JP2006283057A - Sputtering apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moving machine capable of performing scan in a short period of time with small power consumption during hand-over. <P>SOLUTION: A sputtering apparatus 10 includes a substrate supporting part 18, a target 20 and magnets 22 which are arranged in a vacuum container 12. A flat target 20 is arranged facing a substrate W. A plurality of magnets 22 are arranged facing a surface opposite from a substrate W-opposing surface of the target 20. The outline of each magnet 22 is square in the face facing the target 20. Thus, the distance of accelerating drift electrons 30 becomes the same, and non-uniformity in the speed of the electrons 30 hardly occurs. Thus, the sputtering degree of the target 20 is also uniform and the film deposition can also be performed uniformly. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sputtering apparatus.

In a sputtering apparatus, it is important to form a uniform film on the entire surface of a larger substrate. When a film is formed on a square substrate by sputtering, the thin film formed on the square substrate tends to be non-uniform. Therefore, as an attempt to make the film formation uniform, Patent Document 1 proposes a sputtering apparatus in which a target that is square and divided into a rectangular shape and a magnet are arranged on a substrate on which film formation is performed. Furthermore, Patent Document 1 also describes a sputtering apparatus in which magnets are arranged in an annular shape on the back surface of a target.
Japanese Patent Laid-Open No. 9-13169

  However, in such a sputtering apparatus, there is a difference in plasma density on the target, resulting in non-uniform film formation on the substrate. In particular, when the substrate is rectangular and the aspect ratio (aspect ratio) of the rectangle is large, the tendency is remarkable.

  This invention is made | formed in view of this situation, The objective is to provide the sputtering device which can form into a film uniformly with a board | substrate.

  In the present invention, the flat target disposed in the vacuum container, the substrate support part disposed in the vacuum container and supporting the substrate, and the substrate disposed in the vacuum container and opposed to the substrate supported by the substrate support part. And a plurality of magnets arranged to face the surface opposite to the surface facing the substrate of the target, each of the plurality of magnets having an aspect ratio of 0.5 to 0.5 on the surface facing the target 2 is provided.

  In this configuration, in each of the plurality of magnets, the aspect ratio of the surface facing the target is 0.5 to 2, so that the electron drift motion on the target becomes uniform, and the substrate is more uniformly deposited. Can do. In the present invention, “the aspect ratio of the surface facing the target is 0.5 to 2” means that the aspect ratio of the rectangle circumscribing the outline of each magnet is 0.5 to 2 in the surface facing the target. 2 means. Therefore, in the rectangular magnet, the ratio of the length of the long side to the short side corresponds to the aspect ratio in the present invention. In a square magnet, the aspect ratio is 1 because the length of each side is the same. In a circular magnet, the length of the circumscribed rectangle is equal to the length of the short side, so the aspect ratio is 1. In the elliptical magnet, the aspect ratio of the circumscribed rectangle corresponds to the ratio of the length of the major axis to the minor axis, so the ratio of the length of the major axis to the minor axis corresponds to the aspect ratio in the present invention. In the triangular, hexagonal and other polygonal magnets, the aspect ratio of the circumscribed rectangle corresponds to the aspect ratio in the present invention.

  In this case, it is official that each of the plurality of magnets is circular on the surface facing the target.

  According to this configuration, since each of the plurality of magnets is circular on the surface facing the target, the drift movement of electrons on the target is smoother than that of a square magnet, and the film is more uniformly formed on the substrate. Can be applied. The “circular shape” in the present invention is not limited to a perfect circle but includes an ellipse.

  In this case, it is preferable that each of the plurality of magnets is capable of changing the distance from the substrate supported by the substrate support portion.

  According to this configuration, since the distance between each of the plurality of magnets and the substrate supported by the substrate support portion can be freely changed, by adjusting the distance between the magnet and the substrate or the distance between the magnet and the target, The sputtering rate and the film formation rate can be controlled, and the film can be formed more uniformly on the substrate.

  In this case, it is preferable that each of the plurality of magnets be movable in parallel to the surface of the substrate supported by the substrate support portion. According to this configuration, the film formation can be made more uniform.

  In this case, it is preferable that the plurality of magnets are arranged in a staggered manner. According to this configuration, the utilization efficiency of the target is improved.

  According to the sputtering apparatus of the present invention, the drift motion of electrons on the target becomes uniform, and film formation can be performed more uniformly on the substrate.

  Hereinafter, a sputtering apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a longitudinal sectional view showing a configuration of a sputtering apparatus according to the first embodiment of the present invention. As shown in FIG. 1, in the sputtering apparatus 10 of the present embodiment, a substrate support unit 18 that supports a substrate W, a target 20, and a magnet 22 are arranged in a vacuum vessel 12.

  Connected to the vacuum vessel 12 are an exhaust system 14 capable of exhausting the air in the vacuum vessel 12 to reduce the pressure, and an introduction system 16 for introducing an inert gas such as Ar into the vacuum vessel 12. A substrate support 18 that supports the substrate W is provided on the upper wall surface of the vacuum vessel 12.

  In the vacuum vessel 12, a flat target 20 is provided so as to face the substrate W supported by the substrate support 18. The target 20 serves as a sputtering source, and the target 20 can be made of an insulating material in addition to a metal such as Al.

  A plurality of magnets 22 are arranged facing the surface opposite to the surface facing the substrate W of the target 20. FIG. 2 is a plan view showing the arrangement of targets and magnets according to the first embodiment of the present invention. In the following FIGS. 2, 6, 8 and 9, the magnet 22 is seen from the substrate W and the target 20 side. The outer and inner magnets in one magnet 22 shown in FIG. 2 are magnets having different polarities. As shown in FIG. 2, each of the magnets 22 has a square shape on the surface facing the target 20. In this embodiment, the aspect ratio V / H, which is the ratio of the length V in the vertical direction and the length H in the horizontal direction on the outer surface of the magnet 22 facing the target 20, is 0.5-2. More preferably, it is 0.8-1.2, More preferably, it is 0.9-1.1, Most preferably, it is set to 1 as shown in FIG.

  Returning to FIG. 1, the plurality of magnets 22 are supported on the vacuum vessel 12 by ball screws 26. The ball screw 26 is provided with a ball screw driving unit 28, and the distance between each magnet 22 and the substrate W supported by the substrate supporting unit 18 can be changed. An airtight bellows 24 is provided around each ball screw 26 so that the periphery of the ball screw 26 is airtight. The target 20 is connected to a power source (not shown).

  Hereinafter, the operation of the sputtering apparatus of this embodiment will be described. The substrate W on which the film is to be formed is fixed on the substrate support 18, the air in the vacuum vessel 12 is exhausted and decompressed by the exhaust system 14, and then Ar gas is introduced from the introduction system 16 at a predetermined pressure. Next, when power is applied to the target 20 from a power source (not shown), Ar gas molecules are turned into plasma. Here, electrons are trapped by each magnet 22 and drift on the target 20.

  FIG. 3 is a diagram showing a trajectory of electrons drifting on a conventional target. As shown by a broken line in FIG. 3, in the conventional sputtering apparatus in which the aspect ratio V / H of the magnet is approximately 3 or more, the electrons 30 drifting on the target 20 are accelerated at the positions of the short sides of the magnet 22. Since the distance to be applied is short, the speed is slow, and at the position of the long side of the magnet 22, the speed at which the electrons 30 are accelerated tends to be high because the distance to be accelerated is long. For this reason, the degree to which the target 20 is sputtered becomes non-uniform and the film formation becomes non-uniform. In particular, this tendency increases when the aspect ratio of the magnet or the target is increased in accordance with a substrate having a large aspect ratio.

  On the other hand, in the present embodiment, as shown by the broken line in FIG. 4, since the aspect ratio V / H of the magnet 22 is close to 1, the distance at which the electrons 30 drifting on each side are accelerated becomes the same. Unevenness is unlikely to occur at the speed of 30. Therefore, the degree to which the target 20 is sputtered becomes uniform, and film formation can be performed more uniformly.

  In addition, as shown in FIG. 5, the sputter rate at each position of the target 20 is changed by changing the distance between each magnet 22 and the target 20 and the substrate W by each ball screw driving unit 28. By adjusting the film formation speed at each position of the substrate W, more uniform film formation is possible. In addition, by making each magnet 22 movable not in a direction perpendicular to the surface of the substrate W as shown in FIG. 5 but in a direction parallel to the surface of the substrate W, adjustment with a higher degree of freedom becomes possible. . For this reason, the film can be made more uniform, and the target can be used without being biased. Therefore, the utilization efficiency of the target is improved, which is effective.

  Hereinafter, a second embodiment of the present invention will be described. FIG. 6 is a plan view showing the arrangement of targets and magnets according to the second embodiment of the present invention. As shown in FIG. 6, in this embodiment, each magnet 22 is different from the first embodiment in that the outer shape of each magnet 22 forms a perfect circle on the surface facing the target 20.

  When film formation is performed by the sputtering apparatus of the present embodiment, the electrons 30 drifting on the circular target 20 are drifted in a uniform arc as shown by the broken line in FIG. In this case, since there is no corner portion in the magnet 22 as in the first embodiment, the drift movement of electrons on the target 20 becomes smoother, and more uniform and stable sputtering and film formation are possible.

  FIG. 8 is a plan view showing the arrangement of targets and magnets according to the third embodiment of the present invention. In this embodiment, the square magnets 22 and the targets 20 are arranged in a staggered manner. Thereby, since the utilization efficiency of the target is improved, more uniform sputtering is possible, and the film formation is also uniform. It should be noted that the same effect can be achieved when a regular triangle or regular hexagonal magnet is used and arranged in a staggered manner with the sides of each magnet in close contact.

  FIG. 9 is a plan view showing the arrangement of targets and magnets according to the fourth embodiment of the present invention. As shown in FIG. 9, more uniform sputtering and film formation are possible by arranging the circular magnets 22 in a staggered manner, and more preferably arranging the magnets 22 so as to be contained most densely per unit area. It becomes.

  FIG. 10 is a longitudinal sectional view showing the configuration of the sputtering apparatus according to the fifth embodiment of the present invention. The present embodiment is different from the first to fourth embodiments in that the target 20 is divided corresponding to the shape of the magnet 22 and is fixed to each magnet 22. In addition, about the shape and other structure of the magnet 22, the thing of 1st-4th embodiment is applicable as it is.

  In the present embodiment, when it is desired to adjust the degree of film formation at each position on the substrate W, the distance between each magnet 22 and target 20 and the substrate W is changed by the ball screw driving unit 28 as shown in FIG. By doing so, the film-forming speed | rate in each position of the board | substrate W can be changed. In addition, by making each magnet 22 and target 20 movable in a direction parallel to the surface of the substrate W, not in a direction perpendicular to the surface of the substrate W as shown in FIG. Is possible.

  Note that the sputtering apparatus of the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the scope of the present invention.

It is a longitudinal section showing the composition of the sputtering device concerning a 1st embodiment of the present invention. It is a top view which shows arrangement | positioning of the magnet which concerns on 1st Embodiment of this invention. It is the figure which showed the locus | trajectory of the electron which drifts on the conventional target. It is the figure which showed the locus | trajectory of the electron which drifts on the target which concerns on 1st Embodiment of this invention. It is the figure which showed a mode that the magnet which concerns on 1st Embodiment of this invention changes the distance with a board | substrate. It is a top view which shows arrangement | positioning of the magnet which concerns on 2nd Embodiment of this invention. It is the figure which showed the locus | trajectory of the electron which drifts on the target which concerns on 2nd Embodiment of this invention. It is a top view which shows arrangement | positioning of the target and magnet which concern on 3rd Embodiment of this invention. It is a top view which shows arrangement | positioning of the target and magnet which concern on 4th Embodiment of this invention. It is a longitudinal cross-sectional view which shows the structure of the sputtering device which concerns on 5th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Sputtering device, 12 ... Vacuum container, 14 ... Exhaust system, 16 ... Introduction system, 18 ... Substrate support part, 20 ... Target, 22 ... Magnet, 24 ... Bellows, 26 ... Ball screw, 28 ... Ball screw drive part, 30 ... Electronic, W ... Board

Claims (5)

A vacuum vessel;
A substrate support part disposed in the vacuum vessel and supporting the substrate;
A flat target disposed in the vacuum vessel and disposed opposite the substrate supported by the substrate support;
A plurality of magnets disposed opposite to the surface opposite to the surface facing the substrate of the target;
With
Each of the plurality of magnets has an aspect ratio of 0.5 to 2 on a surface facing the target.
Sputtering equipment. Each of the plurality of magnets is circular on the surface facing the target.
The sputtering apparatus according to claim 1. Each of the plurality of magnets is capable of changing the distance from the substrate supported by the substrate support portion.
The sputtering apparatus according to claim 1 or 2. Each of the plurality of magnets is movable in parallel to the surface of the substrate supported by the substrate support portion.
The sputtering apparatus according to any one of claims 1 to 3. The plurality of magnets are arranged in a staggered manner,
The sputtering apparatus of any one of Claims 1 thru | or 4.

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