JP2000199061A - Electronic cyclotron resonance plasma sputtering device, and manufacture of thin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-target device without increasing the size or complicating the shape of the device by providing a rotatable shield plate on the inner surface side of a cylindrical target formed by combining a plurality of targets. SOLUTION: A cylindrical target 11 comprises a backing plate 13 formed in polygonal shape, and a plurality of approximately rectangular flat targets 14 arranged on an inner surface of the backing plate. The cylindrical target 11 is provided with a plurality of shield plates 15 arranged on its inner surface side in a rotatable manner from the targets 14 keeping the specified distance therebetween. An electronic cyclotron resonance plasma sputtering device is capable of shielding a specified target by the shield plate 15, and achieves its purpose, forms a thin film which is uniform and high in purity on a substrate by appropriately controlling the rotation of the shield plate 15, and easily forms a multi-layer thin film having a steep interface or a thin film of functionally gradient material on the substrate with excellent quality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an electron cyclotron resonance plasma sputtering apparatus. The present invention also relates to a method for producing a thin film by an electron cyclotron resonance plasma sputtering method.

[0002]

2. Description of the Related Art An electron cyclotron resonance plasma sputtering apparatus (hereinafter referred to as an ECR plasma sputtering apparatus).
Is an electron cyclotron resonance (Electron Cyclotron Res
(Eon plasma), an electron cyclotron resonance plasma (hereinafter referred to as ECR plasma) is generated under this condition.
This is an apparatus for performing sputter film formation using ions generated by plasma.

An ECR plasma sputtering apparatus generates low-pressure, high-density plasma utilizing electron cyclotron resonance absorption of circularly polarized microwaves traveling along the magnetic field line of an external magnetic field of 875 gauss, thereby achieving low energy and large current density. It is possible to perform ion assist.

In an ECR plasma sputtering apparatus,
The interaction between the magnetic field of 875 gauss and the microwave of 2.45 GHz causes cyclotron motion of the electrons and increases the ionization probability of the sputtering gas, so that a stable ECR plasma can be obtained under a high vacuum. Then, the ECR plasma is extracted while maintaining neutrality by the gradient magnetic field, and becomes an ECR plasma flow.

In an ECR plasma sputtering apparatus,
A cylindrical target to which a negative bias voltage is applied is provided in the middle of the ECR plasma flow. Then, ions in the ECR plasma stream are accelerated by the cylindrical target and collide with the target, thereby sputtering particles constituting the cylindrical target. Neutral particles sputtered from the cylindrical target are partially ionized in the ECR plasma flow, accelerated toward the substrate together with the ECR plasma flow, and formed on the substrate.

The ECR plasma sputtering apparatus operates as described above and is an apparatus for forming a sputter film on a substrate by a so-called ECR plasma sputtering method. The ECR plasma sputtering method is characterized in that a high-quality thin film can be easily produced while keeping the substrate at a low temperature, as compared with other various sputtering methods.

The details of the operation and characteristics of the ECR plasma sputtering apparatus are described in "Matsuoka and Ono, Applied Physics Vol. 57, No. 9 (1998), p. 1301".

[0008]

The conventional EC
The R plasma sputtering apparatus has large components located near a cylindrical target, such as a microwave waveguide for introducing a microwave into a plasma chamber, an electromagnetic coil for applying a magnetic field to the plasma chamber, and the like, and the scale of the apparatus is large. . Therefore, E
The CR plasma sputtering apparatus has a large-scale apparatus configuration when a cylindrical target is formed of a plurality of target materials to achieve multi-targeting, as is practically used in various other sputtering apparatuses. There was a problem.

In order to solve this problem, an ECR plasma sputtering apparatus is disclosed, for example, in Japanese Patent Laid-Open No. 6-2003.
As described in Japanese Patent No. 73, “Thin Film Forming Method and ECR Sputtering Apparatus”, a first target and a second target are provided side by side at the outlet of a plasma chamber, and the power applied to each target is adjusted. There is an apparatus which aims at multi-targeting.

However, in this ECR plasma sputtering apparatus, the particles constituting the first target are deposited on the target surface of the second target,
Particles constituting the target accumulate on the first target surface. Therefore, in this ECR plasma sputtering apparatus, it was difficult to form a high-purity thin film by sputtering only the first target or the second target on the substrate.

As an ECR plasma sputtering apparatus, for example, as described in JP-A-7-3446, “ECR sputtering apparatus and substrate cleaning method using ECR sputtering apparatus”, a plurality of targets can be used. There is a device provided with a shutter which can be opened and closed independently. This ECR plasma sputtering apparatus has succeeded in forming a uniform and high-purity thin film on a substrate because shutters provided on each target can be opened and closed independently.

However, in this ECR plasma sputtering apparatus, each target needs to be water-cooled, and a negative bias power supply needs to be connected to each target. Therefore, there has been a problem that the ECR plasma sputtering apparatus has a very complicated apparatus configuration as a whole.

Accordingly, the present invention provides a rotatable shield plate on the inner surface side of a cylindrical target formed by combining a plurality of target materials, so that the configuration of the apparatus is not enlarged and complicated. It is an object of the present invention to provide an electron cyclotron resonance plasma sputtering apparatus that achieves multi-targeting. It is another object of the present invention to provide a method for producing a thin film in which a plurality of target materials are selected and a sputter film is formed by using a shield plate rotatable on the inner surface side of a cylindrical target.

[0014]

In order to achieve the above-mentioned object, an electron cyclotron resonance plasma sputtering apparatus according to the present invention comprises a cylindrical target formed by combining a plurality of target materials into a cylindrical shape. A shield plate rotatable at a predetermined distance from each of the target materials, and the shield plate shields a predetermined target material among the plurality of target materials.

In the electron cyclotron resonance plasma sputtering apparatus configured as described above, by fixing the position of the rotatable shield plate on the inner surface side of the cylindrical target, a desired target among a plurality of target materials can be obtained. Only the material is formed by sputtering on the substrate.

In order to achieve the above-mentioned object, a method of manufacturing a thin film according to the present invention is characterized in that a plurality of target materials are combined in a cylindrical shape to form a cylindrical target, and the target is formed on the inner surface side of the cylindrical target. A shield plate rotatable at a predetermined distance from the material shields a predetermined target material among the plurality of target materials, and an unshielded target material among the plurality of target materials is subjected to electron cyclotron resonance plasma. By sputtering on the substrate.

In such a method for producing a thin film, the discharge of the shielded target material is automatically stopped, and the shielded target material is not sputtered. Therefore, according to such a method for producing a thin film, a desired target material is selected from a plurality of target materials and sputtered on the substrate by the shield plate rotatable on the inner surface side of the cylindrical target. Becomes easier.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. Hereinafter, an electron cyclotron resonance plasma sputtering apparatus 1 (hereinafter, referred to as an ECR plasma sputtering apparatus 1) as shown in FIG. 1 will be described.

The ECR plasma sputtering apparatus 1 has an ECR
A plasma chamber 2 for generating plasma, and a film forming chamber 4 for forming a sputter film on the substrate 3 by the ECR plasma
And In the ECR plasma sputtering apparatus 1,
The plasma chamber 2 and the film forming chamber 4 are disposed adjacent to each other and share an internal space. Further, as shown by an arrow A in FIG. 1, the gas inside the plasma chamber 2 and the film forming chamber 4 is exhausted by an exhaust device (not shown), and is kept at a high vacuum.

The plasma chamber 2 is provided with a microwave introduction window 5 and a gas introduction port 6 on one surface. Further, a microwave waveguide 7 is disposed outside the plasma chamber 2 adjacent to the microwave introduction window 5, and a gas introduction pipe 8 is connected to the gas introduction port 6. Microwaves are emitted from the microwave waveguide 7 into the sputtering chamber 2 through the microwave introduction window 5 as shown by an arrow B in FIG. As shown by an arrow C in FIG.
Discharge gas is released into the plasma chamber 2 through the gas inlet 6. In addition, a coil 9 for applying a magnetic field to the plasma chamber 2 is provided outside the plasma chamber 2. In the plasma chamber 2, ECR plasma is generated. The ECR plasma is emitted from the plasma emission port 2a toward the film forming chamber 4.

The film forming chamber 4 includes a substrate holder 10 for holding the substrate 3, a cylindrical target 11 disposed adjacent to the plasma emission port 2 a of the plasma chamber 2, a substrate holder 10 and the cylindrical target 11. Substrate shutter 1 disposed between
2 is provided.

The substrate holder 10 is disposed so as to be substantially perpendicular to the flow direction of the ECR plasma emitted from the plasma chamber 2 and holds the substrate 3 as shown by an arrow D in FIG. It can be rotated freely. Further, the substrate holder 10 is provided with a heater (not shown) for heating the substrate 3.

As shown in FIG. 2, the cylindrical target 11 has a backing plate 13 formed in a polygonal cylindrical shape.
And a backing plate 13 formed in a substantially rectangular flat plate shape.
And a plurality of target materials 14 disposed on the inner surface of the target. The cylindrical target 11 is provided on its inner surface with a plurality of shield plates 15 rotatably disposed at a predetermined distance from the target material 14.

The backing plate 13 is formed in an octagonal cylindrical shape in the illustrated example, and is formed of a conductive material such as Cu or Al. This backing plate is electrically connected to the power supply 16 shown in FIG. The tubular target 11 has a structure that allows the target material 14 to be water-cooled via the backing plate 13 (not shown).

The target material 14 is formed in a substantially rectangular flat plate shape by a material deposited on the substrate 3. Also,
The target members 14 are respectively bonded and fixed to the inner wall surface of the backing plate 13. The target material 14 is electrically connected to the backing plate 13 and is thereby electrically connected to the power supply 16. The target material 14 is disposed such that the inner surface side of the tubular target 11 is a target surface 14 a and the target surface 14 a is substantially perpendicular to the substrate 3.

In the example shown in FIG. 2, the ECR plasma sputtering apparatus 1 is provided with four types of two target materials 14 each formed of a different material. These target materials 14 are fixed to the inner wall surface of the cylindrical target 11 such that the matching target materials 14 are of different types. In addition, the ECR plasma sputtering apparatus 1 has a structure shown in FIG.
Although not shown in the figure, a donut-shaped shield plate is provided to prevent the front and rear end surfaces of the target material 14 from being sputtered.

The shield plate 15 is formed of a conductive material such as Cu, for example, in a substantially rectangular flat plate shape, and is disposed so as to be rotatable at a predetermined distance from the target material 14. Specifically, for example, a large-diameter ball bearing 17 is disposed inside the film forming chamber 4 so as to be aligned with the cylindrical target 11. The large-diameter ball bearing 17
The outer ring is fixed to the inner wall surface of the film forming chamber 4, and the inner ring is rotatable. The shield plate 15 is rotatable at a predetermined distance from the target member 14 by being fixed to the inner ring of the large-diameter ball bearing 17 via a support member 18.

In the ECR plasma sputtering apparatus 1, a rotating means 19 such as a motor is provided inside the film forming chamber 4, and the rotating force of the rotating means 19 is largely transmitted by a transmitting means 20 such as a chain belt. It is transmitted to the inner ring of the bore ball bearing 17. That is, the shield plate 15 is freely rotated and driven by the rotating means 19.

The shield plate 15 is made of the target material 1
4 is formed large enough to cover one of them and is electrically grounded. This allows the shield plate 15 to shield one of the target materials 14 and prevent the target material 14 from being sputtered by ECR plasma.

In the example shown in FIG. 2, four shield plates 15 are provided for the large-diameter ball bearings 17, each of which is arranged at an angular interval of 90 °.

In the ECR plasma sputtering apparatus 1, if the size of the shield plate 15 is too small, it becomes difficult to completely shield the target material 14.
Further, in the ECR plasma sputtering apparatus 1, if the size of the shield plate 15 is too large, the target material 14 adjacent to the target material 14 to be shielded is also covered, so that the sputtering efficiency is reduced. Therefore,
It is desirable that the size of the shield plate 15 be determined in consideration of sufficiently covering one of the target materials 14 and the sputtering efficiency.

Further, it is desirable that the shield plate 15 is formed to be curved along the inner peripheral surface of the cylindrical target 11. Thereby, when the shield plate 15 rotates on the inner peripheral side of the cylindrical target 11, the distance from the target material 14 can be kept substantially constant.

The distance at which the shield plate 15 is separated from the target material 14 (hereinafter referred to as a separation distance) may be determined based on Paschen's law so as not to cause discharge. desirable. Specifically, for example, the term of the product of the pressure and the separation distance in the relational expression based on Paschen's law is determined to be a small value.
The separation distance of the shield plate 15 is determined by the size and material of the shield plate 15 with respect to the target material 14, the pressure inside the film forming chamber 4, and the like, and is, for example, 1 to 4 mm. In the ECR plasma sputtering apparatus 1, when the separation distance is, for example, 4 mm or more, the shield plate 15
Therefore, it is important that the separation distance be equal to or less than a predetermined value because a discharge may occur between the shield member 15 and the target material 14 shielded by the shield plate 15.

The substrate shutter 12 is formed, for example, of a conductive material such as Cu into a flat plate large enough to shield the substrate 3 held by the substrate holder 10. The substrate shutter 12 is located between the tubular target 11 and the substrate 3, and is rotatably disposed as shown by an arrow E in FIG.

The substrate shutter 12 is fixed at a position where the substrate 3 is completely shielded when sputtering film formation is not performed on the substrate 3, so that a so-called closed state is established. Further, the substrate shutter 12 is rotated from the closed state to completely open the space between the cylindrical target 11 and the substrate 3 when performing sputter deposition on the substrate 3, and is in a so-called open state.

The first power supply 16 has a frequency of 13.56 M
It is a high frequency power supply of about Hz, and is electrically connected to each target material 14 of the cylindrical target 11. The first power supply 16 applies a high frequency to the target materials 14 to apply a negative bias voltage to the target materials 14. This allows the ECR plasma to collide with the target surface 14a of the target material 14 and emit target particles.

The ECR plasma sputtering apparatus 1 configured as described above operates as described below to form a thin film on the substrate 3.

First, the substrate 3 is mounted on the substrate holder 10,
The substrate holder 10 faces the plasma emission port 2a. Then, the gas inside the plasma chamber 2 and the film forming chamber 4 is evacuated by an exhaust device, and evacuation is performed until a sufficiently high vacuum is obtained.

Next, the substrate 3 is heated by a heater provided in the substrate holder 10, and the substrate holder 10 is rotated as shown by an arrow D in FIG. The first power supply 16 applies a predetermined voltage to the cylindrical target 11, supplies a current to the coil 9, and applies a magnetic field to the plasma chamber 2.

Next, as shown by an arrow B in FIG. 1, microwaves are emitted from the microwave waveguide 7 to the sputtering chamber 2 through the microwave introduction window 5, and as shown by an arrow C in FIG. The discharge gas is discharged from the gas introduction pipe 8 to the plasma chamber 2 through the gas introduction port 6 and the internal pressure is 1 mTorr.
r. As a result, ECR plasma is generated inside the plasma chamber 2, and the ECR plasma is emitted from the plasma emission port 2 a toward the film formation chamber 4. Then, as shown by an arrow E in FIG. 1, the substrate shutter 12 is rotated and opened.

The ECR plasma released into the film forming chamber 4 is
The inner surface side of the cylindrical target 11, that is, the target material 1
No. 4 target surface 14a is sputtered, and target material 1
The particles constituting 4 are repelled toward the substrate 3. E
Target material 14 repelled by CR plasma
Are accelerated toward the substrate 3 together with the ECR plasma flow, and a film is formed on the substrate 3.

As described above, the ECR plasma sputtering apparatus 1 is rotatable on the inner surface side of the cylindrical target 11 formed by combining a plurality of target materials 14 while maintaining a predetermined distance from these target materials 14. The shield plate 15 is provided. Therefore, in the ECR plasma sputtering apparatus 1, each target material 14 is formed of a different material,
Is shielded by the shield plate 15, the target material 14 to be sputtered can be selected.

That is, the ECR plasma sputtering apparatus 1
In the method described above, a thin film made of a different material is formed on the substrate 3 by forming each target material 14 with a different material and rotating the shield plate 15 to select a target material 14 to be sputtered. Can be. Therefore, the ECR plasma sputtering apparatus 1
The target material 14 to be sputtered can be easily selected without requiring a complicated apparatus configuration such as a conventional multi-target type ECR plasma sputtering apparatus.

In the ECR plasma sputtering apparatus 1, a plurality of target materials 14 formed of different materials are formed by rotating the shield plate 15 while performing sputtering film formation on the substrate 3 with the substrate shutter 12 opened. In order to be exposed to the ECR plasma, a thin film in which a plurality of materials are mixed can be formed on the substrate 3 by sputtering. That is, the ECR plasma sputtering apparatus 1
Is the shield plate 1 with the substrate shutter 12 open.
5, a plurality of thin films made of different materials are continuously formed for a predetermined period of time by rotating 5, and a composite thin film is formed on the substrate 3 with a high purity based on the stoichiometric composition. Can be.

Further, the ECR plasma sputtering apparatus 1
After a predetermined target material 14 is shielded and a sputter film is formed on the substrate 3, the substrate shutter 12 is closed and the shield plate 15 is rotated to completely shield the shield plate 15 from another target material 14. After stopping at the position, the substrate shutter 12 may be opened. In this case, the ECR plasma sputtering apparatus 1 can stack and form various types of thin films on the substrate 3, and can steeply form an interface between the thin films. That is, the ECR plasma sputtering apparatus 1 can form a high-purity thin film such as a superlattice film or a composition modulation film including a gradient material film on the substrate 3 by stacking.

The ECR plasma sputtering apparatus 1
In the example shown in FIG. 2, the cylindrical target 11 is formed in an octagonal cylindrical shape, and a substantially rectangular flat target material 14 is fixed to each inner wall surface of the cylindrical target 11, and the four shield plates 15 are large-diameter balls. Although the bearings 17 are arranged at angular intervals of 90 °, the present invention is not limited to such a configuration. In the ECR plasma sputtering apparatus 1,
The area to be shielded by the shield plate 15 or the cylindrical target 11
The number provided for is not limited.

The ECR plasma sputtering apparatus 1 may have, for example, a cylindrical target 11 and a plurality of target materials 14 curved along the inner wall surface of the cylindrical target 11. The ECR plasma sputtering apparatus 1 forms an ECR plasma by forming the cylindrical target 11 so as to have a substantially cylindrical shape when the material used for the target material 14 is a material such as a metal material that can be easily formed. The area of the exposed target material 14 can be increased, and the sputtering can be performed without bias, so that the sputtering efficiency can be improved.

On the other hand, in the ECR plasma sputtering apparatus 1, when the cylindrical targets 11 are formed by combining substantially flat target materials 14, a gap is generated at a side end portion where these target materials 14 are adjacent to each other. . However, in the ECR plasma sputtering apparatus 1, the size of the shield plate 15 is set to be slightly larger than the size of the target material 14, and the side edge of the target material 14 adjacent to the target material 14 to be shielded is also slightly shielded. The target material 1 having a substantially flat plate shape
Even when using No. 4, it is possible to prevent substances other than the target material 14 to be sputtered from being sputtered from the gap at the side end.

That is, the ECR plasma sputtering apparatus 1
Can be used as the target material 14 even if a material having a complicated shape is difficult to produce, such as a sintered body such as an oxide or a single crystal material, and an impurity is formed on the substrate 3 by sputtering. A high-purity thin film can be formed without being performed. Specifically, for example, In-Ga
-When manufacturing a nitride semiconductor element of a 3B group element such as Al-N or the like, the target material is processed into a cylindrical shape, or a side end of the target material is cut into a trapezoidal shape. On the other hand, there is no need to perform complicated shape processing. Therefore, the ECR plasma sputtering apparatus 1
Sputter film formation can be easily performed regardless of the material to be sputtered.

Also, the ECR plasma sputtering apparatus 1
In the above description, two types of target materials 14 are provided four each, and the same type of target materials 14 are disposed to face each other. However, the type and number of target materials 14 are not limited. The ECR plasma sputtering apparatus 1 may be provided on a cylindrical target 11 having, for example, three types of target materials 14 each having two hexagonal cylinders. 12 for each
It may be provided on a cylindrical target 11 formed in a rectangular cylindrical shape.

At this time, the ECR plasma sputtering apparatus 1
, The number of shield plates 15 covering the same kind of target materials 14 is provided, respectively.
It is desirable to arrange them at an angular interval that can cover all at once. Thereby, the ECR plasma sputtering apparatus 1
Can prevent a material other than the target material 14 to be sputtered from being formed on the substrate 3 as an impurity.

Also, the ECR plasma sputtering apparatus 1
Although the target materials 14 of the same kind are arranged facing each other, they may be arranged without facing each other. Where E
In the CR plasma sputtering apparatus 1, since the sputtered target particles are emitted most in the direction perpendicular to the target surface 14a, by disposing the same type of target materials 14 facing each other, the different types of target material elements can be used. Mixing can be prevented, and the utilization efficiency of the target material can be improved.

In the ECR plasma sputtering apparatus 1, a slight pre-sputtering may be performed on the target material 14 to be sputtered with the substrate shutter 12 closed. Thereby, the ECR plasma sputtering apparatus 1 can remove in advance the deposits and the like on the target surface 14a of the target material 14, and can form a thin film with higher purity on the substrate 3.

In the ECR plasma sputtering apparatus 1, the substrate shutter 12 is closed, the shield plate 15 is rotated, and the substrate shutter 12 is not opened immediately after the shield plate 15 is positioned and fixed. It is desirable that the substrate shutter 12 be closed. In the ECR plasma sputtering apparatus 1, by opening the substrate shutter 12 after the ECR plasma is in a stable state, a higher quality thin film can be formed on the substrate 3 and the target material 14 can be formed. Of the target surface 14a can be pre-sputtered.

[0055]

Hereinafter, embodiments of the present invention will be described.
It goes without saying that the present invention is not limited to the embodiments described below. Hereinafter, an embodiment in which an SiO ₂ thin film and a TiO ₂ thin film are stacked and formed on a substrate 3 using the above-described ECR plasma sputtering apparatus 1 will be described.

First, the target material 14 is 40 m long.
A substantially rectangular flat plate-shaped SiO ₂ quartz plate having dimensions of m, 38 mm in width and 4 mm in thickness and four TiO ₂ sintered bodies were prepared. The SiO ₂ quartz plate and the TiO ₂ sintered body were fixed to the inner wall surface of the octagonal cylindrical target 11 via indium via a copper backing plate 13. At this time, the SiO ₂ quartz plate and T
The iO ₂ sintered body was fixed to the inner wall surface of the tubular target 11 such that the same type was opposed to each other and the adjacent type was different.

Next, as the shield plate 15, a thickness of 1 m
Four curved rectangular flat-plate shield plates 15 each having a dimension of m, a length of 40 mm, a radius of curvature of 46 mm, a sector angle of 50 °, and made of stainless steel (SUS304) were prepared. Then, each of these shield plates 15 is
Large-diameter ball bearing 17 via support member 18 at an angular interval of ゜
Fixed to the inner ring. Further, each shield plate 15 was fixed to the large-diameter ball bearing 17 by adjusting the height of the support member 18 so as to be rotatable while keeping an interval of 2 mm to 3 mm from the target material 14.

As the large-diameter ball bearing 17, a bearing (call number 6921) manufactured by Koyo Seiko was used. After the large-diameter ball bearing 17 is sufficiently washed with acetone,
It was provided in the film forming chamber 4. As the rotating means 19 for rotating and driving the shield plate 15, a high vacuum stepping motor (B14.1) manufactured by MDC was used. Further, the substrate shutter 12 is configured to be rotated using a rotation introducing machine that operates by compressed air, and the rotation is controlled by controlling the compressed air sent to the rotation introducing machine by an electromagnetic valve.

Next, a substrate 3 made of quartz, which is an object on which a film is to be formed, is formed.
Was prepared and fixed to the substrate holder 10. At this time, the distance between the substrate holder 10 and the cylindrical target 11 is 120 m.
m. Then, the plasma chamber 2 and the film formation chamber 4 are evacuated by a turbo molecular pump, and 6 × 10 ⁻⁸
Vacuum was applied to Torr. Further, the substrate holder 10 to which the substrate 3 was fixed was rotated at a constant speed as shown by an arrow D in FIG. 1, and the substrate 3 was heated to 150 ° C. by a heater provided in the substrate holder 10.

In the following, first, the plate shutter 12 is
And the cylindrical target 11 was stopped in a closed state, and pre-sputtering was performed on each target material 14.

In the pre-sputtering step, power is supplied to the coil 9 to generate a magnetic field, and this magnetic field is applied to the plasma chamber 2 and the microwave waveguide 7
From the microwave to the sputtering chamber 2. In addition, Ar gas was discharged as a discharge gas from the gas inlet tube 8 at a flow rate of 30 sccm, and O ₂ gas was discharged into the plasma chamber 2 at a flow rate of 10 sccm. As a result, ECR plasma is generated in the plasma chamber 2, and the ECR plasma is emitted toward the film formation chamber 4. Further, the plasma chamber 2 and the film formation chamber 4 are maintained at a pressure of 1 mTorr because the discharge gas discharged from the gas introduction pipe 8 is exhausted by the turbo molecular pump. Further, 400 W of high frequency power was supplied to each target material 14 from the power supply 16 via the cylindrical target 11.

The EC released from the plasma chamber 2
The R plasma was caused to collide with the target surface 14a of the target material 14 provided at the plasma emission port 2a, thereby removing deposits on the target surface 14a.

Next, the substrate shutter 12 was opened, and the main sputtering was performed on the substrate 3 in the same manner as in the pre-sputtering step described above.

In this main sputtering step, first, T
A shield plate 15 was fixed at a position where the target material 14 formed of the iO ₂ sintered body was shielded. Then, the ECR plasma emitted from the plasma chamber 2 was caused to collide with a target surface 14a of a target material 14 formed of a SiO ₂ quartz plate, thereby emitting target particles. The target particles accelerated toward the substrate 3 together with the ECR plasma flow, and were deposited on the substrate 3. Thus, a SiO ₂ thin film was formed on the substrate 3.

Next, the substrate shutter 12 was closed, the shield plate 15 was rotated, and the shield plate 15 was fixed at a position for shielding the target material 14 formed of a SiO ₂ quartz plate. Then, the substrate shutter 12 was opened, and a TiO ₂ thin film was further formed on the SiO ₂ thin film formed on the substrate 3 by ECR plasma.

Observation of the thin film produced as described above confirmed that the interface between the SiO ₂ thin film and the TiO ₂ thin film was sufficiently clear and steep. In addition, it was confirmed that a high-quality multilayer film could be easily formed on the substrate 3 by repeating the above procedure and rotating the shield plate 15 in order. Therefore, according to the method for manufacturing a thin film according to the present invention, it is understood that a high-quality thin film can be easily formed on a substrate using a plurality of target materials made of different materials.

[0067]

As described above, in the electron cyclotron resonance plasma sputtering apparatus according to the present invention, a predetermined target material can be shielded by the shield plate rotatable on the inner surface side of the cylindrical target. Thus, the electron cyclotron resonance plasma sputtering apparatus can perform sputtering film formation by selecting a plurality of target materials without increasing the size and complexity of the apparatus configuration.

Further, according to the method of manufacturing a thin film according to the present invention, since the shield plate is rotatable on the inner surface side of the cylindrical target, it is possible to easily shield a predetermined target material. Therefore, the thin film manufacturing method can form a uniform and high-purity thin film on a substrate by appropriately controlling the rotation of the shield plate, and can form a multilayer thin film having a steep interface or a gradient material thin film. Can easily be formed on a substrate with high quality.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an ECR plasma sputtering apparatus according to the present invention.

FIG. 2 is a schematic view showing a state where a cylindrical target of the apparatus is viewed from a substrate side.

[Explanation of symbols]

1 ECR plasma sputtering device, 2 plasma chamber, 3
Substrate, 4 deposition chamber, 9 coil, 10 substrate holder,
11 cylindrical target, 12 substrate shutter, 14 target material, 15 shield plate, 17 large diameter ball bearing

Claims (4)

[Claims] An inner surface of a cylindrical target formed by combining a plurality of target materials into a cylindrical shape, a shield plate rotatable at a predetermined distance from each of the target materials, Is an electron cyclotron resonance plasma sputtering apparatus, wherein a predetermined target material is shielded from the plurality of target materials. 2. A substrate shutter disposed between the cylindrical target and a substrate to be sputtered so as to be openable and closable, the substrate shutter shielding the substrate when the shield plate rotates. The electron cyclotron resonance plasma sputtering apparatus according to claim 1, wherein 3. A method comprising combining a plurality of target materials into a cylindrical shape to form a cylindrical target, and a shield plate rotatable at a predetermined distance from each of the target materials on an inner surface of the cylindrical target. A method of manufacturing a thin film, wherein a predetermined target material is shielded among the target materials, and an unshielded target material among the plurality of target materials is sputtered on the substrate by electron cyclotron resonance plasma. 4. When the shield plate rotates, the substrate is shielded by a substrate shutter that is openably and closably disposed between the tubular target and the substrate. 4. The method for producing a thin film according to 3.