JP2003183828A - Magnetron sputtering method with multiplex magnetic poles - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the life of a target and the utilization efficiency in a magnetron sputtering method. <P>SOLUTION: This magnetron sputtering method comprises forming a magnetic field P formed on a front face 7a of a tabular target 7 by magnetic-field- generating means 1 and 2 arranged in a back face 7b of the target to form an erosion region, sputtering the target with plasma generated in the erosion region, and making the generated sputtered particles reach a substrate 8 arranged so as to face with the target 7 and form a thin film 8a. A magnetron sputtering apparatus radially has several supplemental magnetic-field-generating means 3 which have the magnetic poles having different polarities from those of the back central magnetic poles 1a, so as to direct toward the center of the target 7 in the circumferential outer side of the sputtering side 7a of the target 7. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a magnetron sputtering method for forming a magnetic thin film on a substrate, and more particularly to a magnetron sputtering method using a target made of a magnetic material.

[0002]

2. Description of the Related Art FIG. 1 shows the structure of a conventional magnetron sputtering method, which is composed of a flat target 7 and magnetic field generating means 1 and 2 arranged on the back surface thereof.
In this magnetron sputtering method, magnetic field generating means 1 and 2 are provided on the back surface 7b side (non-sputtering surface side) of the target 7, and the magnetic field lines Q cause a magnetic field P near the sputtering surface 7a.
To increase the frequency of collision of electrons with the rare gas 22 such as argon gas introduced into the vacuum chamber 21 to dramatically improve the ionization of the atmospheric gas, thereby forming a plasma having a high ion density. Magnetron sputtering for sputtering is known.

There is also proposed a method of providing a plurality of auxiliary magnetic field generating means 3 on the outer peripheral portion as shown in FIGS. 2 and 3. 2 and 3 have a configuration in which the magnetron structure of FIG. 1 has a plurality of sets of auxiliary magnetic field generating means 3 in which magnets 3a to 3n adjacent to each other are alternately arranged on the outer peripheral portion of the front surface of the target 7.

[0004]

In the magnetron sputtering method, it is required to improve the film quality of the generated film 8a, the film forming speed, and the utilization efficiency of the target 7. In the present invention, since the magnetic field is generally difficult to pass through, the deposition rate is slow on the surface of the substrate 8 and the target 7
The object is to improve the operation efficiency as a device aiming at improving the practical life of the target 7 and the utilization efficiency by solving the drawback that the frequency of replacement is high because the utilization area of the target is small and the thickness D cannot be increased. .

[0005]

Means for Solving the Problem An explanation will be given with reference to FIGS. 4 to 5. In the multi-pole magnetron sputtering method according to the invention of claim 1, the magnetic field generating means 1 and 2 provided on the back surface 7b of the flat plate type target 7 causes the front surface 7 of the target.
The magnetic field P applied to a forms an erosion region, the plasma generated in the erosion region performs sputtering, and the generated sputtered particles reach the substrate 8 arranged facing the target 7, thereby manufacturing the thin film 8a. The target 7 is made of a magnetic material E, and the target 7 has a sputtering surface 7a side.
Auxiliary magnetic field generating means 3 in a state in which a magnetic pole having a different pole from the back center magnetic pole 1 is directed to the center of the target 7 outside the periphery of the target 7.
By providing a plurality of radials, the magnetic fields R and T applied by the auxiliary magnetic field generating means 3 and the magnetic pole generating means 1 and 2, respectively, and the composite magnetic field formed by the interaction of these magnetic field generating means are used. It is characterized by forming an erosion region.

In the magnetron sputtering method according to the second aspect of the present invention, as shown in FIG. 6, a plurality of auxiliary magnetic field generating means 3 and 4 are provided in the direction of the target front surface 7a in the first aspect of the invention.
It is characterized by arranging them and making each stage the same pole.

[0007]

DETAILED DESCRIPTION OF THE INVENTION A magnetron sputtering apparatus applied to a magnetron sputtering method according to an embodiment of the present invention will be described with reference to FIGS. 4 to 5. The outer peripheral magnets 2a to 2n on the target back surface 7b are arranged with the N poles facing the target back surface 7b, and the central magnet 1a arranged at the center of the target back surface 7b is arranged with the S pole facing the target back surface 7b. , Target back magnet 1
a, the yoke 11 placed further on the back side of the target back surface outer peripheral magnets 2a to 2n constitutes a closed circuit of magnetic force, and part of the magnetic force line R from the target back surface outer peripheral magnets 2a to 2n to the target back surface 7b is the magnetic material E. Although it is absorbed inside the target 7 formed in the above, a part of the light penetrates the target 7, passes through the target surface 7a, and enters the S pole of the central magnet 1a.

The target front outer peripheral magnets 3a to 3n arranged radially on the outer peripheral portion of the target front have an N pole directed toward the center, and the magnetic force T generated from this magnet is attracted and incident on the S pole of the target rear central magnet 1a. , Part of it tries to build a self-circuit by turning in the direction opposite to the direction of the target front surface 7a. At this time, since the target front outer peripheral magnets 3a to 3n and the target rear outer peripheral magnets 2a to 2n have the same polarity, they repel each other and the magnetic force lines R from the target rear outer peripheral magnets 2a to 2n to the target rear central magnet 1a are pressed to the vicinity of the target surface 7a. To be acted upon. Due to these interactions, the magnetic field line density in the vicinity of the target surface 7a can be considerably increased, and the region of plasma density effective for sputtering is also widened. As a result, a high-density plasma is generated and high-speed sputtering is performed toward the substrate 8. Further, the erosion area of the target 7 is expanded and the utilization efficiency of the target is improved.

FIG. 6 shows an embodiment of the invention of claim 2,
In FIG. 6, the target front outer peripheral upper magnets 4a to 4n added to FIG. 4 have an effect of pushing down the magnetic force lines escaping to the substrate 8 side of the target front outer peripheral magnets 3a to 3n which are the lower side, and are more effective than those in FIGS. High density plasma can be obtained.

In the above description, the target front surface 7
Although the magnets 3a to 3n and 4a to 4n in the outer peripheral portion are all configured to have the same poles, the same applies to the case where the front and rear magnets are configured to have the same poles as shown in FIGS. 7 to 9. Is.

According to the first aspect of the present invention, the magnetic force T generated from the front outer peripheral magnets 3a to 3n of the target is incident on the rear central magnet 1a which is a counter electrode to form a magnetic field circuit. Further, the magnetic force lines R passing through the target 7 from the target back surface outer peripheral magnets 2a to 2n toward the back surface center magnet 1a are also compressed into the magnetic force lines T from the front surface outer peripheral magnets 3a to 3n and distributed at high density on the target surface 7a. Has the effect of being able to.

According to the invention of claim 2, the auxiliary magnetic field generating means is a magnetron sputtering method characterized in that a plurality of steps are arranged in the direction of the front surface 7a of the target and each step has the same pole. Front peripheral magnets 3a-3
Of the magnetic force lines T emerging from n, the magnetic force lines emitted from the front direction escape to the front direction to form a circuit with its own counter electrode. By arranging a magnet of the same pole on the front surface, it is possible to guide the magnet toward the center of the target by utilizing mutual repulsive forces.

[0013]

Embodiments will be described with reference to FIGS. 10 to 21.
11 to 21, since all the magnets are symmetrically arranged in a disk shape, the magnetic force diagrams are all 1/4 of the disk surface.
The magnetic field lines in the region of are measured and illustrated.

FIG. 10 is a diagram showing the arrangement of magnets on the back surface of the target 7.

FIG. 11 shows the state of FIG. 1 before attaching the target 7.
It can be seen that the line of magnetic force on the surface of 0 is sufficient for the line of magnetic force.

FIG. 12 is a magnetic force line diagram showing a state in which a nickel plate having a thickness of 5 mm is attached as the target 7, and it can be seen that the number has decreased.

FIG. 13 shows the front outer peripheral magnets 3a to 3 shown in FIG.
It can be seen that the magnetic field lines from the front outer peripheral magnets 3a to 3n slightly overlap with the magnetic field lines from the back surface in the figure in which n is arranged in one stage, but the magnetic force from the front surface outer surface has almost escaped to the front surface.

FIG. 14 is a magnetic force line diagram in which the second outermost front outer peripheral magnets 4a to 4n of the same pole are arranged in FIG. 13, and most of the magnetic force lines from the side face which escaped to the front face in FIG. You can see that it extends to.

FIG. 15 shows the front outer peripheral magnets 3a to 3n as NS.
The distribution of the magnetic field lines from N to S of the front outer peripheral magnets 3a to 3n can be seen in the case where they are alternated.

FIG. 16 is a diagram in which a front outer peripheral upper stage magnet is added to FIG. 15 to have two stages of the same pole, and the magnetic field lines between NS are pushed toward the target 7 and the component parallel to the plane increases. I understand.

In FIG. 17, the target 7 is a nickel plate 8 m.
It can be seen from the diagram of the surface magnetic force lines when m is set, which is considerably smaller than that in FIG.

FIG. 18 shows the front outer peripheral magnets 3a to 3 shown in FIG.
In the diagram in which n1 stages are arranged, the attraction at the center is weak, and the magnetic force lines of the front peripheral magnets 3a to 3n almost escape to the front.

FIG. 19 shows the front peripheral magnets 4a to 4 shown in FIG.
In the figure in which n is added and two poles of the same pole are provided, front outer peripheral magnets 3a to 3
It can be clearly seen that the magnetic force of n is extended to the center by the magnetic force of the front outer peripheral upper magnets 4a to 4n being pressed down, and this figure is the figure in which the effect of making two steps is the most effective.

FIG. 20 is a magnetic force diagram of an 8 mm target in which the front outer peripheral magnets are alternately NS.

FIG. 21 is a front outer peripheral upper stage magnet 4a shown in FIG.
It can be seen that the components parallel to the target 7 are increased in comparison with FIG.

[0026]

According to the present invention, the target surface 7a
High density and wide range magnetic field concentration can be performed in the vicinity, high density plasma can be generated here, high speed film formation can be performed, erosion area can be expanded, and target plate thickness D can be increased. The advantageous effect that a sputtering apparatus for a magnetic material material having a high production efficiency can be produced comprehensively can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic front view of a conventional example.

FIG. 2 is a schematic front view of another conventional example.

FIG. 3 is a plan view of FIG.

FIG. 4 is a schematic front view of an example of the present invention.

FIG. 5 is a plan view of FIG.

FIG. 6 is a schematic front view of another example of the present invention.

FIG. 7 is a schematic plan view of an application example.

FIG. 8 is a front view taken along line XX of FIG. 7.

9 is a side view taken along the line YY of FIG. 7.

FIG. 10 is an arrangement view of magnets on the back surface of the target.

FIG. 11 is a state of magnetic lines of force on the surface of FIG. 10 before attaching a target.

FIG. 12 is a magnetic line diagram in which a thin nickel plate is attached as a target.

FIG. 13 is a diagram showing a front peripheral magnet arranged in one stage in FIG.

FIG. 14 is a magnetic force line diagram in which a front outer peripheral upper magnet of the same pole of the second step is further arranged in FIG.

FIG. 15 is a diagram showing a case where front outer peripheral magnets are alternated with NS.

FIG. 16 is a view in which a front outer peripheral upper stage magnet is added to FIG. 15 to form two stages of the same pole.

FIG. 17 is a diagram of the surface magnetic force lines when the target is a thick nickel plate.

FIG. 18 is a view in which one front outer peripheral magnet is arranged in FIG.

FIG. 19: A front outer circumference upper magnet is added to FIG.
FIG.

FIG. 20 is a magnetic force line diagram of a nickel thick plate target when the front outer peripheral magnets are alternated with NS.

FIG. 21 is a diagram in which a front outer peripheral upper stage magnet is added to FIG. 20 and a second stage magnet having the same pole is arranged.

[Explanation of symbols]

1 Magnetic field generating means 1a Target center back magnet 2 Magnetic field generating means 2a ~ 2n Target back peripheral magnet 3 Auxiliary magnetic field generating means 3a to 3n Target front peripheral magnet 4a-4n Target front outer circumference upper magnet 7 target 7a Target front 7b Target rear surface 8 substrates 8a thin film 11 York 21 vacuum chamber 22 Noble gas D thickness E magnetic material P magnetic field Q 2a to 2n → 10 Magnetic field lines T 3a to 3n → 10 Magnetic field lines

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor, Wataru Watanabe             1-21-35, Kusatsushinmachi, Nishi-ku, Hiroshima-shi, Hiroshima             Asahi Works Hiroshima Sales Office (72) Inventor Osamu Fujii             5-28-23 Hikino-cho, Fukuyama City, Hiroshima Prefecture F-term (reference) 4K029 BA12 CA05 DC03 DC43                 5D112 FA04

Claims (2)

[Claims] 1. A back surface (7b) of a flat plate target (7).
The magnetic field (P) applied to the target front surface (7a) forms an erosion region by the magnetic field generation means (1, 2) provided in the, and sputtering is performed by the plasma generated in the erosion region. A magnetron sputtering method for forming a thin film (8a) by making particles reach a substrate (8) arranged facing a target (7). The target (7) is composed of a magnetic material (E), and A state in which a magnetic pole having a pole different from that of the back center magnetic pole (1) is directed toward the center of the target (7) on the sputtering surface (7a) side of the target (7) and outside the peripheral edge of the target (7). By providing a plurality of auxiliary magnetic field generating means (3) radially, the auxiliary magnetic field generating means (3) and the magnetic pole generating means (1, 2) are applied respectively. The magnetic field (R, T) which, multi-polar magnetron sputtering method and forming the erosion area by a composite magnetic field formed by the interaction of these magnetic field generating means. 2. The multi-pole magnetron sputtering method according to claim 1, wherein the auxiliary magnetic field generating means are arranged in a plurality of steps (3, 4) in the direction of the front surface (7a) of the target, and each step has the same pole. .