder having a rotating disk-shaped plate, and the substrates are rotated in the vertical direction of the evaporation source. Thus, a large amount of chromium can be evaporated, and a chromium carbide film can be formed on a plurality of rotating substrates at a uniform and stable film forming rate.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A film forming method and a structure of a film forming apparatus according to the present invention will be described below in detail with reference to the drawings. FIG.
FIG. 1 is a schematic explanatory view of a film forming apparatus according to the present invention. In the figure, reference numeral 2 denotes a vacuum tank, which is not shown through an exhaust port 4 below the vacuum tank. It is connected to the. The vacuum chamber 2 is evacuated to about 10 ⁻² to 10 ⁻⁵ Pa by these vacuum pumps. An evaporation source 6 provided with a copper crucible 8 and an electron gun 12 is disposed at a lower portion in the vacuum chamber 2. The crucible 8 has a hearth 8a inside, and the hearth 8a is hollow inside and has widths H ₁ and H ₂ outside 50 as shown in an enlarged view in FIG.
A donut-shaped annular portion 8b of mm is formed.
The donut-shaped annular portion 8b is filled with sublimable granular metallic chromium having a diameter of about 1 to 3 mm as the evaporation material 10. The crucible 8 is attached to a constant-speed crucible rotation motor 16 outside the vacuum chamber 2 at the bottom thereof.
a, so as to make a horizontal rotation of 1 to 10 rotations / hour.

The electron gun 12 has a ring portion 8b of the hearth 8a.
The surface of the granular metal chromium 10 filled therein is irradiated with the electron beam 14 and impacted, and the surface is scanned to evaporate the metal chromium. The vacuum chamber 2 and the crucible 8 are grounded. The irradiation range of the electron beam 14 is about 50 × 50 mm at the maximum, and is the same as the widths H ₁ and H _{2 of} the annular portion 8b described above.

One side of the vertical direction of the evaporation source 6 provided below the vacuum chamber 2 is fixed to a rotation shaft 48a of a substrate rotation motor 48 outside the vacuum chamber 2 and is evaporated by a revolving mechanism described later. A disk-shaped plate 42 rotating in the vertical direction of the source 6
Is arranged. On the outer peripheral portion of the disk-shaped plate 42, as shown in FIG. 3, a large number (36 in FIG. 3) of substrates or works (for example, tools, hereinafter referred to as substrates) T supporting substrates or works (hereinafter referred to as substrates) T The holder 50 is attached so as to face the evaporation source 6. The distance from the evaporation source 6 when the substrate T supported by the substrate holder rotates and faces the upper surface with the evaporation source 6 is preferably 350 mm or more.

On the substrate T, a D provided outside the vacuum chamber 2 is provided.
A voltage of 0 to -600 V is applied to the substrate T through the disk-shaped plate 42 and connected to the C bias power supply 36.
The substrate T can be heated up to about 700 ° C. by a heater 18 disposed below the evaporation source 6. The other end of the bias power supply 36 is grounded.

Reference numeral 20 denotes a thermionic emission filament. The thermoelectron emission filament 20 is provided above the crucible 8 in the vicinity of the irradiation area 14a of the electron beam 14 which is irradiated from the electron gun 12 and impacts and evaporates the evaporation material 10 in the crucible hearth. This thermionic emission filament 2
Reference numeral 0 denotes a material having a high melting point of about 1.0 mmφ, for example, a hot cathode material such as tungsten, molybdenum or tantalum, and both ends thereof are led out of the vacuum chamber 2 and have a capacity of, for example, 10 V and 100 A. It is connected to the filament heating power supply 22 and has a direct current of -5 to -6.
It is biased to a negative voltage of 0V. A filament bias power supply 24 is provided between one electrode of the filament heating power supply 22 and the ground. The filament bias power supply 24 is connected such that the heating power supply 22 side is negative and the ground side is positive.

Above the thermionic emission filament 20, an ionization electrode 26 is disposed. The ionization electrode 26 is formed of a high melting point material, for example, tungsten, molybdenum, tantalum or carbon, and has a rod or plate shape, for example, 20 × 100 × 3.
0 mm. Both ends of the ionization electrode 26 are led out of the vacuum chamber 2 and connected to a heating power supply 28 for the ionization electrode, and are maintained at a positive voltage of +5 to +100 V.

Reference numeral 32 denotes a reaction gas introduction pipe for introducing a reaction gas into the vacuum chamber 2, and a flow control valve 32 outside the chamber.
a. Since the irradiation widths H ₁ and H ₂ of the electron beam 14 from the electron gun 12 are each 50 mm at the maximum, the reaction gas introduction pipe 32 is located at a position of 50 mm × 200% = 100 mm from the center of the evaporation source. The height of 10 to 200 mm above the surface of the granular metal chromium 10 filled in the annular portion 8b of the hearth 8a and the direction thereof is flat outside the circle drawn as Facing the substrate side with respect to the evaporating surface of the evaporating material filled into the substrate, the inclination thereof is about 30 °,
That is, it is preferable that the evaporation material be out of the irradiation range of the electron beam.

The position of the reaction gas inlet tube 32 is specified as described above because the evaporation material becomes evaporation particles by the impact of the electron beam, and the thermoelectrons emitted from the thermoelectron emission filament 20 are applied by the ionization electrode 26. This is because an abnormal discharge due to the reaction gas is likely to occur during the process of ionizing the evaporated particles accelerated by the applied voltage +5 to 100 V, and the evaporation rate may be reduced. In addition, when the size of the substrate on which the film is to be formed becomes large, there is a possibility that the supply of the reaction gas from one reaction gas introduction pipe may become non-uniform. For this reason, one reaction gas introduction pipe is used when the size of the substrate is up to φ150 mm, two pipes are used up to φ150 to 300 mm, and φ300 to φ300.
The substrate diameter is 150mm, like 3 pieces up to 450mm
It is preferable to increase the number of reaction gas introduction pipes as the size of the reaction gas inlet increases. When the plurality of reaction gas introduction tubes are used, the installation position is outside the irradiation range of the above-mentioned evaporating material by the electron beam, and when two are used, the position is ± 75 mm across the crucible in the electron beam traveling direction. In the case of three wires, one wire is placed near the crucible in the electron beam traveling direction, and ±
It is preferable that the position be 15 mm. Reference numeral 34 denotes a slidable shutter provided between the substrate T and a portion related to the plasma generating mechanism and the evaporation source in the vacuum chamber 2.

In the present invention, as a substrate on which a chromium carbide thin film is formed, a hard metal (WC), alumina (Al ₂ O ₃ ), Cr, TiN or the like is used in addition to iron.

Next, the revolving mechanism of the apparatus of the present invention will be described with reference to a partially enlarged view of FIG. The revolving mechanism includes a fixed gear 4 having revolving gears 46 at both ends.
0, a disk-shaped plate 42, and a substrate rotation introducing plate 44. The fixed gear 40 is provided on one side wall 2 a of the vacuum chamber 2.
Is fixed by a fixed insulator 40a. Revolution gears 46 are attached to both ends of the fixed gear 40, and a disc-shaped plate 42 having a large number (for example, 36) of substrate holders 50 attached to the outer periphery of the revolution gear 46 via a shaft 52. Have been. The disk-shaped plate 42 is connected to a substrate rotating motor 48 outside the vacuum chamber 2.
Are fixed to both ends of a substrate rotation introducing plate 44 whose center is connected to the shaft end of the rotating shaft 48a by fixing insulators 44a.

Accordingly, when the motor 48 is started and the substrate rotation introducing plate 44 is rotated by the rotation of the motor rotation shaft 48a, the disk-shaped plate 42 is rotated in conjunction therewith, and attached to the outer peripheral portion of the disk-shaped plate 42. The large number of substrate holders 50 rotate (revolve) around the evaporation source disposed at a lower position in the vacuum chamber 2 at equal intervals.

In the revolving mechanism described above, the revolving gears 46 provided at both ends of the fixed gear 40 are used as the revolving gears, and the revolving gear 46 is provided with a mechanism capable of introducing the revolving rotation to the disc-shaped plate 42. If such a rotation shaft support mechanism 54 is provided between the rotation gear and the shaft 52 connecting the disk-shaped plate 42, the disk-shaped plate is interlocked with the rotation of the substrate rotation introduction plate 44 by the start of the motor. A large number of substrate holders 50 provided on the disk-shaped plate 42 can be rotated on their own by utilizing the force of the revolving rotation of the 42.

An example of the formation of a chromium carbide thin film by the film forming apparatus of the present invention whose structure is schematically shown in FIG. 1 will be described briefly. First, a 50 mm-width annular ring of a donut-shaped water-cooled hearth 8a of a crucible 8 in an evaporation source 6 is formed. The granular material 10 of 1-3 mm in diameter of chromium metal, which is an evaporating material, is placed in the portion 8b, a required number of substrates T are mounted on the substrate holder 50 of the disk-shaped plate 42, and then the vacuum chamber 2 is evacuated. After that, Ar gas is introduced into the vacuum chamber 2 from the reaction gas introduction pipe 32,
After applying a negative voltage to the substrate T to clean the substrate T by glow discharge bombardment, a film is formed. In this film formation, first, the disk-shaped plate 42 on which the substrate T is set is rotated by the revolving mechanism, and the chromium in the crucible 8 is preheated by the irradiation of the electron beam 14 by the electron gun 12 while simultaneously rotating the crucible 8. Thereafter, a current is supplied to the thermionic emission filament 20 and a positive voltage is applied to the ionization electrode 26, and the electron gun 12 is operated to evaporate chromium. In this state, the chromium evaporation particles are ionized, and plasma is formed. In this state, a hydrocarbon gas is introduced into the vacuum chamber 2. As a result, the evaporated chromium ions rise and adhere to the rotating substrate T, and at the same time, hydrocarbon gas and hydrocarbon-based decomposition products generated by the plasma are attracted to the substrate T to which the bias voltage is applied, and collide with the substrate T. I do. As a result, a CrC film is formed as a reaction product film on the surface of the substrate T.

In the above description, when a chromium carbide (CrC) thin film is formed using chromium metal as an evaporating material, CH ₄ , C ₂ H ₆ , C ₂ H ₂ , C ₂ H are used as reaction gases.
_4, although carbon as C ₃ H ₈ or C ₄ H ₈ can be used 1-4 hydrocarbon gas, among others C ₂
H ₆ gas and C ₂ H ₂ gas are preferred.

Thus, the ion of the chromium particles and the carbon ion
Reacts and traces a trace of carbon-containing Cr-rich thin film on the substrate.
(Hardness 500-1000Hk), Cr_ThreeC_TwoThin film (15
00 to 2500Hk), Cr₇C_ThreeThin film (1500-2
500Hk) or Cr _{twenty three}C₆Thin film (1000-2
000Hk), etc. with a thickness of about 0.1 to 50 μm
A chromium thin film can be formed.

Further, a chromium carbide film having these compositions can be obtained containing 15% by weight or less of hydrogen therein. This is obtained by introducing hydrogen generated when a hydrocarbon gas is decomposed during a film forming operation using Cr and a hydrocarbon reactive gas.

According to the film forming method of the present invention, the above-mentioned trace carbon-containing Cr-rich thin film, Cr ₃ C ₂ thin film, Cr ₇ C
₃ thin, or not only one chromium carbide thin films of the Cr ₂₃ C ₆ film, and the use of the reactive gas and argon gas as described above in the film-forming operation, the introduction amount of the hydrocarbon-based gas to the Cr from zero By gradually increasing the Cr film, a Cr-rich CrC film of several stages having different composition ratios of Cr and C is formed on the substrate,
A multilayer film having a gradient composition structure of a chromium carbide thin film such as ₃ C ₂ , Cr ₇ C ₃ , or Cr ₂₃ C ₆ can be obtained. In these cases, each film thickness is 0.0
2-1 μm is preferred.

In any of the above-described chromium carbide thin film formations, it is preferable to perform an annealing treatment after completion of the film formation in order to eliminate the adhesion between the formed thin film and the substrate and the distortion of the film. By this treatment, hydrogen accumulated in the film during film formation on the substrate can be removed, and the crystallinity can be further improved. This annealing treatment is performed in a vacuum chamber for 1 hour.
In an atmosphere of a hydrocarbon-based gas of about × 10 ^-1 Pa, 200
It is preferable to carry out in the range of -700 ° C.

According to the film forming apparatus of the present invention described above, the crucible in which the evaporating material is filled in the annular portion of the donut-shaped water-cooled hearth having a width of about 50 mm is rotated, so that the evaporating surface area of the evaporating material is reduced. In addition to being wide, a uniform evaporation surface can be maintained, and a film can be stably formed on a substrate for a long time. For this reason, even if a crucible filled with the same amount of Cr evaporating material is used, a conventional fixed crucible cannot be used.
Although the evaporation of about 00 g of Cr was the limit, the rotary crucible of the present invention can evaporate a large amount of about 500 g of Cr. Therefore, even if a plurality of rotating substrates are arranged in the vertical direction of the rotating crucible, a film having a uniform thickness can be stably formed.

Actually, Cr evaporation by electron beam irradiation was performed using both crucibles filled with Cr evaporating material, and the relationship between the film forming time and the film forming rate was obtained. In the crucible, stable film formation is only 10 minutes from the start of evaporation, whereas in the rotating crucible of the present invention, stable film formation is about 9 minutes.
It was observed to take place over 0 minutes. Therefore, the film thickness can be increased in a short time, and the obtained chromium carbide thin film has a high oxidation resistance of 800 ° C. or higher. Is good, and diffusion of carbon and iron-based material is easy to occur, so that adhesion to iron-based material can be expected,
It has such a feature that peeling does not occur even with a film thickness of 10 μm or more.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a film forming method using the film forming apparatus of the present invention will be described below.

Embodiments 1 to 4 First, in the apparatus shown in FIG. 1, 36 substrate holders 50, 5
0, six substrate holders 5 as shown in FIG.
The substrate T was set at 0, 50... As R-1 to R-6. In addition, in the annular portion 8b (width 50 mm) of the hearth 6a of the crucible 8 below the vacuum chamber 2, 1
It is filled with granular metallic chromium having a diameter of about 3 mm. The crucible 6 is connected to a constant-speed crucible rotation motor 16 outside the vacuum chamber 2 by a shaft 16a, and can be rotated horizontally at 1 to 10 rotations / hour. further,
One of the reaction gas introduction pipes 32 was disposed at a position outside the electron beam irradiation range with its tip directed toward the substrate.

After setting each member and the evaporating material in the vacuum chamber 2 as described above, an oil rotary pump, an oil diffusion pump, and the like (not shown) connected to the exhaust port 4 at the lower part of the vacuum chamber 2 are provided. Evacuation was performed to about 6.7 × 10 ⁻³ Pa by a vacuum pump. Next, while continuing the evacuation, the heater 1
In 8, the substrate T was heated to about 300 ° C. At the same time, while rotating the crucible 8 at 3 revolutions / hour, the electron gun 12 with the output of 2 kW is activated, and the irradiation area 30 ×
Preheating of the chromium evaporating material 10 in the crucible 8 at 50 mm
Time went.

Thereafter, the electron gun is stopped and the reaction gas introduction pipe 3 is turned off.
Ar gas was introduced from 2 and the pressure in the vacuum chamber 2 was set to 2.7 ×
At about 10 ^-1 Pa, a negative voltage of -500 to 1000 V was applied to the substrate T by the bias power supply 36 to cause glow discharge, and the surface of the substrate was cleaned for about 20 minutes.

Next, the introduction of Ar gas was stopped, and 6.7 × 1
After performing high vacuum evacuation to about 0 ^-3 Pa,
The chromium evaporating material 10 was preheated for 3 minutes by an electron gun 12 having an output of 2 kW and an electron beam 14 having an irradiation range of 30 × 50 mm while rotating at a rate of rotation / hour.

Next, ethane (C ₂ H ₆ ) gas was used in Examples 1 to 3, and acetylene (C ₂
Using H ₂ ) gas, each film was formed under the film forming conditions shown in Table 1. After the film formation, each power supply was turned off, the rotation of the crucible was stopped, and cooling was performed with high vacuum evacuation of about 6.7 × 10 ⁻³ Pa. The substrate was taken out.

[0040]

[Table 1]

The chromium carbide film obtained in the above embodiment is made of Cr
Rich, when which of _{Cr 3 C 2, Cr 7 C} 3, Cr 23 C 6 were investigated by X-ray diffraction, the result of FIG. 6 is obtained, Examples 1-3 as a reactive gas is C ₂ H ₆ gas, example 4 using C ₂ H ₂ gas, the electron gun also the conditions such as the output and the reaction gas pressure, the thin film only in example 1 changing the energization condition of the ionization electrode is Cr ₇ C _3, The thin film of Example 2 was Cr ₂₃ C ₆ , the thin film of Example 3 was a Cr-rich film,
Was found to be Cr ₃ C ₂ .

Example 5 In the same manner as in Examples 1-4, each member and the substrate were cleaned by glow discharge in a vacuum chamber in which the evaporating material was set.
After preheating the evaporating material, 25 A at 20 V ionization electrode and 10-30 at 20 V filament bias.
A, thermionic emission filament 10V at 60A and at constant conditions of substrate bias -200 V,, using C ₂ H ₆ gas, the reaction gas introduction pressure, the deposition time When a chromium carbide thin film was formed by setting as follows, a Cr film was formed on the substrate in (1), then a Cr-rich chromium carbide film in four steps in (2) to (5), and finally (6). With Cr
_By continuously increasing the ratio of C ₂ H ₆ gas to Cr, ie, ₇ C ₃ film, from 0, a Cr ₇ C ₃ film having a gradient composition structure of Cr and C could be formed. .

[0043]

As described above, according to the present invention, in a vacuum chamber, a crucible having a donut-shaped water-cooled hearth in which an annular portion is filled with an evaporating material and an electron gun below the crucible are provided. A plurality of substrates were mounted on a substrate holder provided on a disk-shaped plate provided near one side wall in a vacuum chamber and rotated by a revolving mechanism, wherein the evaporation source was provided, and the crucible was rotated. That the substrate is rotated in the vertical direction of the evaporation source,
A large amount of chromium can be evaporated while maintaining a uniform and wide evaporation surface when evaporating metal chromium by electron beam irradiation, and a chromium carbide film can be formed on a plurality of rotating substrates at a uniform and stable film forming rate. It can be formed.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of a film forming apparatus of the present invention.

FIG. 2 is an explanatory view showing an embodiment of a rotary crucible.

FIG. 3 is an explanatory diagram showing an example of a substrate holder arrangement on the outer periphery of a disk-shaped plate.

FIG. 4 is an explanatory diagram of a revolution mechanism.

FIG. 5 is an explanatory diagram showing a relationship between a film forming time and a film forming speed.

FIG. 6 is an X-ray diffraction diagram specifying the composition of a chromium carbide film obtained according to the present invention.

[Explanation of symbols]

 T substrate 2 Vacuum tank 6 Evaporation source 8 Crucible 8a Hearth 8b Annular part 10 Cr evaporation material 12 Electron gun 14 Electron beam 20 Thermoelectron emission filament 26 Ionization electrode 32 Reaction gas introduction tube 42 Disc-shaped plate 44 Substrate rotation introduction plate 48 Substrate Rotary motor 50 Substrate holder

Claims (7)

[Claims] An evaporating source comprising a rotatable crucible and an electron gun filled with an evaporating material in a donut-shaped hearth, and a plurality of substrates provided on an outer peripheral portion of a disk-shaped plate rotating in the vertical direction of the evaporating source. After the substrate attached to the holder and in a vacuum chamber where the substrate is placed, after bombarding the substrate, the substrate is rotated, and the crucible is further rotated. A method of forming a chromium carbide thin film, comprising evaporating an evaporating material in a crucible hearth, introducing a reaction gas, and forming a chromium carbide thin film on the rotating substrate. 2. The method according to claim 1, wherein the evaporating material is granular metallic chromium having a diameter of 1 to 3 mm and having sublimability.
3. The method for forming a chromium carbide thin film according to item 1. 3. The method for forming a chromium carbide thin film according to claim 1, wherein the reaction gas is a hydrocarbon-based gas having 1 to 4 carbon atoms in a molecule. 4. An evaporation source, which is disposed near a lower part of a vacuum chamber whose inside is evacuated by an exhaust means and includes a rotating crucible filled with an evaporation material in a donut-shaped hearth, and an electron gun; A substrate attached to a number of substrate holders equidistantly arranged on an outer peripheral portion of a disk-shaped plate attached to one side wall in a vacuum chamber via a revolving mechanism so as to rotate in a vertical direction, and above the evaporation source. Then, a thermionic emission filament arranged near the irradiation range of the electron beam emitted from the electron gun, an ionization electrode arranged above the thermoelectron emission filament, and a reaction gas are introduced into the vacuum chamber. At least one reaction gas inlet tube;
A substrate heating heater disposed below the evaporation source,
An apparatus for forming a chromium carbide thin film, comprising: 5. The evaporating material is sublimable granular chromium metal having a diameter of 1 to 3 mm.
2. The apparatus for forming a chromium carbide thin film according to claim 1. 6. The reaction gas introduction pipe according to claim 4, wherein at least one of the reaction gas introduction pipes is located outside the electron beam irradiation range from an electron gun and has a tip portion directed toward the substrate. Chromium carbide thin film deposition equipment. 7. The apparatus for forming a chromium carbide thin film according to claim 4, wherein the reaction gas is a hydrocarbon-based gas having 1 to 4 carbon atoms in a molecule.