KR101838852B1 - Sputtering equipment - Google Patents

Abstract

Disclosed is a sputtering device. The disclosed sputtering device comprises: a chamber which has a vacuum; a gas supplying unit which supplies gases to the inside of the chamber; a substrate support unit which is coupled to one side of the chamber to support a substrate which is a target for a thin film disposition; a target fixing unit which fixes a target placed to face the substrate; a power supplying unit which supplies bias voltage to the target to form plasma; and a magnet unit which is placed away from the target at a predetermined distance, and applies magnetic field to the target. The magnet unit comprises: a first magnet of which an upper part has an N pole or an S pole and a lower part has a pole opposite to the upper part, along the longitudinal direction; a second magnet which is parallel to and placed away from the first magnet at a predetermined distance, and of which an upper part has a pole opposite to the upper part of the first magnet and a lower part has a pole opposite to the lower part of the first magnet; and a magnet rotating unit which rotates the first and second magnets. The plasma of gases injected when a voltage is applied to the target generates sputtering on a surface of the target by means of a magnetic field formed by the first and second magnets, between the first and second magnets to be parallel with the first and second magnets. The first and second magnets are rotated by the magnet rotating unit, and the sputtering is generated uniformly across the overall area of the target. The present invention is able to form a thin film with a uniform thickness on a substrate.

Description

[0001] Sputtering equipment [0002]

More particularly, the present invention relates to a sputtering apparatus, and more particularly, to a sputtering apparatus in which magnets having polarities different from each other formed at upper and lower portions in the longitudinal direction are spaced apart from each other by a predetermined distance, And the thickness of the thin film deposited on the substrate is uniformly formed by making the thickness of the magnet thinner than the edge of the center in the longitudinal direction.

The PVD (Physical Vapor Deposition) method for depositing a thin film in a semiconductor device fabrication process is a method of depositing particles of the same material (Al, Ti, TiW, W, Ti, TiN, , Which is a method of forming a metal film or an alloy film.

This physical vapor deposition method can roughly be divided into a sputtering method and an evaporation method. Here, the evaporation method is a method of heating a solid or a liquid to decompose into molecules or atoms and then condensing on the surface of the substrate.

The sputtering method is a method of colliding high energy particles with a target made of a deposition target material and depositing the released material on the substrate. Such a sputtering method can form a thin film over a wide area, and when forming an alloy thin film, adjustment of the composition ratio thereof is easier than other vapor deposition methods. Therefore, it is widely used in the manufacturing process of semiconductor devices (DRAM, SRAM, NVM, LOGIC, etc.) and other electronic devices.

As the sputtering method, the sputtering method and the magnetron sputtering method are widely used. The RF sputtering method using a radio frequency (RF) or direct current (DC) method has a disadvantage in that the structure is simple, but the film formation rate is slow and the temperature rises due to collision of high energy particles with the substrate, and film damage or composition separation occurs.

The magnetron sputtering method is a sputtering method which is developed to solve such a disadvantage. In the magnetron sputtering method, a magnetic field parallel to the target surface is applied to confine electrons in the vicinity of the target, thereby generating a high-density plasma.

The magnetron sputtering method can perform film deposition at a high speed and can suppress the temperature rise of the substrate by controlling the secondary electrons. In addition, the magnetron sputtering method can use a magnetic field, so that the process conditions inside the reactor can be adjusted to a low-pressure and high-density plasma environment to enhance the directivity of the sputtering particles. As a result, the stepped portion can effectively deposit the sputtering particles, thereby improving the step coverage.

A conventional general magnetron sputtering apparatus has a substrate support for seating a substrate inside a vacuum chamber, and a target is located opposite the substrate support. In a magnetron sputtering apparatus, a plurality of magnets are arranged on a rotating plate located at the rear of the target to form magnetic force lines in a certain direction. In addition, a power supply unit is provided outside the chamber so that a voltage can be applied to the electrode provided with the target in the process.

When a certain degree of vacuum is maintained in the chamber, a vacuum gas such as argon is drawn into the chamber, and discharge is caused by the negative voltage applied to the electrode. Thus, a plasma composed of ionized gas molecules, neutral molecules and electrons is formed by electric discharge, and the gas molecules are accelerated by the negative voltage and collide with the target. The atoms of the target surface are subjected to kinetic energy by collision and released from the target, and these atoms are deposited in the form of a thin film on the substrate. At this time, the thickness of the deposited thin film is determined by the applied voltage, the degree of vacuum, the deposition time, and the like.

However, in the conventional magnetron sputtering apparatus, sputtering occurs locally on the surface of the target, and the total area of the target can not be used.

On the other hand, in the conventional magnetron sputtering apparatus, the thickness of the thin film on the substrate deposited by sputtering is uneven, resulting in fluctuation of the device performance, which causes the reliability of the product to deteriorate.

Accordingly, it is urgently required to develop a sputtering apparatus capable of increasing the utilization rate of a target and forming a uniform thin film on a substrate.

Korean Patent Laid-Open Publication No. 2011-0065353

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sputtering apparatus which increases sputtering uniformly over a whole surface of a target to increase the target utilization rate.

Another object of the present invention is to provide a sputtering apparatus capable of forming a thin film having a uniform thickness on a substrate.

Another object of the present invention is to increase the production efficiency of a magnet having a variable thickness by continuously attaching a plurality of rectangular parallelepiped magnets.

The present invention relates to a vacuum chamber, A gas supply unit for supplying gas into the chamber; A substrate support coupled to one side of the chamber to support a substrate on which a thin film is to be deposited; A target fixing unit for fixing a target disposed opposite to the substrate; A power supply for supplying a bias voltage to the target to form a plasma; And a magnet unit arranged to be spaced apart from the target by a predetermined distance and applying a magnetic field to the target, wherein the magnet unit is linearly formed in a longitudinal direction, and an N pole or an S pole A first magnet having an opposite polarity to the upper portion; And a pole opposite to the upper portion of the first magnet is formed on the upper portion and a pole opposite to the lower portion of the first magnet is formed on the lower portion. A second magnet formed on the first magnet; Wherein the first magnet and the second magnet have a width and a height that are perpendicular to the longitudinal direction of the first magnet and the second magnet, Wherein the magnet and the second magnet are shorter than the length of the magnet, and the target fixing portion is supported and coupled to the magnet unit by a bearing,
Wherein a plasma of the injected gas when a voltage is applied to the target is applied between the first magnet and the second magnet on the surface of the target by a magnetic field formed by the first magnet and the second magnet, Wherein the first magnet and the second magnet are rotated by the magnet rotating portion so that the sputtering occurs uniformly over the entire area of the target. A sputtering apparatus is provided.

The magnet unit of the present invention may further include a magnet supporting block coupled to the magnet rotating portion and having two insertion grooves into which the first magnet and the second magnet are inserted, respectively.

The magnet rotating portion of the present invention may further include: a motor for providing a rotating force for rotating the magnet; A coupling for coupling the rotation axis of the motor to the yoke rotation axis; A yoke rotating shaft coupled to the coupling and transmitting rotational force of the motor to the yoke; And a yoke supporting and rotating the first and second magnets.

The thickness of the first magnet and the second magnet of the present invention is characterized in that the central portion in the longitudinal direction is thinner than the edge.

The first magnet and the second magnet of the present invention are characterized in that the thickness is symmetrically changed with respect to the center in the longitudinal direction.

Further, the first magnet and the second magnet of the present invention are integrally formed.

Further, in the present invention, each of the first magnet and the second magnet is formed by stacking a plurality of magnets and adhering to each other.

The sputtering apparatus according to the present invention has the effect of increasing the target utilization rate by causing the sputtering uniformly over the entire surface of the target.

Further, the sputtering apparatus according to the present invention has an effect of forming a thin film on a substrate to have a uniform thickness.

Further, the present invention has an effect of increasing the production efficiency of a magnet having a variable thickness.

The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

1 is a conceptual view of a sputtering apparatus according to the present invention.
2 is a cross-sectional view of a cathode according to the present invention.
3 is an exploded view of a magnet and a magnet supporting block according to the present invention.
4 is a view for explaining the principle of sputtering on a target according to the present invention.
5 is a cross-sectional view of a magnet according to the present invention.
6 is a view for explaining the principle of deposition of a target material on a substrate.
Fig. 7 shows a modification of the magnet according to the present invention.

Hereinafter, various embodiments of the present document will be described with reference to the accompanying drawings. It should be understood, however, that the techniques described herein are not intended to be limited to any particular embodiment, but rather include various modifications, equivalents, and / or alternatives of the embodiments of this document. In connection with the description of the drawings, like reference numerals may be used for similar components.

Also, the terms "first," "second," and the like used in the present document can be used to denote various components in any order and / or importance, and to distinguish one component from another But is not limited to those components. For example, 'first part' and 'second part' may represent different parts, regardless of order or importance. For example, without departing from the scope of the rights described in this document, the first component can be named as the second component, and similarly the second component can also be named as the first component.

It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the other embodiments. The singular expressions may include plural expressions unless the context clearly dictates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the art. The general predefined terms used in this document may be interpreted in the same or similar sense as the contextual meanings of the related art and, unless expressly defined in this document, include ideally or excessively formal meanings . In some cases, even the terms defined in this document can not be construed as excluding the embodiments of this document.

1 is a conceptual view of a sputtering apparatus according to the present invention.

Will be described with reference to Fig.

The sputtering apparatus according to the present invention includes a chamber 100, a gas supply unit 200, a substrate support unit 300, a target fixing unit 400, a power supply unit 500, and a magnet unit 600.

The chamber 100 is kept in vacuum as a space where sputtering and thin film deposition take place.

The gas supply unit 200 supplies gas into the chamber 100. Arsenic (Ar), which is a chemically inert gas, is commonly used as a gas to be introduced into the chamber 100.

The substrate support 300 supports a substrate to which a thin film is to be deposited. The substrate support 300 is coupled to one side of the chamber 100 and is typically mounted at the top or bottom of the chamber 100. The sputtering apparatus according to the present invention has a structure in which the substrate is disposed on the upper side and the target T is disposed on the lower side.

A target fixing portion 400 is provided to support a target T made of a deposition material.

The target fixing portion 400 is also disposed so as to face the substrate M so that the target T is arranged to face the substrate M. [

The target T and the target fixing portion 400 are fixed, unlike the magnet unit 600 which will be described later.
The target fixing portion 400 is supported on the magnet unit 600 by a bearing B. Therefore, even when the magnet unit 600 rotates, the target fixing portion 400 can be kept stationary.

In the case of FIG. 1, the two targets T are inclined and opposed to the substrate M, but they may be disposed vertically below the substrate M when the target T is one. Arranging the target T so as to face the substrate M is intended to increase the amount of the target (T) material detached from the target T deposited on the substrate M.

The power supply unit 500 supplies a bias voltage to the target T so that the gas injected into the chamber 100 forms a plasma.

The magnet unit 600 is disposed at a predetermined distance from the target T. The magnet unit 600 forms a magnetic field around the target T to confine electrons and ions in front of the target T. [

When argon (Ar), which is a chemically inert gas, flows into the chamber 100, argon is plasmaized by applying an appropriate voltage to the target T, and positive ionized argon ions are applied to the negatively charged target T, The target (T) atoms or atomic clusters are sputtered from the target (T) by momentum transfer.

The cathode is a term encompassing the target (T), the target fixing portion (400), and the magnet unit (600).

FIG. 2 is a sectional view of a cathode according to the present invention, and FIG. 3 is an exploded view of a magnet and a magnet supporting block according to the present invention.

The structure of the magnet unit 600 will be described in detail with reference to FIGS. 2 and 3. FIG.

The magnet unit 600 includes a first magnet 610, a second magnet 620, a magnet support block 630, and a magnet rotation unit 700.

A magnet support block 630 is provided to support the first magnet 610 and the second magnet 620.

The magnet supporting block 630 is bolted to the upper portion of the magnet rotating portion 700. Two insertion grooves 640 are formed in the magnet supporting block 630 and the first magnet 610 and the second magnet 620 are inserted into the insertion groove 640, respectively.

The magnet is supported by the magnet supporting block 630 without directly coupling the first magnet 610 and the second magnet 620 to the magnet rotating portion 700. This is because when the magnet is directly coupled to the magnet rotating portion 700 The purpose of the present invention is to prevent the problem that the magnets are weakened in strength due to the formation of holes in the magnets, and to prevent the danger of magnet scattering by covering the entire surface of the rotating magnet.

The first magnet 610 is formed with an N pole or an S pole at an upper portion thereof along the longitudinal direction of the magnet and a pole opposite to the upper portion at a lower portion thereof.

The second magnet 620 is disposed in parallel with the first magnet 610 by a predetermined distance. A pole opposite to the upper portion of the first magnet 610 is formed on the upper portion of the second magnet 620 and a pole opposite to the lower portion of the first magnet 610 is formed on the lower portion.

The first magnet 610 and the second magnet 620 arranged in the above-described structure are rotated by the magnet rotating portion 700.

The magnet rotating portion 700 includes a motor 740, a coupling 730, a yoke rotating shaft 720, and a yoke 710.

The motor 740 provides a rotational force to rotate the magnet.

The coupling 730 couples the rotation axis of the motor 740 to the yoke rotation axis 720.

The yoke rotating shaft 720 is coupled to the coupling 730 to transmit the rotational force of the motor 740 to the yoke 710.

The yoke 710 supports and rotates the first magnet 610 and the second magnet 620.

This magnet rotating portion 700 enables sputtering over the entire area of the target T. [

4 is a view for explaining the principle of sputtering in the target T according to the present invention.

Will be described with reference to FIG.

Since the magnetic line of force is formed from the N pole to the S pole, the largest magnetic force is generated between the two magnets arranged as shown in FIG. 4 in parallel with the longitudinal direction of the magnet. Therefore, positive ionized argon ions located on the target T collide against the negatively charged target T, and sputtering occurs between the two magnets in parallel with the longitudinal direction of the magnet.

However, since the magnet is rotated by the magnet rotating portion 700, the sputtering is uniformly generated over the entire area of the magnet. The sputtering apparatus according to the present invention solves the problems of the prior art in which the sputtering is locally generated in the target T and the target T utilization rate is lowered so that the utilization rate of the target T can be improved.

Fig. 5 is a cross-sectional view of a magnet according to the present invention, and Fig. 6 is a view for explaining the principle of deposition of a target (T) material on a substrate M. Fig.

Will be described with reference to Figs. 5 and 6. Fig.

In the magnet according to the present invention, both the first magnet 610 and the second magnet 620 are formed such that the thickness thereof is thinner at the center in the longitudinal direction of the magnet than at the edge. The thickness of the magnet is formed such that its center portion is the thinnest, and gradually increases toward the edge.

This is for uniformly depositing the thin film on the substrate M.

FIG. 6 (a) is a view showing a conventional magnet having a constant thickness, and FIG. 6 (b) is a view showing a magnet according to the present invention in which the thickness gradually changes in the longitudinal direction.

Each of the particles of the target T material sputtered at the target T by the magnetic field of the magnet is accelerated toward the substrate M in the radial direction so that the reaching distance to the substrate M in the vertical direction of the target T And the distance to the edge of the substrate (M) is long.

Therefore, the thickness of the thin film deposited on the substrate M becomes thick at the center portion of the substrate M, and the edge of the substrate M becomes thin.

Accordingly, in the present invention, the thickness of the magnet is thinned at the center along the magnet length direction, and thick at the edge. As shown in FIG. 6 (b), in the case of the magnet according to the present invention, a thin film having a uniform thickness can be deposited on the substrate M by varying the thickness in the longitudinal direction.

Next, a method of manufacturing the variable-thickness magnet according to the present invention will be described.

In manufacturing the thickness variable magnet, it may be integrally formed as shown in Fig. 6 (b).

The shapes of the target T and the substrate M are generally formed into a disk shape and the first magnet 610 and the second magnet 620 are arranged in the longitudinal direction with respect to the center in consideration of the balancing problem of the rotation of the magnet So that the thickness is changed symmetrically.

Fig. 7 shows a modification of the magnet according to the present invention.

As shown in FIG. 7, the variable thickness magnet can be manufactured by various methods.

Fig. 7 (a) shows that a plurality of rectangular parallelepiped magnets can be produced only through a bonding process without passing through various processing steps by continuously attaching magnets having different heights to each other.

7 (b), magnets of the same length may be stacked and bonded as a block to form a variable-thickness magnet. In this case, the manufacturing process can be further simplified by using magnets of the same length.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the invention as defined by the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Chamber 100
The gas supply part 200
The substrate support 300
The target fixing portion 400
Power supply 500
The magnet unit 600
The first magnet 610
The second magnet 620
The support block 630
Insertion groove 640
The magnet rotating part 700
York 710
Yoke rotating shaft 720
Coupling 730
Motor 740
Target T
Substrate M
Thin film P
Bearing B

Claims (7)

A chamber in which a vacuum is formed;
A gas supply unit for supplying gas into the chamber;
A substrate support coupled to one side of the chamber to support a substrate on which a thin film is to be deposited;
A target fixing unit for fixing a target disposed opposite to the substrate;
A power supply for supplying a bias voltage to the target to form a plasma; And
And a magnet unit disposed at a predetermined distance from the target and applying a magnetic field to the target,
The magnet unit includes:
A first magnet formed linearly in a longitudinal direction, an N pole or an S pole formed at an upper portion along the longitudinal direction, and a lower pole formed opposite to the upper portion;
And a pole opposite to the upper portion of the first magnet is formed on the upper portion and a pole opposite to the lower portion of the first magnet is formed on the lower portion. A second magnet formed on the first magnet;
And a magnet rotating unit for rotating the first magnet and the second magnet,
The width and height of the first magnet and the second magnet forming the cross section perpendicular to the longitudinal direction of the first magnet and the second magnet are shorter than the lengths of the first magnet and the second magnet,
Wherein the target fixing portion is coupled to the magnet unit by a bearing,
The thickness of the first magnet and the second magnet is thinner at the center in the longitudinal direction than at the edge,
Wherein a plasma of the injected gas when a voltage is applied to the target is applied between the first magnet and the second magnet on the surface of the target by a magnetic field formed by the first magnet and the second magnet, Wherein the first magnet and the second magnet are rotated by the magnet rotating portion so that the sputtering occurs uniformly over the entire area of the target. Sputtering device. The method according to claim 1,
The magnet unit includes:
And a magnet supporting block coupled to the magnet rotating portion and having two insertion grooves into which the first magnet and the second magnet are inserted, respectively. The method according to claim 1,
The magnet rotation unit includes:
A motor for providing a rotational force to rotate the magnet;
A coupling for coupling the rotation axis of the motor to the yoke rotation axis;
A yoke rotating shaft coupled to the coupling and transmitting rotational force of the motor to the yoke; And
And a yoke supporting and rotating the first and second magnets. delete The method according to claim 1,
Wherein the first magnet and the second magnet are symmetrically changed in thickness with respect to the center in the longitudinal direction. The method according to any one of claims 1 to 3,
Wherein the first magnet and the second magnet are formed integrally with each other. The method according to any one of claims 1 to 3,
Wherein each of the first magnet and the second magnet is formed by stacking a plurality of magnets and adhering to each other.

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