JPH03260067A - Sputtering device - Google Patents

Abstract

PURPOSE:To deform the surface of a target by erosion and to form a uniform thin film having invariable characteristics on plural substrates by arranging a third magnetic pole body in a specified polarity relation in addition to two magnetic pole bodies arranged on the rear of a target of a planar magnetron sputtering device. CONSTITUTION:The first pole body 2 and the second annular pole body 3 surrounding the pole body 2 and with the end face on the same side of the pole body 2 having the polarity opposite to that of the pole body 2 are arranged in the rear of the target 12 of a planar magnetron sputtering device, and the third pole body 5 is arranged in between and vertically driven by a driving motor 10 through a supporting rod 8a implanted in the supporting body 8 screwed up by a screw rod 9 rotated through worm gear reduction mechanisms 9a and 10a. The third pole body 5 is moved vertically to the surface of the target 12 and sputtering is carried out, hence the plasma on the front side of the target 12 is kept in the same state during the sputtering, and the sputtered thin film is formed on the surfaces of plural substrates from one target without any variance between the substrates and with good utilization efficiency of the target.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sputtering device used to form various thin films on a substrate, in which one end surface is close to the center of the back surface of a plate-shaped target. a first magnetic pole body facing each other; and an end face formed in an annular shape surrounding the first magnetic pole body, the end face of which is on the same side as one end face of the first magnetic pole body, is close to the peripheral edge of the back surface of the plate-shaped target. a second magnetic pole body facing opposite to each other and having a polarity opposite to one end surface of the first magnetic pole body; A planar magnetron that includes a yoke that magnetically couples the other end faces of the second magnetic pole bodies to each other, and has a sputtering cathode that forms an arc-shaped magnetic flux in an annular shape on the surface side of a plate-shaped target to form an annular plasma. The present invention relates to a sputtering apparatus of this type, and particularly to a sputtering apparatus that can efficiently form a thin film of a ferromagnetic material with little variation in characteristics of a thin film formed on a substrate from one substrate to another.

[Conventional technology]

As is well known, the sputtering cathode constituting the cathode side of this type of sputtering Wit is usually a permanent magnet with one end face facing close to the center of the back surface of the plate-shaped target 12, as shown in FIG. The first magnetic pole body 2 is
The first magnetic pole body 2 is formed in an annular shape surrounding the first magnetic pole body 2.
a second magnetic pole body 3, which is a permanent magnet, whose end face on the same side as one end face of the magnetic pole body 2 faces closely to the peripheral edge of the back surface of the plate-shaped target; It consists of a plate-shaped yoke 1 that magnetically couples the other end surfaces of the second magnetic pole bodies 2.3. And the first. The surfaces of each of the second magnetic pole bodies 2.3 facing the back surface of the target have opposite polarities, and an arc-shaped magnetic flux 4 is formed in an annular shape on the front surface side of the targeter 1-12. When a voltage is applied to the target 12 in this state, an electric field is generated between the target 12 and the anode on the back side of the substrate to be film-formed (not shown), and an electric field and a magnetic field are generated at the part where the arc-shaped magnetic flux on the surface side of the target layer 12 becomes parallel to the target surface. are orthogonal. Then, the electrons generated by this electric field perform a cycloidal interlocking movement along the annular parallel magnetic flux around this orthogonal part, ionize the sputtering gas (the atmospheric gas in which the sputtering cathode is used), and generate an annular magnetron plasma. The ions in the plasma are accelerated toward the target by an electric field, sputtering the target surface, and the subafuta particles are distributed and deposited on the surface of a substrate (not shown) facing the target to form a thin film.

[Problem to be solved by the invention]

In a sputtering cathode with such a configuration, the seed line area on the target surface expands due to sputtering, and the seed line also advances in the depth direction, changing the shape of the target surface, so that the surface of the seed line area and the magnetic pole are The distance changes from moment to moment, and the strength of the magnetic field on the surface of the seed line area changes. Due to this change, even if the power applied between the anode and cathode is the same, the reaction state in the plasma in contact with the seed line region changes and the plasma density changes over time, forming thin films on multiple substrates from one target. At the time of sputtering, variations in thin film properties occurred between the thin film formed on the substrate in the early stage of sputtering and the thin film formed on the substrate in the latter stage. Also,
The material of the target is IJ! J9! In the case of an i-type material, since a large amount of magnetic flux passes through the target in the planar direction, sufficient magnetic flux cannot be obtained on the target surface side, resulting in an extremely low sputtering efficiency.

The purpose of the present invention is to provide a sputtering method that can reduce variations in thin film properties due to changes in the shape of the target due to the seed wire, and can also form a film with high sputtering efficiency even when the target material is an S magnetic material with high magnetic permeability. The purpose is to provide equipment.

[Means to solve the problem]

In order to solve the above problems, in the present invention, a third magnetic pole body is provided between the first and second magnetic pole bodies in the conventional sputtering vtW, and the first... The polarity of each side of the second Ili polar body is the same as that of the first. The second magnetic pole bodies are disposed so as to be movable in the direction perpendicular to the target surface and to be flush with the target side end surface of each of the second magnetic pole bodies.

[Effect]

In this way, the third pole body can be replaced with the first pole body in a conventional sputtering cathode. By arranging the second magnetic pole body so as to be movable in the vertical direction, the magnetic flux emitted from the third magnetic pole body is transferred to the first magnetic pole body. It is superimposed on the magnetic flux formed on the target surface side between the second magnetic pole bodies, and the magnetic flux distribution on the target surface side changes depending on how the third magnetic pole body approaches the target.

Therefore, by changing the distance between the third magnetic pole body and the target as sputtering progresses, it is possible to suppress variations in the characteristics of the thin film formed on the substrate to be formed. Also, if the target is made of ferromagnetic material,
Bringing the third magnetic pole body closer to the target and causing the magnetic flux emitted from the third magnetic pole body to pass through the target, which has already been saturated by the magnetic flux emitted from the first and second magnetic pole bodies, and direct it toward the target surface side. This increases the magnetic flux of the scratches on the target surface and increases the sputtering efficiency.

〔Example〕

FIG. 1 shows the structure of a sputtering cathode according to an embodiment of the present invention, which includes a first magnetic pole body 2 and a second magnetic pole body formed in an annular shape surrounding the first magnetic pole body 2 and on the same side as the first magnetic pole body 2. A second magnetic pole body 3 whose end face has a polarity opposite to that of the first magnetic pole body is formed as an annular flat magnetic pole body, and a polarity of the inner surface facing the first magnetic pole body 2 is formed as an annular flat magnetic pole body. A third magnetic pole body 5 which has the same polarity as the top surface of the first magnetic pole body 2 and whose outer surface facing the second magnetic pole body 3 has the same polarity as the top surface of the second magnetic pole body 3. is arranged, and this third magnetic pole body 5 is screwed into a support rod 9 which is rotatably driven by a drive motor IO via a worm gear reduction mechanism consisting of 10a and 9a. It has a structure in which it is driven in the vertical direction via 8a. In addition, the reference numeral 6 in the figure is a movable yoke which is formed in an annular shape, forms a seat for mounting the third magnetic pole body 5, and also constitutes a part of the yoke 11.

In this way, the third magnetic pole body 5 is connected to the first magnetic pole body 5. Second magnetic pole body2.
3, it comes out from the N pole of the third magnetic pole body 5. 1
The magnetic flux shown by the dotted chain line goes toward the upper surface of the target 12, is superimposed on the main magnetic flux 4, and strengthens the magnetic flux on the upper surface of the target. The degree of this reinforcement differs depending on the vertical position of the third magnetic pole body 5, so by changing the vertical position as the seed line advances on the upper surface side of the target by sputtering, it can be strengthened on the seed line surface. The magnetic field is adjusted to produce a plasma state that is almost the same as that at the beginning of sputtering, and variations in thin film properties are suppressed to a small level. Here, the magnetic flux emitted from the N pole of the third magnetic pole body 5 also bends downward and attempts to encounter the inside of the yoke 1. The second magnetic pole body 2.3 uses a strong permanent magnet that has a large volume and therefore holds a large amount of magnetic energy.
The yoke 11 made of ordinary steel plate (JIS symbol: 5541) is used with the magnetic flux constantly saturated, and the yoke 6
is naturally in a magnetically saturated state, and the yoke 6 always exhibits high magnetic resistance, so passage through the yokes 1 and 6 is blocked, and the third magnetic pole body 5 is in a yoke! 1.6, without being affected by 1. Magnetic flux 7 that is superimposed on the main magnetic flux 4 by the second magnetic pole body 2.3 and changes the magnetic flux distribution on the target surface example
can be formed on the target surface side.

Further, when the target 12 is made of a ferromagnetic material, the third magnetic pole body 5 can be moved closer to the target.
The magnetic flux emitted from the magnetic pole body of the first. The magnetic flux emitted from the second magnetic pole body penetrates the saturated target and exits to the target surface side, increasing the amount of magnetic flux needed to generate annular plasma and efficiently forming a ferromagnetic material thin film on the substrate. be able to.

〔Effect of the invention〕

As described above, the present invention includes a first magnetic pole body whose one end face faces close to the center of the back surface of the plate-shaped target, and a ring-shaped magnetic pole body surrounding the first magnetic pole body. a second magnetic pole whose end face on the same side as one end face of the first magnetic pole body is close to and opposed to the back surface periphery of the plate-shaped target and whose polarity is opposite to that of the one end face of the first magnetic pole body; body, and the first. A planar magnetron system that includes a yoke that magnetically couples the other end faces of the second magnetic pole bodies to each other and has a sputtering cathode that forms an arc-shaped magnetic flux in an annular shape on the surface side of a plate-shaped target to form an annular plasma. In the sputtering apparatus of the above-mentioned first.
a third magnetic pole body between the second magnetic pole bodies; The polarity of each side of the second magnetic pole body is the same as that of the first magnetic pole body.
Since the second magnetic pole bodies are disposed so as to be movable in the direction perpendicular to the surface of the plate-shaped target so as to be the same as the one end face of each of the second magnetic pole bodies, the third magnetic pole body can be moved in the direction perpendicular to the surface of the target. By performing sputtering, the plasma on the target surface side is kept in almost the same state during sputtering, and the bottom film progresses to the oxidized substrate, so when forming thin films on multiple substrates from one target. It is possible to reduce the variation in thin film properties from substrate to substrate compared to the conventional method. In addition, when the material of the target is a ferromagnetic material, the third magnetic pole body can be brought closer to the target to increase the magnetic flux on the target surface side, and the ferromagnetic material film can be efficiently formed on the substrate. I can do it.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the structure of a sputtering cathode according to an embodiment of the present invention. FIG. ii and FIG. 2 are cross-sectional views showing the structure of a conventional speckling cathode. 1.11: Yoke, 2: First magnetic pole body, 3: Second magnetic pole body, 5: Third magnetic pole body.

Claims (1)

[Claims] 1) A first magnetic pole body whose one end face is close to and faces the center of the back surface of the plate-shaped target, and one end face of the first magnetic pole body which is formed in an annular shape surrounding the first magnetic pole body. a second magnetic pole body whose end face on the same side is close to and opposite to the peripheral edge side of the back surface of the plate-shaped target and whose polarity is opposite to that of one end face of the first magnetic pole body; A planar magnetron type sputtering device that is equipped with a yoke that magnetically couples the other end faces of the magnetic pole bodies to each other, and has a sputtering cathode that forms an arc-shaped magnetic flux in an annular shape on the surface side of a plate-shaped target to form an annular plasma. A third magnetic pole body is placed between the first and second magnetic pole bodies,
The polarity of each side of the first and second magnetic pole bodies of the third magnetic pole body is the same as the one end surface of each of the first and second magnetic pole bodies, and is in contact with the surface of the plate-shaped target. A sputtering device characterized by being arranged movably in the vertical direction.