JPH08232063A - Sputtering device - Google Patents

Abstract

PURPOSE: To prevent the non-uniform consumption of a target, the nonuniformity of a thin film and the generation of particles by arranging plural rectangular magnet units on the rear of the rectangular flat target of a magnetron cathode to form a good thin film when the relatively large rectangular substrate stands still. CONSTITUTION: A magnet assembly includes five magnet units, and a spacer 75 is inserted between the yoke 43 and magnet fixing pedestal 4 of the three inner magnet units 74B, and the height of the magnet part is correspondingly decreased as compared with that of the unit 74A. A magnetic shield 49 is arranged between the units. The magnetic field uniformity in a single magnet unit is kept within ±5%, the magnetic field uniformity is controlled within ±5% between the two magnet units 74A, and the magnetic field uniformity is kept within ±5% between the inner magnet units 74B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus, and more particularly, to a surface of a substrate having a relatively large area, with a uniform thickness and a uniform thickness while effectively consuming the entire target surface. The present invention relates to a sputtering device equipped with a magnetron cathode electrode capable of producing a thin film.

[0002]

2. Description of the Related Art In a conventional sputtering apparatus, various types of cathode electrode structures have been proposed. Among them, the magnetron type cathode electrode structure is most often used industrially. The reason is that the film formation speed is high. There are various types of conventional magnetron type electrodes. These types are, for example, “Thin F
ilm Process "(Academic Press Publishing, 1978
Year, edited by JLVossen and W. Kern), pp. 75-173
Pages or "Thin Film Handbook" (published in 1983, edited by the 131st committee of the Japan Society for the Promotion of Science), pages 186-1
It is described on page 89.

At present, among the magnetron type cathode electrodes, the Planar Magnetron cathode electrode provided with a target having a planar shape is most industrially most useful.

Conventionally, in a sputtering apparatus using a flat magnetron cathode electrode having a rectangular plane shape,
When a thin film is formed on a large-area substrate, the following problems (1) to (4) are raised. (1) Enlargement of equipment (2) Non-economical due to non-uniform consumption of target (3) Sputtered film on substrate due to non-uniform ion bombardment on target surface and non-uniform plasma spatial density distribution (4) Generation of particles due to non-uniform ion bombardment on target surface The above problems (1) to (4) will be explained below.

(1) Problem of enlargement of equipment Regarding the relative positional relationship between the substrate and the target in the sputtering equipment, for example, "Dry process application technology" (Haruhiro Kobayashi, Takashi Okada, Naoyoshi Hosokawa, published daily. Kogyo Shimbun Publication, 1984), pp. 63 and 64. Usually, when forming a thin film on a large area substrate,
Substrate translation method is adopted. In this substrate translation method, sputtering is performed while transporting a substrate along a plane parallel to the surface of the rectangular target in a sputtering apparatus having a rectangular target disposed therein, and a thin film is formed on the surface of the substrate. It is a method. For example, Japanese Patent Publication No. 63-65754 (Japanese Patent Application Laid-Open No. 60-86272) discloses a configuration example of a substrate-parallel type sputtering apparatus incorporating a rectangular magnetron cathode electrode. In the substrate translation type sputtering apparatus, the direction of transport of the substrate is selected to be parallel to the short side of the rectangular target in order to obtain a thin film having a uniform thickness.

Generally, when the dimension of the substrate is larger than the length of the short side of the target, in order to form a thin film having a uniform thickness on the substrate, the substrate to be transferred while being deposited is It is required that the substrate transfer distance be sufficiently large. Based on this demand and the demand for improving productivity, the size of a substrate translation type sputtering apparatus for a large substrate tends to be large at present.

[0007] For example, the height of 7
In a sputtering device (ANELVA 3960S) for producing a thin film having a uniform thickness within ± 10% on a glass substrate of 00 mm and a width of 680 mm, the short side length is 250.
mm, a magnetron cathode electrode having a flat target with a long side of 864 mm, a height of 950 mm and a width of 83
Film formation is performed using a 0 mm tray.

Further, a load lock mechanism for carrying in an unprocessed substrate from the atmosphere side and carrying out a film-forming processed substrate to the atmosphere side while maintaining and controlling the sputtering chamber in a vacuum state, and a substrate before film formation are provided. Heating zone to heat,
Due to the necessity of a buffer space for transporting the tray almost continuously, the length of the entire apparatus reaches 10 m to 20 m.

(2) Problem of uneconomicity due to non-uniform consumption of target As described in the above-mentioned documents, the surface of the target is subjected to non-uniform ion bombardment. Therefore, it is consumed unevenly. This uneven wear is
This is caused by utilizing an inhomogeneous magnetic field generated near the target surface in the magnetron cathode electrode.

Conventionally, in order to improve the uneconomical property and the film thickness distribution due to the uneven consumption of the target, for example, a cylindrical coaxial magnetron cathode electrode or a circular flat plate magnetron cathode electrode is used.
In the case of the cathode electrode, a configuration was provided in which the position of the magnet assembly provided in the cathode electrode was changed with time (Japanese Patent Publication No. Sho 5).
5-27627, JP-A-3-6372). This structure is a technique suitable for an electrode having a rotationally symmetrical structure. According to this configuration, in the circular flat magnetron cathode electrode, the consumption of the target can be made uniform by rotating the magnet assembly around a certain rotation axis. On the other hand, such a configuration is not an effective technique as a means for uniformly consuming a rectangular flat target.

(3) Problem of non-uniformity of sputtering film on substrate The non-uniformity of ion bombardment on the target surface of the magnetron cathode electrode affects the homogeneity of the film quality formed on the substrate. This effect is described in the above-mentioned JP-B-63-65.
This will be described below with reference to the configuration described in Japanese Patent Application Publication No. 754 (JP-A-60-86272). In this structure, a thin film is formed by a combination of a rectangular magnetron cathode electrode and a substrate translation type sputtering device.

When a voltage is applied between the cathode electrode and the wall of the vacuum vessel to discharge in a vacuum and a film is formed by sputtering, a rectangular magnetron cathode electrode is formed on the surface of a flat target. Electron drifts along the closed tunnel-like path created by the lines of magnetic force, drawing a loop-shaped trajectory. Drift electrons collide with gas molecules and ionize them, so that a high-density plasma is formed along the locus drawn by the drift electrons. The target surface immediately below the trajectory drawn by the drift electrons receives a strong ion bombardment and is sputtered. Actually, since the drift electrons are extremely large, the trajectory becomes a band shape having a certain width. Therefore, the plasma formed along this band also has a band shape. The sputtered region on the target surface also becomes a band-shaped loop region.

The substrate placed on the transferred tray passes through the front space of the target for film formation. As it passes, a particular location on the substrate passes across the space above the two sputtering strip regions parallel to the long sides of the rectangular target. This upper space is a space having a high plasma density. As is well known, sputtered atoms are emitted not only in a direction perpendicular to the target surface but also in various other directions. Therefore, sputtered particles begin to deposit at a specific location on the substrate before reaching the space above the sputtering zone. Then, the deposition rate increases as the specific location on the substrate approaches the space above the first sputtering zone region. This deposition rate is maximum just above the sputtering zone area. With further transfer of the tray, the deposition rate at a particular location on the substrate once decreases. As a particular location on the substrate approaches the second sputtering zone region, the deposition rate increases again, and at a position directly above the sputtering zone region, the deposition rate again becomes maximum. The deposition rate is maximized for the second time. In subsequent tray transfers, the deposition rate at a particular location on the substrate monotonically decreases as the substrate moves away from the space in front of the target.

As described above, when paying attention to a specific portion on the substrate, the film forming rate changes with time. Further, the incident angle of the sputtered particles deposited on the surface of the substrate and the plasma density of the space in contact with the surface of the substrate change greatly with time. As a result, in the final thin film formed on the substrate, when attention is paid to a specific portion on the substrate, a portion having different physical characteristics is formed in the thickness direction of the film.

Further, for the purpose of film formation on a large substrate, in order to improve the uniformity of the film formation rate and the homogeneity of the film quality,
Consider a magnet assembly in which four magnet units having the same magnetic pole arrangement are arranged. In this case, the film thickness distribution is reduced on the substrate surface facing the magnet portion of the magnet unit. In the case of the above-described four continuous magnets, in addition to the problem of the film thickness distribution, the magnetic fields of a plurality of magnet units interfere with each other, and the magnetic field strength “unevenness” occurs in the magnetic field strength parallel to the target surface. Ion current density, that is, "unevenness" of the amount of sputtering is generated on the target surface according to the distribution of the intensity due to the interference of the magnetic field. Therefore, non-uniformity of the film thickness distribution and the film quality distribution occurs. This has already been mentioned in Japanese Patent Application No. 3-194298 filed by the present applicant. In this prior application, a structure in which a plurality of two kinds of magnet units having different magnetic pole arrangements are alternately arranged to solve the magnetic field intensity “unevenness” was proposed. Although this structure is useful, the strength of the magnetic field tends to be weak due to the cancellation of adjacent opposite poles. Therefore, in order to obtain a strong magnetic field strength, it is necessary to increase the size of the magnet, and there is a problem that the cost for this is high.

(4) Problem of Particle Generation The non-uniformity of ion bombardment on the target surface of the magnetron cathode electrode causes the generation of particles during film formation. As mentioned above, the rectangular magnetron cathode
On the target surface on the gate electrode, one closed band-like region having a width smaller than the width of the target is sputter-etched by ion bombardment. Other regions on the target surface are not sputter-etched, and sputtered atoms that scatter out of the target, scattered by colliding with gas molecules many times in space and depositing thereon. When the sputtering is continued for a long time, a sputtered film is formed on the surface other than the strip-like region to be sputtered on the target surface. The sputtered film deposited on the target is
As it gets thicker, it naturally peels off due to its internal stress,
It becomes a particle. When processing fine patterns on a thin film on a substrate to produce electronic components, particles are regarded as one of the biggest factors in lowering the yield of non-defective products. -The development of a gate electrode is desired.

[0017]

As described above,
Various problems can be pointed out in the sputtering apparatus using the rectangular plate magnetron cathode. An object of the present invention is to solve the problem that ions bombard a target non-uniformly, to provide a cathode electrode structure capable of forming a good thin film while a relatively large rectangular substrate is stationary, and ,
An object of the present invention is to provide a sputtering apparatus capable of reducing the size of the entire apparatus. Another object of the present invention is to provide a cathode electrode structure that solves the problems of uneconomical consumption due to uneven consumption of rectangular targets, inhomogeneity of thin films deposited on a substrate, and generation of particles. An object is to provide a sputtering device having the same.

[0018]

A first aspect of the present invention is directed to a vacuum container provided with an exhaust system for evacuating the interior thereof, and a substrate holding member mounted inside the vacuum container for mounting a substrate to be subjected to film formation processing. And at least one magnetron cathode electrode provided with a rectangular planar target for forming a film on the substrate, which is arranged in a positional relationship facing the substrate, and a gas is circulated inside the vacuum container. The present invention relates to a sputtering apparatus including a gas control system that appropriately maintains an internal pressure and a power supply system that supplies electric power to the magnetron cathode electrode, and has the following features. (A) The magnetron cathode electrode includes a plurality of magnet units on the back surface of one rectangular planar target. (B) The magnet unit has a rectangular cross section parallel to the target surface, and a plurality of magnet units are arranged such that a long side is adjacent to a long side of an adjacent magnet unit. (C) The magnetic poles of the magnet units are the same in all the magnet units included in the same magnetron cathode electrode. (D) The magnet unit has a structure that causes an annular electron drift motion locus on the surface of the target. (E) Among the plurality of magnet units, the strength of the magnetic field generated on the target surface by the two magnet units at both ends in the short side direction of the magnet unit is equal to the magnetic field generated on the target surface by the magnet units inside thereof. Greater than strength. (F) The magnetic shield wall is arranged between the adjacent magnet units.

That is, according to the present invention, a plurality of magnet units are arranged on the back surface of one target.
Thus, a plurality of annular trajectories due to drift electrons are formed on the surface of one target. The magnetic poles of the magnet units are made equal to each other. When the magnetic poles of the plurality of magnet units are arranged to be equal to each other and the magnetic poles are arranged side by side, the neighboring magnetic poles do not cancel each other out, and the magnet strength does not need to be increased more than necessary. However, when the magnet units having the same magnetic pole arrangement are arranged side by side, the magnetic field strength “unevenness” is likely to occur as described in the item of the related art. That is, when a plurality of equivalent magnetic units having a slight difference in magnetic field distribution are arranged side by side, the difference in magnetic field distribution is emphasized as a result of mutual interference of magnetic fields, and a magnetic field distribution having a strong irregularity as a whole is generated. It is formed, and this becomes a major factor that adversely affects the discharge characteristics and the film thickness distribution characteristics of the magnetron cathode. In order to solve this, in the present invention, a magnetic shield wall made of a ferromagnetic material is arranged between the magnet units. The magnetic shield wall has a function of preventing mutual interference between the magnet units.

Further, in the present invention, regarding the strength of the magnetic field created by the magnet units on the target surface, the magnetic units at both ends have stronger magnetic fields than the inner magnet units. In general, regarding the film thickness distribution of the substrate, the film thickness near the center of the substrate tends to increase, and the film thickness tends to decrease toward the edge of the substrate. Therefore, if the magnetic field near both ends of the target is made stronger than near the center, improvement of the film thickness distribution can be expected. According to the present invention, when the rectangular magnet units are arranged so that their long sides are adjacent to each other, the magnetic field created by the two magnet units on both sides is made larger than the magnetic field created by the inner magnet unit, and the film is formed. The thickness distribution is improved. Here, as an index of the magnetic field strength of the magnet unit, as shown in FIG. 20 (B), the average value BAV of the effective magnetic field strength on the circular locus can be used. In order to control the strength of the magnetic field generated by the magnet unit on the target surface, there is a method of adjusting the material and size of the magnet unit itself, and also a method of adjusting the distance between the magnet unit and the target.

Here, the Japanese Patent Publication No. 63-
The difference between the electrode structure disclosed in No. 65754 and the electrode structure according to the present invention will be described. In the electrode disclosed in the prior art, one cathode electrode includes one magnet unit, and only one circular locus is formed by drift electrons. By providing a plurality of such cathode electrodes, the movement directions of the annular trajectory are made equal between adjacent cathode electrodes. The cathode electrode of this sputtering apparatus is effective when forming a thin film while moving the substrate.

On the other hand, in the present invention, one cassette is used.
In the electrode, a plurality of magnet units are provided in it,
These magnet units are arranged in parallel with each other having the same magnetic pole arrangement to form a plurality of circular loci due to drift electrons on one target. In the ring trajectory of the neighbors, the movement direction of the electrons is the same.

According to a second aspect of the present invention, in the first aspect of the present invention, as a means for increasing the strength of the magnetic field generated on the target surface by the magnet units on both sides higher than that of the inner magnet unit, the height of the magnet portion of the magnet unit is increased. The height is adjusted. That is, the height of the magnet portions of the magnet units on both sides is made larger than that of the inner magnet units.
Here, the “height” of the magnet portion refers to the distance between the two magnetic pole surfaces (N-pole surface and S-pole surface) of the magnet portion. If the materials of the magnets are the same, increasing the height of the magnet portion results in a stronger magnet.

A third aspect of the present invention is intended to equalize the magnetic fields of the magnet units in the first aspect. That is, the magnetic field uniformity within ± 5% is provided within a single magnet unit, and the magnetic field uniformity within ± 5% is provided between the magnet units. This eliminates uneven distribution and instability of the discharge, and improves the film thickness distribution on the substrate.

Here, regarding the magnetic field homogeneity in a single magnet unit and the magnetic field homogeneity between magnet units,
The definition is described below.

In FIG. 20A, the magnet unit 80
Magnet unit 80 on the target surface 82 above the
Consider the strength of the magnetic field created by. On the target surface 82, the point immediately above the center of the magnet unit 80 is set as the point O, which is the origin of the coordinate axis. X in the direction of the short side of the magnet unit 80
The axis, the long side direction is the Y axis, and the direction perpendicular to the target surface 82 is the Z axis. Now, the strength of the magnetic field at an arbitrary point on the target surface 82 is represented by the magnetic flux density B. This magnetic flux density B is a vector, and its X-axis direction component is BX, Y
Let the axial component be BY and the Z axial component be BZ. The projection component of the magnetic flux density B on the XY plane is represented by BXY. This BXY is equal to the composite vector of BX and BY.
It is the strength of the magnetic field on the target surface that determines the amount of sputtering of the target, and the component orthogonal to the electric field, that is, the absolute value of BXY, has the greatest effect on the amount of sputtering. Therefore, as an index indicating the strength of the magnetic field of the magnet unit, the absolute value of the component BXY parallel to the target surface of the magnetic flux density on the target surface (hereinafter, referred to as effective magnetic field strength) is most suitable.

The above-mentioned effective magnetic field strength is used to evaluate the magnetic field uniformity of the magnet unit. When the effective magnetic field strength is measured at each point on the target surface and the points where the large strength is obtained are connected, an annular trajectory 84 is obtained. This annular trajectory 84 matches the position of the target erosion area. If the effective magnetic field strength measured along this annular trajectory 84 is uniform at any point, the target will be sputtered uniformly along the erosion region. In the present invention, the degree of distribution of the effective magnetic field intensity measured along the above-described annular locus 84 is defined as the magnetic field uniformity, and the magnet unit 80 is manufactured so that this is within ± 5%. However, in order to obtain the magnetic field uniformity, a region near the short side of the magnet unit is excluded. 20B, the horizontal axis represents the distance along the annular trajectory 84, and the vertical axis represents the effective magnetic field strength (B
7 is a graph showing the magnetic field uniformity when taking the absolute value of XY). The effective magnetic field strength is large at the points D and F where the annular trajectory 84 is closest to the short side of the magnet unit 80, but the effective magnetic field strength is large in the long side direction (Y-axis direction) of the magnet unit 80. Is almost constant. Assuming that the length of the long side of the magnet unit 80 is LA, it is desirable to make the magnetic field uniformity within ± 5% at least within a range of 80% of LA. Therefore, the term "magnetic field uniformity" in the present invention means that the degree of distribution of the effective magnetic field intensity measured along the above-mentioned annular locus 84 is measured in an area within 80% of the long side direction of the magnet unit. Can be.

Next, the magnetic field uniformity between the magnet units will be described. In FIG. 20B, the average value BAV of the magnetic field uniformity is obtained for one magnet unit. This value can be determined for each magnet unit. Then, the average value BAV is compared between the magnet units, and the degree of distribution thereof is defined as the magnetic field homogeneity between the magnet units. In this invention, the magnetic field uniformity between the magnet units is ± 5.
By controlling the ratio within%, it is possible to prevent the variation of the film thickness distribution due to the variation of the magnetic field strength between the magnet units.

By the way, as described above, the magnetic field homogeneity of a single magnet unit and the magnetic field homogeneity between magnet units are ±
The reason for limiting to within 5% is as follows. Since the magnetic field strength distribution is directly reflected on the film thickness distribution of a thin film formed by sputtering, a uniform distribution is desired. The extent to which the uniformity of the film thickness distribution within the substrate must be kept depends on the application field. However, the maximum allowable deviation of the film thickness distribution of a thin film, which is currently desired in many electronic device manufacturing processes, is often ± 5%. Considering this point, in order to obtain a film thickness distribution with good uniformity, it is necessary to suppress the magnetic field intensity distribution of the magnet unit to at most ± 5%. Also, if the magnetic field uniformity of the magnet units and the magnetic field uniformity between the magnet units are good, a plurality of rectangular annular electron drift trajectories can be efficiently and uniformly generated on the target surface as a whole magnet assembly. Thereby, the discharge on the target surface can be stably maintained without uneven distribution. For the above reasons, the magnetic field uniformity of the magnet units and the magnetic field uniformity between the magnet units are each set to within ± 5%. Of course, as the maximum allowable deviation of the film thickness distribution in the substrate becomes smaller, the uniformity of the magnetic field intensity distribution in the magnet unit and between the magnet units must be limited to a narrower range. However, as the homogeneity of the magnetic field is limited to a narrower range, it is technically difficult to consider the magnet design and manufacturing for realizing it. Therefore, from the viewpoint of cost effectiveness, the uniformity of the magnetic field intensity distribution is limited to about ± 5%.

The degree of variation in the magnetic field strength distribution of the magnet unit largely depends on the machining dimension accuracy of the pole pieces. For example, if the processing dimensional accuracy is ± 0.2 mm, the worst is 0.4.
mm differences may occur. In that case, a magnetic field intensity difference of about 7% occurs at a point 32 mm above the pole surface (corresponding to the target surface). When the processing dimensional accuracy is improved to ± 0.05 mm, the above-mentioned difference in magnetic field strength is about 2%. In this description, it is assumed that the residual magnetic flux density of the magnetic pole constituting material is uniform in all regions of the magnetic pole.
In practice, non-uniformity of material properties cannot be ignored. Therefore, in order to keep the magnetic field uniformity of the magnet unit within ± 5%, it is necessary to consider both the machining dimensional accuracy and the material homogeneity. As an example of means for achieving a predetermined magnetic field uniformity, the material and shape of each magnetic pole piece constituting the magnet unit are examined, and the residual magnetic flux density of each magnetic pole piece is determined to be within 12000G ± 500G. did. The machining accuracy of the pole piece was set to ± 0.05 mm or less, and attention was paid to the assembly accuracy. This allows
Improved the magnetic field uniformity in the magnet unit.

A fourth aspect of the present invention is one of the constitutions of the third aspect.
The feature that a magnetic shield wall is arranged between adjacent magnet units is removed.

A fifth aspect of the invention is the fourth aspect of the invention in which the magnet unit is reciprocally movable in the direction of the shorter side of the rectangle. When the rectangular magnet unit is moved in the short side direction, the annular trajectory caused by the drift electrons moves perpendicularly to the longitudinal direction, and a target portion that has not been sputtered is sputtered. Thereby, the film thickness distribution on the substrate is improved, and the use efficiency of the target is dramatically improved. For example, by making the amplitude of the reciprocating motion equal to the length of one magnet unit in the short side direction, it is possible to uniform the region of the target to be etched.

A sixth aspect of the invention is one of the first aspect of the invention.
Except for the feature of arranging magnetic shield walls between adjacent magnet units, and as means for increasing the strength of the magnetic field created on the target surface by the magnet units on both sides than that of the inner magnet units, the magnet units are It is a feature that adjusts the distance from the target to the target. That is, the distance from the target-side magnetic pole surface of the magnet units on both sides to the target surface is made smaller than that of the inner magnet units. When using exactly the same magnet unit, the closer the magnet unit is to the target, the stronger the magnetic field on the target surface can be made.

A seventh invention is a concrete embodiment of the magnet structure for producing an annular electron drift motion locus on the surface of the target in the above-mentioned first, fourth and sixth inventions. That is, the magnet unit is composed of a yoke, a center magnet fixed on the yoke, and a peripheral magnet fixed on the yoke and surrounding the center magnet. The central magnet and the peripheral magnet have magnetic pole surfaces on the surface fixed to the yoke and the surface on the target side, and the magnetic pole on the target side of the central magnet and the magnetic pole on the target side of the peripheral magnet have opposite polarities. .

An eighth aspect of the invention is one of the constitutions of the first aspect.
Except for the feature of arranging the magnetic shield wall between the adjacent magnet units, and instead of arranging the magnet units having the same magnetic pole arrangement, magnet units having opposite polarities are arranged next to each other.

In a ninth aspect based on the eighth aspect, the magnet unit is composed of a frame-shaped rectangular magnet without a central magnet and has a magnetic pole surface perpendicular to the target surface.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION Before describing the embodiments of the present invention, a technique closely related to the present invention will be described. FIG.
FIG. 1 is a front sectional view showing a basic configuration of a sputtering apparatus to which the present invention is applied. This sputtering apparatus includes a substrate tray insertion chamber 1 and a sputtering chamber 2 for forming a thin film on the surface of a substrate mounted on the tray.
And a substrate tray take-out chamber 3. The substrate tray insertion chamber 1, the sputtering chamber 2, and the substrate tray unloading chamber 3 are connected in series. Each of these chambers is formed by a vacuum container having a structure capable of independently evacuating and maintaining / managing in a vacuum state. Substrate tray insertion chamber 1
A gate valve 4 is provided between the sputtering chamber 2 and the sputtering chamber 2, and a gate valve 5 is provided between the sputtering chamber 2 and the substrate tray take-out chamber 3.

The sputtering chamber 2 is usually maintained and controlled in a vacuum state. The substrate tray insertion chamber 1 can be opened to the atmosphere by using a leak valve 6, and the substrate tray unloading chamber 3 can be opened to the atmosphere by using a leak valve 7. In the substrate tray insertion chamber 1, the air is exhausted in the direction of arrow 10 by an exhaust pump (not shown) via an exhaust pipe 8. In the substrate tray take-out chamber 3, the gas is exhausted in the direction of arrow 11 by an exhaust pump (not shown) via the exhaust pipe 9. The left end of the substrate tray insertion chamber 1 in FIG. 1 is an entrance door 12, and the right end of the substrate tray take-out chamber 3 in FIG. 1 is an exit door 13.

The tray 14 on which the substrate is mounted is carried into the substrate tray insertion chamber 1 through the entrance door 12. The tray 14 is an instrument for holding the substrate. This substrate is a relatively large substrate. After the tray 14 is carried in, with the entrance door 12 and the gate valve 4 closed,
Exhaust is performed using an exhaust system. When the internal pressure of the substrate tray insertion chamber 1 is sufficiently reduced, the gate valve 4 is opened, and the tray 14 is guided by a rail (not shown) and transported in the direction of arrow 15 to the sputtering chamber 2. Sent in.

In the sputtering chamber 2, a thin film forming mechanism, which will be described later, forms a thin film on the surface of the substrate mounted on the tray 14 by the sputtering method. In this embodiment, when a thin film is deposited on a substrate, the tray 14
Is at rest. After forming the thin film on the substrate, the tray 14 is fed into the substrate tray take-out chamber 3 via the gate valve 5. After the tray 14 has been sent to the substrate tray unloading chamber 3, the gate valve 5 is closed, and the
The valve 7 is opened. Thus, the substrate mounted on the tray 14 is placed in an atmospheric pressure environment. Thereafter, the take-out door 13 is opened, and the tray 14 is taken out.

In the sputtering chamber 2, gas is introduced from a cylinder (not shown) through the gas introduction pipe 16 in the direction of arrow 18a. In the sputtering chamber 2, the gas is exhausted by an exhaust pump (not shown) through the exhaust port 17 in the direction of arrow 18 b. As a result, in a state where the flow rate of the introduced gas and the flow rate of the exhaust gas are balanced, the sputtering chamber 2 is maintained in a discharge state, and 10-3 suitable for performing sputtering.
It is maintained at a constant pressure within a pressure range of -10 to Torr.

Gate valve 4 in sputtering chamber 2
A substrate heating lamp 19 is disposed at a location near (the front side). The substrate heating lamp 19 is provided as needed. By the heat ray radiation of the substrate heating lamp 19, the temperature of the substrate can be increased before the thin film is formed.
A magnetron cathode electrode 20 (hereinafter, referred to as a cathode electrode 20) having a large target in the form of a rectangular plane is disposed on the rear side of the sputtering chamber 2 via an insulator 21. A target assembly 22 is mounted on the cathode electrode 20. The upper surface of the target assembly 22 in FIG. 1 is the target surface. The cathode electrode 20 has a power supply 24 and a power supply line 25 between the cathode electrode and the power supply.
And a power supply system 23 consisting of a connection 26 between the power supply and the ground
Is connected. With this power supply system 23, the cathode electrode 20
Is supplied with power.

In the sputtering chamber 2, the tray 14
Is stationary with respect to the cathode electrode 20. In this stationary state, the substrate on the tray 14 faces the target surface of the target assembly 22. Sputtered particles flying from the target assembly 22 are deposited on the opposite surface of the substrate,
A thin film is formed on the substrate. In the example shown in FIG. 1, a combination of one tray 14 and one cathode electrode 20 is shown, but an arbitrary number of cathode electrodes 20 can be provided in the sputtering chamber 2. . The wall of the sputtering chamber 2 is grounded.

FIG. 2 is a front sectional view of a deep cathode electrode 20 relevant to the present invention. First, this cathode electrode 20
The structure of is specifically described. The cathode electrode 20 is composed of an electrode housing 31, a magnet assembly 32 disposed inside the electrode housing 31, and a target assembly 22. The cathode electrode 20 has an opening 34 formed in a wall 33 of a vacuum chamber forming the sputtering chamber 2,
It is attached via an insulator 21. Cathode electrode 20
Is attached to the opening 34 so that the target surface of the target assembly 22 is exposed to the vacuum chamber side. Illustrations of a fixture for attachment, a clamp mechanism and the like are omitted.

The target assembly 22 includes the target plate 3
5 and a target holding jig 36 and a target back plate 37, which are fixed to the electrode housing 31 by a coupling (not shown).

A magnet assembly 32 is disposed in a concave space 38 formed inside the electrode housing 31. More specifically, in the concave space 38, the magnet unit 4 including the central magnet 41, the peripheral magnet 42, and the yoke 43.
4 are provided. The five magnet units 44
The size, material, and magnetic pole arrangement are all the same. Details of the magnet unit will be described later. Magnet unit 4
A magnetic shield 49 made of a ferromagnetic material is arranged between the four and outside the whole of the five magnet units 44.
The magnet unit 44 and the magnetic shield 49 are the magnet fixing base 4
It is fixed to 8. As described above, the magnet assembly 32 includes the five magnet units 44, the magnetic shield 49, and the magnet fixing base 48.

Although not shown, the concave space 38
, Cooling water is introduced from outside the electrode housing 31. The cooling water contacts the target back plate 37 to cool it. When discharging, the heat generated on the target surface of the target assembly 22 is radiated to the outside by using cooling water as a medium.

Electrode housing 31 and target back plate 37
An O-ring 39 is provided between them to maintain airtightness. The airtightness between the electrode housing 31 and the insulator 21 is maintained by the O-ring 40, and the airtightness between the insulator 21 and the wall 33 of the vacuum vessel is maintained by the O-ring 30.

It is not desirable that the surface of the target assembly 22 exposed to the vacuum side other than the surface to be sputtered is bombarded with ions. Therefore, a target shield member 47 is provided around the opening 34 on the inner surface of the wall 33 in order to prevent the surface not to be sputtered from being bombarded with ions.

FIG. 3 is a plan view of the magnet assembly 32. 5
Between the four magnet units 44 and the five magnet units 4
A magnetic shield 49 is provided outside the entirety of 4.
The magnetic shield 49 is made of a material having a high magnetic permeability, such as soft iron. Between the magnet units 44, there is a magnetic shield 49a slightly longer than the long side of the magnet unit 44, and this is connected to the surrounding magnetic shield 49b. The magnet unit 44 and the magnetic shield 49 are fixed on a ferromagnetic magnet fixing base 48 (see FIG. 2), and the lower part is also magnetically shielded. , Magnet unit 4
4 are absorbed by the magnetic shield 49,
Mutual interference of magnetic fields is prevented. Thereby, the magnetic field distribution of the entire magnet assembly can be maintained in a well-balanced manner. If the magnet fixing base 48 and the magnetic shield 49 are not provided, a magnetic field distribution is biased in a diagonal direction of the magnet assembly 32 due to mutual interference of the magnetic fields, and a thin film having a uniform thickness cannot be produced.

The magnetic shield 49b outside the short side of the magnet unit 44 can be omitted. However, when the magnetic field near the short side of the magnet unit 44 is stronger than the magnetic field at the central portion in the long side direction of the magnet unit, it is preferable to attach the magnetic shield 49b also to the outside of the short side.

Next, the structure of the magnet unit 44 will be described. 4A is a cross-sectional view of the magnet unit cut along a plane parallel to the short side, FIG. 4B is a plan view of the magnet unit,
(C) is a perspective view thereof. The magnet unit 44 is composed of an elongated plate-shaped central magnet 41 and a rectangular ring-shaped peripheral magnet 42 arranged around the yoke 43 having a substantially rectangular planar shape. In this embodiment, the length LA of the long side of the magnet unit 44 is 630 mm, and the length of the short side is 110 mm. The magnetic pole on the yoke 43 side of the center magnet 41 is an N pole, and the opposite side is an S pole.
The magnetic pole on the yoke 43 side is an S pole, and the opposite side is an N pole. Due to this magnetic pole arrangement, lines of magnetic force 45 from the peripheral magnet 42 to the center magnet 41 are formed on the target side. Accordingly, the lines of magnetic force exit from the surface of the target above the peripheral magnet 42, and enter the surface of the target above the center magnet 41. The lines of magnetic force form an annularly closed tunnel path. The magnetic field uniformity of the single magnet unit 44 is within ± 5%, and the magnetic field uniformity between the magnet units is also within ± 5%.

When a negative high potential is applied to the cathode electrode 20 in the state where the magnetic force lines 45 are generated as described above, the target
An electric field perpendicular to the get surface is generated. The electrons drift along the tunnel path on the target surface based on the combination of the electric field perpendicular to the target surface and the magnetic field forming the tunnel path. The electron drift motion describes an annular trajectory. As a result, a discharge of a low voltage and a large current is generated, and this discharge enables a sputtered film to be formed on a substrate at a high speed.

FIG. 5A is a plan view showing the trajectory of electron drift motion on the target plane, and FIG. 5B is a sectional view of the magnet assembly 32 corresponding thereto. Electron is
A drift motion is performed along the annular trajectory 46 in the direction indicated by the arrow. The annular trajectory 46 is shown as a closed thin line in the drawing, but is actually a band shape having a certain width. Ions are generated by electrons drifting and colliding with gas molecules. Therefore, the distribution of the ion current density can be regarded as a projection of the spatial density of the drift electrons passing on the target surface 28 onto the target surface. The trajectory of the drift electrons is not a single thin line but a wide space having a probability distribution. In addition, ions bombard the target and sputter it,
The wide ion current density distribution corresponds to the target sputtering depth distribution. In each annular trajectory 46,
The two parallel long sides 46a and 46b adjacent to each other are
The drift directions are opposite to each other.

FIG. 6 is a cross-sectional view showing magnetic lines of force of the magnet assembly 32, which is cut along a cross section parallel to the short side of the magnet unit. This drawing relates to a magnet assembly composed of four magnet units and shows only the right side from the center line. It can be clearly seen that the magnetic field lines 45 of each magnet unit are absorbed by the magnetic shield 49, and as a result, mutual interference of magnetic fields is suppressed.

In the above-mentioned technique, the surface of the target of the cathode electrode 20 has a rectangular and relatively large area. On the target surface, a portion to be sputtered is specified as a band-like portion of an annular trajectory formed by lines of magnetic force of the magnet unit 44. By forming a plurality of annular erosion regions on one target, it is possible to form an erosion region over as large an area as possible. Thereby, the utilization efficiency of the target having a relatively large area (the ratio of the annular locus area to the total area of the target) can be improved.

As described above, the interaction between the electric field and the magnetic field formed by the central magnet and the peripheral magnets causes
An annular locus of drift electrons is formed on the get surface. The required magnetic field is, for example, on the order of 200 to 500 Gauss as a magnetic field component parallel to the target surface.

FIG. 7 is a front sectional view of a cathode electrode in another technique deeply related to the present invention. In this cathode electrode, the configuration and relative positional relationship of the electrode housing, the target assembly, the wall of the sputtering chamber and its opening, the plurality of O-rings for maintaining airtightness, the target shield member, etc. are shown in FIG. It is the same as the case of the cathode electrode. Therefore, the same components are denoted by the same reference numerals, and description thereof will be omitted. The characteristic part of the cathode electrode in FIG. 7 is that the magnet assembly is movable.
Hereinafter, the configuration of the magnet assembly will be described.

The magnet assembly 51 includes four magnet units 4
4, a magnetic shield 49 is provided between the magnet units, and a magnet fixing pedestal 48 is provided below the magnet units.
In the magnet assembly 51 of the present embodiment, the magnet unit 44
Since it is a piece, the concave space 3 inside the electrode housing 31
8, a space 52 having the same width as the width of one magnet unit remains. Therefore, in the concave space 38 in the electrode housing 31, the magnet assembly 51 is
Or, it is possible to reciprocate in the direction of 54.
The amplitude of the reciprocation of the magnet assembly 51 is substantially equal to the width of one magnet unit. In the magnet assembly 51 of the present embodiment,
A moving mechanism for moving this is provided.

The moving mechanism will be described with reference to FIGS. 7 and 8. FIG. 8 is a sectional view taken along line VIII-VIII of FIG. 7.
In FIG. 7, the magnet assembly 51 is supported by a support base 55. The magnet assembly 51 is supported by a support 55 using screws (not shown) or the like.
Fixed to. Further, the support table 55 is fixed to the driving plate 56. As shown in FIG. 8, a rectangular guide hole 57 is formed in the center of the drive plate 56, and a circular cam 58 that is in contact with a part of the inner wall is arranged in the guide hole 57.
The cam 58 is rotated by a cam shaft 59.

Four slide bearings 60 are fixedly mounted on the bottom of the drive plate 56. Two guide bars 61 are disposed in the longitudinal direction near the bottom of the concave space 38, and the slide bearing 60 is inserted through the guide bar 61. Both ends of each guide bar 61 are fixed by receiving tubes 62 provided on the inner wall surface of the concave space 38 of the electrode housing 31. With such a configuration, the drive plate 56 is guided by the guide bar 61 and is movable in the direction of the arrow 53 or 54. When the cam shaft 59 rotates, the drive plate 56 reciprocates in the concave space 38 according to the contact relationship between the cam 58 and the guide hole 57. Since the circular cam 58 is directly connected to the camshaft 59 in an eccentric state from the center thereof, when the rotational speed of the camshaft 59 is constant, the speed of the reciprocating motion of the driving plate 56 is slow at both ends, and the center portion is And it becomes a simple vibration motion.

The shape of the guide hole 57 is not limited to a rectangular shape, and may be an elliptical shape or any similar shape as long as the drive plate 56 can be reciprocally moved by the rotational movement of the cam 58. can do.

In FIG. 7, the cam shaft 59 is connected to the output shaft of the motor 63 and is rotated by the motor 63. The motor 63 is arranged outside the electrode housing 31, and is fixed to the electrode housing 31 by a support frame 64 and a support base 65. The camshaft 59 is a radial bearing 6 that supports the camshaft while rotating it smoothly.
6 and an oil seal 67 for sealing the cooling water in the electrode housing while rotating. With the above configuration, the motor 63
When the cam shaft 59 rotates in a certain direction by the rotating operation of the magnet assembly 51, the magnet assembly 51 moves to the concave space 3 of the electrode housing 31.
8 reciprocate inside.

FIG. 9A is a plan view showing an erosion region formed on the target surface, and FIG. 9B is a sectional view thereof. This erosion region 69 corresponds to the electron drift motion trajectory 46 as shown in FIG. The amount of sputter etching in the erosion region is indicated by the hatched portion S in FIG. In this embodiment, since the four magnet units move in the short side direction, the erosion area 69 also reciprocates in the direction of the arrow 53 or 54. as a result,
The hatched portion S in (B) reciprocates, and as a whole, a dashed line 7
The uniform sputter etching as indicated by 0 is performed. As a result, the utilization efficiency of the target 35 is improved.

In particular, by making the amplitude of the reciprocating motion of the entire magnet assembly equal to the width of the magnet unit, the film thickness distribution within the substrate and the target utilization efficiency which are almost the same as those when the reciprocating motion of a single magnet unit is performed. It is possible to increase the average film formation rate while maintaining the above, and to improve the uniformity of the film quality in the substrate.

10 to 12 are plan views showing modified examples of the magnetic shield means in the magnet assembly. In each case,
It is an example of the magnet assembly containing four magnet units. FIG.
In the example of No. 0, a ferromagnetic block 71 made of iron, nickel or the like is inserted between the short side of the magnet unit 44 and the magnetic shield 49b outside the short side. Magnet unit 44
When the magnetic field near the short side of is strong, it is preferable to adopt such a configuration. Thereby, the magnetic field distribution and the thickness distribution of the thin film can be adjusted. In the example of FIG.
The ferromagnetic block 72 is inserted in the gap between the magnet unit 44 and the magnetic shield 49a. In the example of FIG. 12, a ferromagnetic plate 73 is attached to the surface of the magnet assembly 32 to block the magnetic field. The ferromagnetic plate 73 is attached only near the short side of the magnet unit. This example
It is effective for a wide range of magnetic field adjustment and film thickness adjustment.

FIG. 13 is a front sectional view of a cathode portion according to an embodiment of the present invention. In this cathode electrode, the configuration and relative positional relationship of the electrode housing, the target assembly, the wall of the sputtering chamber and its opening, the plurality of O-rings for maintaining airtightness, the target shield member, etc. are shown in FIG. It is the same as the case of the cathode electrode. Therefore, the same components are denoted by the same reference numerals, and description thereof will be omitted. Compared to the cathode electrode of FIG. 2, the cathode electrode of FIG. 13 is characterized by the magnet assembly. The structure of this magnet assembly will be described below.

This magnet assembly includes five magnet units, of which two magnet units 74A on both sides are included.
And the three inner magnet units 74B have different configurations. The basic configuration of the magnet units 74A on both sides is the same as that of the magnet unit 44 shown in FIG. On the other hand, in the inner magnet unit 74B, a spacer 75 is inserted between the yoke 43 and the magnet fixing base 48. As a result, the height of the magnet portion is smaller than that of the magnet unit 74A. The height position of the magnetic pole surface of the magnet unit is the same for all five magnet units. A magnetic shield 49 is placed between the magnet units.
Is arranged. The magnetic field uniformity within the single magnet unit is within ± 5%, the magnetic field homogeneity within the two magnet units 74A on both sides is within ± 5%, and the magnetic field homogeneity within the inner magnet unit 74B is ± 5%. It is within%.

Next, the function of this cathode electrode will be described. FIG. 14A shows a state in which four identical magnet units are arranged in parallel. In this case, four magnetic field distributions corresponding to the magnet units are formed on the surface of the target 35, and the strengths of these magnetic field distributions are substantially equal to each other.
FIG. 14B is an example in which the height (hence the volume) of the magnet portion is different, as in the cathode electrode of FIG.
That is, the height of the magnet portions of the magnet units 74A on both sides is larger than the height of the magnet portions of the inner magnet units. It should be noted that this drawing shows an example including four magnet units. This way, target 3
The strength of the magnetic field on the surface of 5 is strong on both sides and weak on the inside. In the drawing, a strong magnetic field is indicated by H, and a weak magnetic field is indicated by L. In H, the magnetic field intensity is large, the ion current density is large, and the sputter etching amount is large. Conversely, with L, the amount of sputter etching is small.

FIG. 14C shows another means for strengthening the magnetic fields on both sides. In this example, the magnet units themselves are all the same, but the magnet units 76 on both sides are identical.
Insert a spacer 77 between A and the magnet fixing base 48,
Only the magnet units 76A on both sides are brought close to the target 35. Therefore, there is a step between the magnetic pole surfaces of the magnet units 76A on both sides and the magnetic pole surfaces of the inner magnet unit 76B. By such means, the strength of the magnetic field on the surface of the target 35 can be increased on both sides and reduced on the inside. For example, when the step is 3 mm, the magnetic field strength of L (effective magnetic field strength described above) is 200 G
(Gauss), the magnetic field strength of H becomes 225G.

FIG. 15 is a graph showing contour lines of film thickness distribution when a film is formed on a substrate using the magnet assembly shown in FIG. 14 (A). The conditions were as follows: the distance between the target and the substrate was 135 mm; the pressure of Ar gas was 5 mTorr;
Copper was used as the get material. Both the magnet assembly and the substrate are stationary. The film thickness of the substrate 14 was measured within a rectangular measurement range 78. The dimension of the target effective area 79 is such that the direction parallel to the short side of the magnet unit, that is, the X direction is LX =
LY = 450 mm in the direction parallel to the long side of the magnet unit, that is, in the Y direction, is 360 mm. The uniformity of the film thickness distribution within the effective area 79 was ± 14.3%. The figures of the contour lines in the figure show the film thickness in percentage when the maximum film thickness is 100%. What can be seen from this graph is that the film thickness distribution at both ends in the X-axis direction is particularly undesirable.

On the other hand, FIG. 16 is a graph of the film thickness distribution when the magnet assembly shown in FIG. 14C is used. The film forming conditions are the same as in FIG. The step between the magnet units on both sides and the inner magnet unit is 5 mm. In this case, an effective area 7 of 360 mm × 450 mm
Within the range of 9, the uniformity of the film thickness distribution was greatly improved to ± 8.1%. FIG. 17 shows a case where the step is 3 mm.
6 is a graph similar to FIG. 6, and the uniformity of the film thickness distribution in the effective region 79 was ± 11.1%. Thus, by increasing the strength of the magnetic field on both sides in the X-axis direction, the uniformity of the film thickness distribution was greatly improved.

In order to increase the strength of the magnetic field on both sides in the X-axis direction, in addition to the above-mentioned means, the dimensions of the central magnet and the peripheral magnets in the horizontal cross section are changed, and the materials of the magnets are changed. Also, the same effect can be obtained by these means. In addition, the space in FIG.
The support 75 may or may not be used depending on the film forming conditions.
If it is used, it becomes the same as FIG. 14B, and if it is not used, the effect of the step as shown in FIG. 14C is added.

FIG. 18 is a front sectional view of a cathode electrode according to another embodiment of the present invention. This cathode electrode is shown in FIG.
The moving mechanism shown in FIGS. 7 and 8 is combined with the cathode electrode magnet assembly shown in FIG. The structure of the moving mechanism is the same as that shown in FIGS. 7 and 8. Therefore, the same components are denoted by the same reference numerals, and description thereof will be omitted.

Also in this embodiment, as in the case shown in FIGS. 7 and 8, the circular loci of the drift electrons periodically move on the target plane.
The target is uniformly consumed except at both ends in the moving direction, thereby improving the use efficiency of the target. Moreover, in this embodiment, as in the embodiment of FIG. 13, the magnetic field near both ends in the moving direction is stronger than the inside, so that the target portions at both ends in the moving direction are less likely to be uniformly consumed by such a moving mechanism. Are more actively sputtered, and utilization efficiency is further improved.

FIG. 19 shows another type of magnet unit having a structure different from that of the magnet unit described above. FIG. 19A is a perspective view of the magnet unit.
(B) is a front sectional view of a magnet assembly including this magnet unit. In this magnet unit 85, the central magnet does not exist, only the rectangular and annular magnet portion 86 exists, and the inner wall surface thereof is the S pole and the outer wall surface is the N pole. That is, when the magnet unit 85 is arranged in the electrode housing, the magnetic pole surface is perpendicular to the target surface. This magnet unit 85 can be used as the magnet unit in the embodiment of FIG. 13 or FIG. For example, as shown in FIG. 19B, by combining the magnet units 85A and 85B, the magnetic field created by the outer magnet unit 85A on the target surface is generated by the inner magnet unit 85B.
Larger than the magnetic field created by. Inner magnet unit 85
A is placed on the spacer 87 to reduce the height of the magnet portion. With this type of magnet assembly, there is no need to place a magnetic shield between the magnet units to suppress mutual interference of adjacent magnetic poles. Therefore, the size of the magnet assembly can be further reduced.

The present invention is not limited to the above embodiment, but the following modifications can be made. (1) The dimensions, materials, numbers, etc. of the magnet assembly and the magnet units included therein in each of the above-described embodiments are not limited to these, and can be arbitrarily changed without departing from the scope of the present invention. Is. (2) The moving mechanism of the magnet assembly in FIG. 18 uses a combination of the eccentric cam and the guide hole, but a moving mechanism other than this can be adopted. (3) In each of the above-described embodiments, the magnetic pole arrangement of the magnet unit is such that the target-side magnetic pole surface of the central magnet is the S pole and the target-side magnetic pole surface of the peripheral magnet is the N pole. However, the magnetic pole arrangement opposite to this may be adopted. That is, the magnetic pole arrangement of all magnet units is
The target-side magnetic pole surface of the central magnet can be the N pole, and the target-side magnetic pole surface of the peripheral magnet can be the S pole.

[0078]

The feature common to all of the present invention is that the magnetic field produced by the magnet units at both ends on the target surface is stronger than that on the inner side. Has the common effect of improving the film thickness distribution.

According to the invention of claim 1, in addition to the above-mentioned common effect, since the magnetic shield is arranged between the magnet units,
The magnetic fields of the magnet units do not cancel each other out, and uneven distribution of magnetic fields due to mutual interference of magnetic fields is prevented.

According to the invention of claim 4, in addition to the common effect described above, the magnetic field uniformity within a single magnet unit is within ± 5%, and the magnetic field homogeneity within a magnet unit is within ± 5%. Therefore, uneven distribution and instability of discharge are eliminated, and the film thickness distribution on the substrate is improved.

In addition to the common effects described above, the invention of claim 5 reciprocates the magnet assembly composed of a plurality of magnet units, so that the film thickness distribution can be further improved and the target utilization efficiency can be improved. Can be improved, and particles generated due to the deposited film on the target surface can be suppressed.

According to the invention of claim 8, in addition to the above-mentioned common effect, it is not necessary to dispose a magnetic shield for suppressing mutual interference of adjacent magnetic poles between the magnet units, and the magnet assembly can be made smaller. it can.

[Brief description of drawings]

FIG. 1 is a front cross-sectional view of the overall configuration of a sputtering apparatus to which the present invention is applied.

FIG. 2 is a front sectional view of a deep cathode electrode related to the present invention.

3 is a plan view of a magnet assembly of the cathode electrode of FIG.

FIG. 4 is a cross-sectional view of the cathode electrode magnet unit of FIG. 2;
It is a top view and a perspective view.

FIG. 5 is a plan view showing a movement trajectory of drift electrons and a cross-sectional view of a corresponding magnet assembly.

FIG. 6 is a cross-sectional view showing lines of magnetic force generated by the magnet assembly.

FIG. 7 is a front sectional view of another cathode electrode which is closely related to the present invention.

8 is a sectional view taken along line VIII-VIII of FIG.

9A and 9B are a plan view and a cross-sectional view showing an erosion region on a target.

FIG. 10 is a plan view showing a modification of the magnetic shield of the magnet assembly.

FIG. 11 is a plan view showing another modification of the magnetic shield of the magnet assembly.

FIG. 12 is a plan view showing still another modification of the magnetic shield of the magnet assembly.

FIG. 13 is a front sectional view of a cathode electrode according to an embodiment of the present invention.

FIG. 14 is a cross-sectional view showing three arrangement examples of magnet units.

FIG. 15 is a graph showing a film thickness distribution of a thin film manufactured by using the arrangement of FIG.

FIG. 16 is a graph showing a film thickness distribution of a thin film manufactured with a step of 5 mm in the arrangement of FIG. 14C.

FIG. 17 is a graph showing a film thickness distribution of a thin film manufactured with the arrangement shown in FIG. 14C and a step difference of 3 mm.

FIG. 18 is a front sectional view of a cathode electrode according to another embodiment of the present invention.

FIG. 19 is a perspective view of another type of magnet unit and a sectional view of a magnet assembly using the same.

FIG. 20 is a diagram for explaining the magnetic field uniformity of the magnet unit.

[Explanation of symbols]

 22 target assembly 31 electrode housing 43 yoke 48 magnet fixing pedestal 49 magnetic shield 74A, 74B magnet unit 75 spacer

Front Page Continuation (72) Inventor Naoyoshi Hosokawa 5-8-1 Yotsuya, Fuchu-shi, Tokyo Within Anelva Co., Ltd.

Claims (9)

[Claims] 1. A vacuum container provided with an exhaust system for evacuating the interior, a substrate holding member disposed inside the vacuum container for mounting a substrate to be subjected to film formation processing, and a position facing the substrate. At least one magnetron cathode electrode having a rectangular planar target for forming a film on the substrate, and gas control for circulating a gas inside the vacuum container to appropriately maintain the internal pressure. A sputtering apparatus including a system and a power supply system for supplying electric power to the magnetron cathode electrode, the sputtering apparatus having the following features. (A) The magnetron cathode electrode includes a plurality of magnet units on the back surface of one rectangular planar target. (B) The magnet unit has a rectangular cross section parallel to the target surface, and a plurality of magnet units are arranged such that a long side is adjacent to a long side of an adjacent magnet unit. (C) The magnetic poles of the magnet units are the same in all the magnet units included in the same magnetron cathode electrode. (D) The magnet unit has a structure that causes an annular electron drift motion locus on the surface of the target. (E) Among the plurality of magnet units, the strength of the magnetic field generated on the target surface by the two magnet units at both ends in the short side direction of the magnet unit is equal to the magnetic field generated on the target surface by the magnet units inside thereof. Greater than strength. (F) The magnetic shield wall is arranged between the adjacent magnet units. 2. The sputtering apparatus according to claim 1, wherein the height of the magnet portions of the magnet units on both sides is larger than the height of the magnet portions of the inner magnet units. 3. The sputtering apparatus according to claim 1, wherein the plurality of magnet units have a magnetic field uniformity within ± 5% within a single magnet unit, and ± 5 between the two magnet units on both sides. % Magnetic field homogeneity, and the inner magnet units have magnetic field homogeneity within ± 5%. 4. A vacuum container provided with an exhaust system for bringing the inside into a vacuum state, a substrate holding member arranged inside the vacuum container for mounting a substrate to be subjected to film formation processing, and a position facing the substrate. At least one magnetron cathode electrode having a rectangular planar target for forming a film on the substrate, and gas control for circulating a gas inside the vacuum container to appropriately maintain the internal pressure. A sputtering apparatus including a system and a power supply system for supplying electric power to the magnetron cathode electrode, the sputtering apparatus having the following features. (A) The magnetron cathode electrode includes a plurality of magnet units on the back surface of one rectangular planar target. (B) The magnet unit has a rectangular cross section parallel to the target surface, and a plurality of magnet units are arranged such that a long side is adjacent to a long side of an adjacent magnet unit. (C) The magnetic poles of the magnet units are the same in all the magnet units included in the same magnetron cathode electrode. (D) The magnet unit has a structure that causes an annular electron drift motion locus on the surface of the target. (E) Among the plurality of magnet units, the strength of the magnetic field generated on the target surface by the two magnet units at both ends in the short side direction of the magnet unit is equal to the magnetic field generated on the target surface by the magnet units inside thereof. Greater than strength. (F) The plurality of magnet units have magnetic field homogeneity within ± 5% within a single magnet unit, and magnetic field homogeneity within ± 5% between the two magnet units on both sides, The inner magnet units have magnetic field uniformity within ± 5%. 5. The sputtering apparatus according to claim 4, wherein the magnet unit is capable of reciprocating in the direction of the short side of the rectangle. 6. A vacuum container provided with an exhaust system for evacuating the interior, a substrate holding member for mounting a substrate to be subjected to a film formation process, which is disposed inside the vacuum container, and a position facing the substrate. At least one magnetron cathode electrode having a rectangular planar target for forming a film on the substrate, and gas control for circulating a gas inside the vacuum container to appropriately maintain the internal pressure. A sputtering apparatus including a system and a power supply system for supplying electric power to the magnetron cathode electrode, the sputtering apparatus having the following features. (A) The magnetron cathode electrode includes a plurality of magnet units on the back surface of one rectangular planar target. (B) The magnet unit has a rectangular cross section parallel to the target surface, and a plurality of magnet units are arranged such that a long side is adjacent to a long side of an adjacent magnet unit. (C) The magnetic poles of the magnet units are the same in all the magnet units included in the same magnetron cathode electrode. (D) The magnet unit has a structure that causes an annular electron drift motion locus on the surface of the target. (E) Among the plurality of magnet units, the strength of the magnetic field generated on the target surface by the two magnet units at both ends in the short side direction of the magnet unit is equal to the magnetic field generated on the target surface by the magnet units inside thereof. Greater than strength. (F) The distance from the target-side magnetic pole surface of the both magnet units to the target surface is smaller than the distance from the target-side magnetic pole surface of the inner magnet unit to the target surface. 7. The sputtering apparatus according to claim 1, wherein the magnet unit includes a yoke, a central magnet fixed on the yoke, and a magnet fixed on the yoke. It is composed of a peripheral magnet surrounding the central magnet, and the central magnet and the peripheral magnet have magnetic pole surfaces on the surface fixed to the yoke and the surface on the target side, and the magnetic pole on the target side of the central magnet and the target side of the peripheral magnet. And a magnetic pole having a polarity opposite to each other. 8. A vacuum container provided with an exhaust system for evacuating the interior, a substrate holding member disposed inside the vacuum container for mounting a substrate to be subjected to film formation processing, and a position facing the substrate. At least one magnetron cathode electrode having a rectangular planar target for forming a film on the substrate, and gas control for circulating a gas inside the vacuum container to appropriately maintain the internal pressure. A sputtering apparatus including a system and a power supply system for supplying electric power to the magnetron cathode electrode, the sputtering apparatus having the following features. (A) The magnetron cathode electrode includes a plurality of magnet units on the back surface of one rectangular planar target. (B) The magnet unit has a rectangular cross section parallel to the target surface, and a plurality of magnet units are arranged such that a long side is adjacent to a long side of an adjacent magnet unit. (C) The magnetic poles of the magnet units are arranged such that the adjacent magnet units have opposite polarities. (D) The magnet unit has a structure that causes an annular electron drift motion locus on the surface of the target. (E) Among the plurality of magnet units, the strength of the magnetic field generated on the target surface by the two magnet units at both ends in the short side direction of the magnet unit is equal to the magnetic field generated on the target surface by the magnet units inside thereof. Greater than strength. 9. The sputtering apparatus according to claim 8, wherein the magnet unit is composed of a frame-shaped rectangular magnet without a central magnet, and has a magnetic pole surface perpendicular to the target surface. .