JP2008280550A - Opposing target sputtering apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an opposing target sputtering apparatus capble of improving production yield. <P>SOLUTION: The opposing target sputtering apparatus is equipped with: a vacuum tank capable of being maintained in a vacuum state; a substrate holder which is arranged in the vacuum tank and on which substrates are mounted; target holders for each placing a target provided opposite to the substrate holder thereon; magnets which are each arranged on the opposite side of the surface for placing the target thereon of the target holder; a sputtering power source for applying a direct current power source to each target holder; and a gas supply and exhaust means for introducing a gas into the vacuum tank or exhausting the gas, wherein each magnet has a rectangular-ring shape and the central axis in the longitudinal direction of each magnet is inclined with respect to the central axis in the longitudinal direction of each target holder. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an opposed target sputtering apparatus and method capable of producing a uniform thin film on a substrate at a low temperature.

  Opposite target sputtering is used for forming a thin film on a resin film or the like because a sputtered film can be formed at a low temperature (for example, Patent Documents 1, 2, and 3). In recent years, research has been conducted on the use of a resin film as a substrate material for display devices and optical components using organic EL, and opposed target sputtering has been studied for its production.

  Hereinafter, an example of a conventional counter target sputtering apparatus will be described with reference to FIG. A pair of targets 2 and 3 are disposed in the vacuum chamber 1 so as to face each other in parallel with a space therebetween, and the substrate 4 is disposed on a substrate holder 5 provided on the side of the targets 2 and 3. The target holders 6 and 7 have a hollow structure, are provided with cooling water supply pipes 8a and 9a, and discharge pipes 8b and 9b so as to be cooled, and are installed in the vacuum chamber 1 through insulating members 10 and 11.

  On the other hand, the magnetic field generating means is the permanent magnets 12 and 13, and at the same time, the magnetic fields formed by the magnetic poles in the target holders 6 and 7 behind the targets 2 and 3 are all perpendicular to the sputtering surfaces of the targets 2 and 3. They are arranged in the same direction and around the targets 2 and 3. Therefore, the magnetic field is formed only in the space between the targets 2 and 3. Reference numerals 14 and 15 are shields for protection.

  Therefore, after evacuating the inside of the vacuum chamber 1 through the exhaust port 16 by an exhaust system (not shown), a sputtering gas such as argon is introduced from the gas introduction system (not shown) through the introduction port 17, and the sputtering consisting of a direct current power source. Sputtering is performed by supplying the sputtering power by the power source 18 with the shields 14 and 15 and the vacuum chamber 1 as the anode (ground) and the targets 2 and 3 as the cathode, and generating the above-mentioned magnetic field by the permanent magnets 12 and 13. A film having a composition corresponding to the targets 2 and 3 is formed on the surface of the substrate 4.

At this time, since a magnetic field is generated perpendicularly to the sputtering surface by the above-described configuration, high-energy electrons are confined in the space between the opposing targets 2 and 3, and ionization of the sputtering gas in this space is promoted. As a result, the sputtering rate is increased and high-speed film formation is possible. In addition, since the substrate 4 is arranged on the side of the targets 2 and 3 without facing the target as in the conventional sputtering apparatus, there is almost no collision of ions or electrons having high energy on the surface of the substrate 4. In addition, the heat radiation from the targets 2 and 3 is small, and the temperature rise of the substrate 4 is suppressed, and a film can be formed on the surface of the substrate 4 at a low temperature.
JP 57-158380 A JP 59-053680 A JP 58-189731 A

Certainly, the above-described conventional counter target sputtering apparatus has excellent features such as sputtering at a low temperature, but the erosion region of the target is formed inclined with respect to the direction of the lines of magnetic force. In this case, the shape of the erosion region of the target material to be cut by Ar ⁺ ions becomes an elliptical shape, but its central axis is not parallel to the target side but is rotated. Therefore, in the conventional facing target sputtering apparatus, it is not parallel to the film formation surface of the substrate, and depending on the location of the substrate and the position in the substrate surface, the portion near the erosion is thick, the portion far from the erosion is thin, and the film thickness that adheres There is a problem that the manufacturing yield is deteriorated.

  Furthermore, there is a problem that the substrate temperature is high near the erosion and low at the distant place due to the substrate placement position and the position in the substrate surface, resulting in a difference in the substrate temperature.

  In view of the above-described conventional problems, the present invention can improve the manufacturing yield by making the erosion central axis the same distance from the substrate, improving the film thickness uniformity, and reducing the temperature variation of the substrate. It is an object of the present invention to provide an opposed target sputtering apparatus and method.

  In order to solve the above problem, an opposed target sputtering apparatus of the present invention is provided with a vacuum chamber capable of maintaining a vacuum, a substrate holder disposed in the vacuum chamber and on which a substrate is placed, and opposed to the substrate holder. A target holder for placing the target, a magnet arranged on the opposite side of the surface of the target holder on which the target is placed, a sputtering power source for applying a direct current power to the target holder, and a vacuum chamber Gas supply / exhaust means for introducing or exhausting gas, and the central axis in the longitudinal direction of the magnet is inclined with respect to the central axis in the longitudinal direction of the target holder.

  As a result, the central axis of the erosion is equidistant with respect to the substrate, the film thickness formed on the surface of the substrate can be made uniform, and the temperature variation of the substrate can be reduced, The production yield can be improved.

  At this time, it is preferable that a plurality of target holders are arranged to face each other, a plurality of substrates are placed on the side of the target holder, and a substrate holder capable of rotating is provided.

  A plurality of substrate holders may be provided around the plurality of target holders.

  Furthermore, the facing target sputtering method of the present invention introduces and evacuates a gas into the vacuum chamber, and applies a direct current power source to a target holder on which the target placed in the vacuum chamber is placed, whereby the vacuum chamber In the facing target sputtering method for generating plasma in the substrate and processing a substrate provided on the side of the target, the surface of the target is formed by a magnet disposed on the opposite side of the surface on which the target is placed in the target holder. And the substrate is processed in a state where the longitudinal center axis of the magnet is inclined with respect to the longitudinal center axis of the target holder.

  As a result, the central axis of the erosion is equidistant with respect to the substrate, the film thickness formed on the surface of the substrate can be made uniform, and the temperature variation of the substrate can be reduced, The production yield can be improved.

  As described above, according to the counter target sputtering apparatus of the present invention, it is possible to improve the film thickness uniformity in the substrate placement location and the substrate surface. Further, variations in the substrate deposition location and the sputtering film forming temperature within the substrate surface can be reduced. Furthermore, since it has a simple configuration in which a magnet or a target and a target holder and a cathode including the magnet are simply installed at an angle, the equipment is inexpensive.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a diagram for explaining rotation of an erosion region of a target for explaining the first embodiment of the present invention.

  In FIG. 1, the target 2, the permanent magnet 12, and the substrate 4 are views as seen from P in FIG. 6. Reference numeral 19 denotes an erosion region by sputtering, and reference numeral 21 denotes a central axis of the elliptical erosion region 19. Is. As described above, the erosion region 19 caused by sputtering has a phenomenon of rotating about the direction of the magnetic force line H in FIG.

  At this time, although not shown in FIG. 1, the erosion region 19 of the target 2 is also rotated in the same direction by the same angle. The amount of this rotation varies depending on the strength of the magnetic field, shape, distance between targets, power, and the like. When the erosion region 19 rotates, the film formation surface of the substrate 4 and the central axis 21 of the erosion region 19 are not parallel, so that the end of the erosion region 19 is not equidistant from the substrate 4. Accordingly, the film thickness on the substrate 4 varies due to the difference in distance from the erosion region 19. Furthermore, temperature variations in sputter film formation also occur.

  2 shows the positional relationship between the substrate 2 and the permanent magnet 12 and the substrate 4 in the counter target sputtering according to the first embodiment of the present invention.

  In FIG. 2, the components are the same as those in FIG.

  In FIG. 2, the permanent magnet 12 is arranged so that the central axis 21 of the erosion region 19 in FIG. 1 is rotated at an angle parallel to the film formation surface of the substrate 4. Although not shown in FIG. 2, the erosion region 19 is also provided in the same direction as the permanent magnet 12 with the direction of the magnetic force line H in FIG. 6 as the axis for the permanent magnet 13 installed behind the opposing target 3. The substrate 4 is rotated and arranged at an angle parallel to the film formation surface of the substrate 4.

When sputtering is performed with the opposed target sputtering apparatus configured as described above, an elliptical erosion region 19 cut by Ar ⁺ ions is generated on the surface of the target 2. At this time, since the permanent magnet 12 is rotated, the central axis 21 of the erosion region 19 is parallel to the film formation surface of the substrate 4, that is, the end of the erosion region 19 is approximately equal to the substrate 4. Distance. Although not shown, since the permanent magnet 13 is also rotated and arranged in the elliptical erosion region 20 on the surface of the opposing target 3, the end of the erosion region 20 is approximately equidistant from the substrate 4. Become.

  Therefore, variations in film thickness due to the location of the substrate 4 and in-plane position can be reduced, and film thickness uniformity can be improved. Further, the temperature rise due to the plasma of the sputtering is also reduced because the erosion regions 19 and 20, that is, the edges of the plasma are approximately equidistant with respect to the substrate 4, thereby reducing temperature variations due to the location of the substrate 4 and the position in the plane. The film quality can be stabilized. Furthermore, the above result can be obtained with a cheap sputter cathode in which the permanent magnets 12 and 13 are rotationally arranged.

  In the present embodiment, it is desirable that the permanent magnets 12 and 13 are installed in a mechanism that can adjust the rotation angle.

(Embodiment 2)
FIG. 3 is a diagram showing a positional relationship between the substrate 2 and the permanent magnet 12 and the substrate 4 in the counter target sputtering according to the second embodiment of the present invention.

  In FIG. 3, since the components are the same as those in FIG.

  In FIG. 3, the cathode including the target 2 and the permanent magnet 12 is arranged to rotate at an angle at which the central axis 21 of the erosion region 19 in FIG. 1 is parallel to the film formation surface of the substrate 4. Although not shown, the cathode including the target 3 and the permanent magnet 13 facing each other also has the erosion region 20 of the substrate 4 in the same direction as the target 3 and the permanent magnet 12 with the direction of the magnetic force line H in FIG. It is rotated and arranged at an angle parallel to the film formation surface.

When sputtering is performed with the opposed target sputtering apparatus configured as described above, an elliptical erosion region 19 cut by Ar ⁺ ions is generated on the surface of the target 2. At this time, since the cathode including the target 3 and the permanent magnet 12 is rotated, the central axis 21 of the erosion region 19 is parallel to the film formation surface of the substrate 4, that is, the end of the erosion region 19 is the substrate. 4 is approximately equidistant. Although not shown in the figure, the elliptical erosion region 20 on the surface of the opposing target 3 is also arranged so that the target 3 and the permanent magnet 13 are rotated, so that the end of the erosion region 20 is approximately at the substrate 4. Equidistant.

  Therefore, variations in film thickness due to the location of the substrate 4 and in-plane position can be reduced, and film thickness uniformity can be improved. Further, the temperature rise due to the plasma of the sputtering is also reduced because the erosion regions 19 and 20, that is, the edges of the plasma are approximately equidistant with respect to the substrate 4, thereby reducing temperature variations due to the location of the substrate 4 and the position in the plane. The film quality can be stabilized. Furthermore, the above result can be obtained with a sputter cathode at a low price by simply rotating the cathode including the targets 2 and 3 and the permanent magnets 12 and 13.

  In this embodiment, it is desirable that the cathode 2 including the targets 2 and 3 and the permanent magnets 12 and 13 be a mechanism that can adjust the rotation angle.

(Embodiment 3)
FIG. 4 is a schematic cross-sectional view of the counter target sputtering apparatus according to the third embodiment of the present invention.

  In FIG. 4, the same components as those in FIG.

  In FIG. 4, reference numeral 101 denotes a carousel that is a substrate holder on which a plurality of substrates 4 can be placed. The carousel is disposed on the side of the space of the targets 2 and 3 so as to face the space and is rotatable.

  Further, the cathode including the target 2, the permanent magnet 12 and the target holder 6 has the configuration shown in FIG. 3 described in the second embodiment, and the central axis 21 of the erosion region 19 is parallel to the film formation surface of the substrate 4. It is arranged to be rotated at an angle, and is further parallel to the rotation axis of the carousel 101.

  Further, the cathode including the target 3, the permanent magnet 13 and the target holder 7 is also eroded in the same direction as the cathode including the target 2, the permanent magnet 12 and the target holder 6 with the direction of the magnetic force line H in FIG. 20 is rotated and arranged at an angle parallel to the film formation surface of the substrate 4.

  The operation of the counter target sputtering apparatus configured as described above will be described.

  First, after evacuating the inside of the vacuum chamber 1 through the exhaust port 16 by an exhaust system (not shown), a sputtering gas such as argon is introduced from the gas introduction system (not shown) through the introduction port 17, and a sputter composed of a DC power source as shown in the drawing. Sputtering is performed by supplying the sputtering power by the power source 18 with the shields 14 and 15 and the vacuum chamber 1 as the anode (ground) and the targets 2 and 3 as the cathode, and generating the above-mentioned magnetic field by the permanent magnets 12 and 13. A film having a composition corresponding to the targets 2 and 3 is formed on the substrate 4 placed on the carousel 101. At this time, since the carousel 101 in which a plurality of substrates 4 are installed rotates at about 50 to 500 rpm, film thickness variation in the rotation direction of the carousel 101 due to the location of the substrate 4 and the position in the surface of the substrate 4 is reduced. Uniformity will be improved.

  Furthermore, since the targets 2 and 3, the permanent magnets 12 and 13, and the target holders 6 and 7 have the configuration of FIG. 3 described in the second embodiment, the end of the erosion region 19 is approximately equidistant from the substrate 4. The ends of the erosion region 20 are also equidistant from the substrate 4.

  Therefore, the film thickness variation in the direction of the rotation axis of the carousel 101 due to the location of the substrate 4 and the position in the plane can be reduced, and the film thickness uniformity can be greatly improved together with the effect of rotation of the carousel 101. Further, in the conventional sputtering, the film thickness distribution in the direction of the rotation axis of the carousel 101 uses a projection effect. For example, where the film thickness increases, a plate or the like is provided between the substrate 4 and the targets 2 and 3. In many cases, the uniformity is improved by blocking a part of the sputtered particles to improve the uniformity. However, according to the present embodiment, the use of the projection effect can be suppressed as much as possible. Increase material efficiency and reduce product costs.

  Further, with respect to the temperature rise due to the plasma of sputtering, since the erosion regions 19 and 20, that is, the ends of the plasma are approximately equidistant from the substrate 4, temperature variations due to the location of the substrate 4 and the position in the plane can be reduced. The film quality can be stabilized. Furthermore, the above results can be obtained with a sputter cathode that is inexpensive enough to rotate the cathode including the targets 2 and 3 and the permanent magnets 12 and 13.

  In the present embodiment, the cathode is described in the configuration of the second embodiment, but the configuration of the first embodiment may be used.

(Embodiment 4)
FIG. 5 is a schematic cross-sectional view of the counter target sputtering apparatus according to the fourth embodiment of the present invention. 5, the same components as those in FIGS. 4 and 6 are denoted by the same reference numerals, and the description thereof is omitted.

  In FIG. 5, reference numerals 16a and 16b are exhaust ports for exhausting the vacuum chamber 1 by an exhaust system (not shown), and reference numerals 17a and 17b are introduction ports for introducing a sputtering gas such as argon from a gas introduction system (not shown). .

  Reference numeral 102 denotes a carousel that is a substrate holder on which a plurality of substrates 4a can be placed. The carousel is disposed on the side of the space of the targets 2 and 3 so as to face the space and is rotatable. Reference numeral 103 denotes a carousel which is a substrate holder on which a plurality of substrates 4b can be placed, and is arranged at a position facing the carousel 102.

  Further, the cathode including the target 2, the permanent magnet 12 and the target holder 6 has the configuration shown in FIG. 3 described in the second embodiment, and the central axis 21 of the erosion region 19 is the substrate 4a installed on the carousels 102 and 103. , 4b are rotated at an angle parallel to the film formation surface, and are further parallel to the rotation axes of the carousels 102 and 103.

  Further, the cathode including the target 3, the permanent magnet 13 and the target holder 7 is also eroded in the same direction as the cathode including the target 2, the permanent magnet 12 and the target holder 6 with the direction of the magnetic force line H in FIG. 20 is arranged to be rotated at an angle parallel to the film formation surfaces of the substrates 4a and 4b, and is parallel to the rotation axes of the carousels 102 and 103.

  The operation of the counter target sputtering apparatus configured as described above will be described.

  First, after exhausting the inside of the vacuum chamber 1 through the exhaust ports 16a and 16b through an exhaust system (not shown), a sputtering gas such as argon is introduced through the introduction ports 17a and 17b from the gas introduction system (not shown). As described above, sputtering power is supplied by a sputtering power source 18 composed of a DC power source with the shields 14 and 15 and the vacuum chamber 1 as an anode (ground) and the targets 2 and 3 as a cathode, and the above-mentioned magnetic field is supplied by permanent magnets 12 and 13. Sputtering is performed to generate a film having a composition corresponding to the targets 2 and 3 on the substrates 4a and 4b installed on the carousels 102 and 103 rotating at about 50 to 500 rpm.

  At this time, sputtered particles scattered from the targets 2 and 3 are scattered all around the sides of the spaces of the targets 2 and 3. However, in the conventional counter target sputtering apparatus, the substrate 4 a and the like are placed in the space of the targets 2 and 3. Since it arrange | positions only to one direction of a side, the utilization efficiency of target material becomes low. However, according to the embodiment of the present invention, the two carousels 102 and 103 are arranged on the sides of the space of the targets 2 and 3 and the substrates 4a and 4b are installed. It is possible to improve the film forming processing capability by a factor of 2 or more.

  Further, in the conventional counter target sputtering apparatus, as shown in FIG. 1, the erosion regions 19 and 20 rotate about the direction of the magnetic force line H, so that the film thickness variation on the substrate 4 rotates in both the carousels 102 and 103. Increases in the axial direction. Furthermore, the thickness distribution shapes of the substrate 4 in the carousels 102 and 103 are different in the axial direction and are almost opposite.

  Therefore, in the embodiment of the present invention, the cathode including the targets 2 and 3, the permanent magnets 12 and 13 and the target holders 6 and 7 has the configuration shown in FIG. Are approximately equidistant from the substrates 4a and 4b installed in the carousels 102 and 103, and the ends of the erosion region 20 are also approximately equidistant from the substrates 4a and 4b installed in the carousels 102 and 103.

  Therefore, in both the carousels 102 and 103, variations in film thickness in the direction of the rotation axis of the carousels 102 and 103 due to the location and in-plane positions of the substrates 4a and 4b are reduced, and the substrates installed in the carousels 102 and 103 are further reduced. The film thickness, film thickness distribution, and film quality of 4a and 4b can be made substantially the same, so that the manufacturing yield can be improved and the cost can be reduced. Further, as in the third embodiment, it is possible to suppress the use of the projection effect as much as possible.

  Regarding the temperature rise due to the plasma of sputtering, since the cathodes including the targets 2 and 3, the permanent magnets 12 and 13 and the target holders 6 and 7 have the configuration of FIG. 3 described in the second embodiment, The ends of the plasma are approximately equidistant from the substrates 4a and 4b installed in the carousels 102 and 103, and the ends of the erosion region 20 are also approximately equidistant from the substrates 4a and 4b installed in the carousels 102 and 103, In both carousels 102 and 103, temperature variations due to the location of the substrates 4a and 4b and in-plane positions can be reduced, and the film quality can be stabilized.

  Note that the cathode in the present embodiment is the same as that described in the configuration of the second embodiment, but may be configured in the first embodiment.

  In this embodiment, two carousels are arranged on the sides of the target space. However, two carousels may be arranged on the other sides, that is, a plurality of carousels may be arranged.

  As long as it is an opposed target sputtering apparatus, the present invention can be used regardless of the shape and material of the sample, or whether it is moving or not.

Diagram explaining rotation of target erosion area The figure which rotates the erosion area | region in Embodiment 1 of this invention The figure which rotates the erosion area | region in Embodiment 2 of this invention Schematic cross-sectional view of the counter target sputtering apparatus in Embodiment 3 of the present invention Schematic cross-sectional view of the counter target sputtering apparatus in Embodiment 4 of the present invention Schematic sectional view of a conventional counter target sputtering system

Explanation of symbols

1 Vacuum chamber 2, 3 Target 4, 4a, 4b Substrate 5 Substrate holder 6, 7 Target holder 8a, 9a Supply pipe (cooling water)
8b, 9b Discharge pipe (cooling water)
10, 11 Insulating member 12, 13 Magnet (magnetic field generating means)
14, 15 Shield 16, 16a, 16b Exhaust port (exhaust system)
17, 17a, 17b Inlet (gas introduction system)
18 Sputtering power source 19, 20 Erosion area 21 Center axis of erosion area 101, 102, 103 Carousel

Claims (4)

A vacuum chamber capable of maintaining a vacuum, a substrate holder disposed in the vacuum chamber and placing a substrate thereon, a target holder placing a target provided facing the substrate holder, and a target among the target holders A magnet disposed on the opposite side of the surface on which the magnet is placed, a sputtering power source for applying a DC power source to the target holder, and gas supply / exhaust means for introducing or exhausting gas into the vacuum chamber, An opposed target sputtering apparatus, wherein a longitudinal center axis is inclined with respect to a longitudinal center axis of the target holder. The counter target sputtering according to claim 1, wherein a plurality of target holders are arranged to face each other, a plurality of substrates are placed on the sides of the target holder, and a substrate holder capable of rotating is provided. apparatus. The counter target sputtering apparatus according to claim 2, wherein a plurality of substrate holders are provided around the plurality of target holders. Gas is introduced into the vacuum chamber and exhausted, and a DC power source is applied to a target holder on which the target placed in the vacuum chamber is placed, thereby generating plasma in the vacuum chamber, and the side of the target In the facing target sputtering method for processing a substrate provided on the side, a magnetic field is generated on the surface of the target by a magnet disposed on the opposite side of the surface on which the target is placed in the target holder, and the magnet An opposed target sputtering method, wherein the substrate is processed in a state in which a central axis in a longitudinal direction is inclined with respect to a central axis in a longitudinal direction of the target holder.

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