JP2001077052A - Sputtering system and film-forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to achieve a full bottom coverage in a sputtering system. SOLUTION: In a sputtering system of a structure wherein a magnetron unit 31 is arranged on the opposite side to a target 16, the unit 31 has first magnet parts 43 and 49 and second magnet parts 43 and 47 arranged on the outsides of the magnet parts 43 and 49. The total quality of the magnetisms of the magnet parts 43 and 49 is smaller than that of the magnetisms of the magnet parts 43 and 47. One part of the magnetic fluxes of the magnet parts 43 and 47 passes through the magnet parts 43 and 49 to shut the one part in the magnet parts 43 and 47. The remaining part of the magnetic fluxes of the magnets 47 and 47 forms such a magnetic flux loop as to comprise the magnet parts 43 and 49 in its inside to shut the remaining part in the magnets 43 and 47. Hereby, a confinement of electrons is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a sputtering apparatus and a film forming method.

[0002]

2. Description of the Related Art A sputtering apparatus includes a sputter target, a wafer support provided to face an erosion surface of the sputter target, and a magnetron unit provided to face the back of the sputter target.
Is provided. In such a sputtering apparatus, particles to be sputtered are generated from the sputter target by introducing a process gas into a vacuum chamber and generating plasma near the sputter target. The particles to be sputtered reach the wafer, whereby the film formation proceeds.

[0003]

With the miniaturization of design rules in semiconductor devices, there is an increasing demand for achieving sufficient coverage at the bottom of connection holes such as contact holes and via holes having a high aspect ratio. In order to meet such a demand, the inventor is studying a method for improving bottom coverage in a sputtering apparatus.

Accordingly, it is an object of the present invention to provide a sputtering apparatus and a film forming method capable of improving bottom coverage.

[0005]

Means for Solving the Problems In order to solve such technical problems, the inventor has further studied. As a result, for example, when improving bottom coverage at the bottom of a connection hole having a high aspect ratio, it has been found that it is effective to reduce the pressure of a process gas introduced into a sputtering apparatus.

However, according to experiments, it has been found that simply lowering the pressure of the process gas cannot maintain the plasma for generating sputtering. Based on the results of this experiment, the inventors further studied.
The reason that the plasma is not maintained when the process gas is at a low pressure is that the number of electron sources required to maintain the plasma is reduced as the pressure is reduced, and the electrons in the plasma escape to one of the conductive parts. I thought it would go away.

In order not to lower the electron density, (a) a method of adding a new electron source, and (b) a method of confining generated electrons so as not to escape. In order to add more electrons, it is necessary to introduce some kind of gas, so it is important to prevent generated electrons from escaping. Therefore, in order to find a way for electrons to escape, the structure of the sputtering apparatus was sufficiently examined. A shield is provided in the vacuum chamber. The inventor has noted that this shield is grounded. From the relationship between the plasma potential and the shield potential, it was considered that some of the electrons in the plasma were flowing through this shield. That is, if the number of electrons flowing through the shield is reduced, the electron density can be increased.

The inventor feels that in order to reduce the electron flow to the shield, it is necessary to further understand the magnitude and direction of the magnetic and electric fields in the vacuum chamber and the movement of the electrons in the electromagnetic field. Was.

Generally, electrons move in a direction corresponding to the direction of an electric field while drawing a curve in a magnetic field. The magnetic field generated by the magnetron unit also extends outside the vacuum chamber. For this reason, some of the electrons rotating in such a magnetic field may reach the shield. In other words, it has been found that such a magnetic field contributes to the generation of plasma, but does not act to sufficiently confine generated electrons.

[0010] Accordingly, it has been concluded that a magnetic field for confining electrons in the plasma may be generated by the magnetron unit. Thus, the inventor has made the following invention after such various trial and error.

[0011] The sputtering apparatus according to the present invention comprises:
(1) a vacuum chamber, (2) decompression means for depressurizing the chamber, (3) gas supply means for supplying a process gas into the vacuum chamber, and (4) supporting the substrate in the vacuum chamber And (5) a sputter target, and (6) a magnetron unit.

In such a sputtering apparatus,
The erosion surface of the sputter target faces the substrate support. The magnetron unit is provided on the side opposite to the substrate support with respect to the sputter target.

This magnetron unit has a first magnet section and a second magnet section provided to generate a magnetic field in a vacuum chamber. The second magnet section is disposed outside the first magnet section. The total magnetic amount of the first magnet unit is smaller than the total magnetic amount of the second magnet unit.

For this reason, the magnetic field generated by these magnet portions acts to reduce escape of electrons in the plasma from the plasma. Therefore, the performance of confining electrons to the region near the target is improved.

The first magnet section and the second magnet section
May take various forms as described below.

In the sputtering apparatus according to the present invention,
The magnetron unit can have a plurality of first magnets and a plurality of second magnets. The plurality of first magnets are arranged with the first magnetic pole facing the target. The plurality of second magnets are arranged with the second magnetic pole facing the target. The first
Are different from the second magnetic pole.

If each magnet section has a plurality of magnets, the shape of the magnetic field generated by each magnet section can be changed according to the arrangement position of the magnet.

It is preferable that the second magnet section is composed of a magnet arranged on the outermost periphery. This is because electrons in the plasma can be confined inside the second magnet portion.

In the sputtering apparatus according to the present invention,
The magnetron unit may include a magnetic member provided so that the first and second magnet units form a magnetic circuit.

Further, in the sputtering apparatus according to the present invention, the magnetron unit may have a plurality of first magnetic members. Each first magnetic member supports one of the plurality of first magnets and one of the plurality of second magnets.
According to these first magnetic members, a magnetic circuit that enables the plurality of first magnets to be individually magnetically coupled to the plurality of second magnets is configured. The magnetron unit can also have this second magnetic member. The second magnetic member supports a plurality of first magnets and a plurality of second magnets. According to the second magnetic member, a magnetic circuit capable of magnetically coupling the plurality of first magnets to the plurality of second magnets as a whole is configured.

In the sputtering apparatus according to the present invention,
The magnetron unit can have a third magnetic member and a fourth magnetic member. Each of the third magnetic members is provided over each of the first magnet ends, and magnetically couples the first magnetic pole of each magnet. Each of the fourth magnetic members is provided over each of the second magnet ends, and magnetically couples the second magnetic pole of each magnet.

Since the third and fourth magnetic members are provided so as to magnetically couple the adjacent magnets, the magnetic flux can be guided to each region between the magnets where no magnet exists. For this reason, the magnetic flux from each magnet is averaged by these magnetic members, and given to the sputter target. Also, individual differences in the amount of magnetism between adjacent magnets are averaged.

In the sputtering apparatus according to the present invention,
The first and second magnet units can take the following forms. The first magnet unit may include a plurality of first magnets having one end indicating a first magnetic pole and the other end indicating a second magnetic pole, with the one end facing the target. The second magnet section has one end indicating a second magnetic pole and the other end indicating a first magnetic pole, and has a plurality of annularly disposed outside the plurality of first magnets with the one end facing the target. A second magnet can be included.

[0024] The magnetron unit can include a first magnetic member, a third magnetic member, and a fourth magnetic member. The third magnetic member is provided annularly so as to connect one ends of the plurality of first magnets. The fourth magnetic member is provided annularly so as to connect one ends of the plurality of second magnets. Further, the second magnet part
It has a total magnetic amount that is 1.5 times or more the total magnetic amount of the first magnet unit.

In such an embodiment, the plurality of first magnets and the plurality of second magnets are further interposed via the second magnetic member.
Can be magnetically coupled to form a magnetic circuit. In the above embodiment, one of the first magnets and one of the second magnets can be magnetically coupled individually via the first magnetic member to form a magnetic circuit.

In the sputtering apparatus according to the present invention,
A unit magnet having a predetermined magnetic quantity can be applied to each of the plurality of first and second magnets. When the unit magnet is employed, the total magnetic amount of each of the first magnet portion and the second magnet portion can be easily grasped, and the setting of the total magnetic amount ratio becomes easy.

In the sputtering apparatus according to the present invention,
The sputtering target may include at least one of Ti, Al, and Cu.

The film forming method according to the present invention comprises: (1) a first magnet portion provided so as to direct a first magnetic pole to a target; and a first magnet portion disposed annularly outside the first magnet portion and provided on a target. A second magnet unit provided so as to direct two magnetic poles, and a sputtering apparatus having a magnetron unit in which the total magnetic amount of the first magnet unit is smaller than the total magnetic amount of the second magnet unit is prepared. Steps, (2) a step of arranging the substrate so as to face the target, (3) a step of introducing a process gas into a vacuum chamber, and (4) a step of depositing sputtered particles on the substrate to form a film , Is provided.

Further, in the film forming method according to the present invention, (5) a step of disposing a substrate so as to face a target;
Introducing a process gas into the vacuum chamber; (7)
A first magnet portion provided with the first magnetic pole facing the target and a second magnetic pole facing the magnetic member; and a second magnetic pole arranged annularly outside the first magnet portion to face the target. A second magnet portion provided with the second magnetic pole facing the magnetic member, wherein plasma is generated using a magnetron unit in which the total amount of magnetism of the first magnet portion is smaller than the total amount of magnetism of the second magnet portion. And (8) a step of depositing sputtered particles on a substrate to form a film.

If plasma is generated using the magnetron unit as described above, electrons in the plasma can be efficiently confined. Therefore, the electron density can be increased in the plasma. The higher electron density allows the plasma to be maintained at lower pressures, thereby improving bottom coverage.

Since the plasma is maintained even when the pressure of the process gas is lowered, the pressure of the process gas can be reduced. Therefore, the probability of collision between the particles to be sputtered and the atoms of the process gas is reduced. As the collision probability decreases, the number of sputtered particles directed from the target to the substrate increases.

[0032]

Embodiments of the present invention will be described with reference to the drawings. Where possible, the same parts are denoted by the same reference numerals, and redundant description will be omitted.

Next, a sputtering apparatus according to the present invention will be described. FIG. 1 is a schematic configuration diagram of a magnetron sputtering apparatus according to an embodiment of the present invention.

The sputtering apparatus 10 includes a housing 14 inside which a vacuum chamber 12 is formed, and a housing 1
Target 1 arranged so as to close the upper opening of 4
6 is provided. Housing 14 and target 16
Are made of a conductive material, an insulating member 13a is interposed between the housing 14 and the target 16. In the embodiment shown in FIG.
Reference numeral 4 has a circular bottom surface and a tubular portion extending a predetermined distance from the periphery of the circular bottom surface. For example, the tubular portion has a cylindrical shell shape. The shape of the target 16 is a disk shape. One circular surface 16a of the target 16 (hereinafter, referred to as a lower surface) is an erosion surface that receives erosion by sputtering.

In the vacuum chamber 12, substrate supporting means is provided.
A pedestal 18 is provided as a substrate support (also referred to as a substrate support). The pedestal 18 supports the substrate 15 in the vacuum chamber 12. Therefore, pedestal 1
8 denotes a substrate 15 to be processed, for example, a semiconductor wafer W
Or a glass substrate, one surface of which (hereinafter referred to as the upper surface)
Hold on 18a. Upper surface 1 of pedestal 18
8a is a lower surface (erosion surface) 16a of the target 16.
Are provided so as to face each other. The surface 15 a of the substrate 15 (wafer W) to be deposited, which is held at a predetermined position on the pedestal 18, is disposed substantially parallel to the lower surface 16 a of the target 16.

The substrate 15 is arranged so that its center is aligned with the center of the target 16, that is, coaxially. This center preferably coincides with the center of rotation (rotation axis 38) of the magnetron unit in order to improve the in-plane uniformity of the formed film. In this embodiment, the distance between the pedestal 18 and the target 16 is preferably about 0.95 times the diameter of the substrate on which the sputtered particles are deposited.

The sputtering apparatus 10 has a shield 26 for preventing the sputtered particles from reaching the inner wall surface in order to protect the inner wall surface of the vacuum chamber 12 from the sputtered particles. One edge of the shield 26 is insulated from the housing 14 via the insulating member 13a. One side of the shield 26 is fixed at the edge of the upper opening of the housing. Another side of the shield 26 leads to the side of the pedestal 18. The other edge is insulated along the side surface of the pedestal 18 via an insulating member 13b. For this reason, the shield 26 is electrically insulated from the pedestal 18.

The pedestal 18 is connected via a capacitor 19 to a reference potential, for example, a ground potential. The shield 26 is connected to a predetermined reference potential. Because of the provision of the capacitor 19, the pedestal 18 can also be used in a self-biased state by electrons provided by the plasma. Further, a high frequency can be applied through the capacitor 19 to use the device in an RF bias state. In this case, bias means such as RF bias applying means is provided between the capacitor 19 and the reference potential source. In any case, the pedestal 18
The bias is preferably negative with respect to the plasma potential, and is preferably negative with respect to the target 16.

An exhaust port 20 is formed in the housing 14. In the case of the present embodiment, the exhaust port 20
Is connected to a vacuum pump 21 such as a cryopump. By operating this vacuum pump 21,
The pressure inside the vacuum chamber 12 can be reduced. The exhaust port 20 and the vacuum pump 21 constitute a pressure reducing unit. A process gas such as an argon gas or a nitrogen gas is supplied from the process gas supply source 25 into the vacuum chamber 12 through the supply port 22. The supply port 22 can be opened and closed by a valve 23. By opening and closing the valve 23, it is possible to control the presence / absence, supply amount, and supply timing of the process gas. The supply port 22 and the process gas supply source 25 constitute a process gas supply unit.

In order to apply a voltage between the target 16 and the shield 26, a power supply 24 is connected as one of the plasma generating means. When a process gas, for example, an argon gas is introduced into the vacuum chamber 12 and a voltage is applied between the target 16 and the shield 18, a glow discharge occurs and a plasma state is generated. When the argon ions generated by this discharge collide with the lower surface 16a of the target 16, atoms constituting the target 16 are repelled, and sputtered particles are generated. When the target atoms reach and accumulate on the wafer W, a film is formed on the wafer W.

A magnetron unit 30 for increasing the plasma density in a space near the erosion surface of the target 16 is arranged on the surface facing the lower surface 16a of the target 16, that is, on the upper surface 16b of the target 16.

The sputtering apparatus 10 can include a controller 29. Since the controller 29 includes a microcomputer, a timer, and the like, it is possible to perform control of turning on and off the current, change of the current value, and the like, including temporal control. The controller 29 includes a valve 23, an acceleration power source 2
4 and the driving motor 36 via a control line 29a. The controller 29 can control these devices while correlating them. Therefore, the supply of the process gas, the generation of the plasma of the process gas, and the like can be controlled in synchronization with a predetermined timing.

FIG. 2 is a plan view showing the positions of magnets on each magnetron unit. FIG. 2 is a cross-sectional view of FIG.
1 shows a cross section taken along the line I.

Referring to FIGS. 1 and 2, the magnetron unit 30 includes a circular base plate 32 and a plurality of subunits 34 fixed in a predetermined arrangement on a mounting surface 32a of the base plate 32. The base plate 32 is attached to the substrate support 18 with respect to the target 16.
The rotation shaft 38 of the drive motor 36 is connected to the center of the upper surface. Therefore, when the drive motor 36 is operated to rotate the base plate 32, each subunit (also called a magnet assembly)
The swivel 34 rotates along the upper surface of the target 16 to prevent the magnetic field generated by the subunit 34 from stopping in one place.

Referring to FIG. 2, a plurality of magnet assemblies 34 are annularly arranged. Each magnet assembly 34 has one magnetic pole (N pole in the example of FIG. 2) facing the outside of the array, and the other magnetic pole (S pole in the example of FIG. 2) facing the inside of the array. The end of the same magnetic pole of each magnet assembly is a magnetic member 48 such as a pole piece,
Magnetically coupled via 50. Magnetic member 48,
Reference numeral 50 (in FIG. 2, drawn by a broken line because it overlaps with the magnet) is a band-shaped member that is in contact with the end having the same magnetic pole of each magnet assembly, and is provided in an annular shape. An outer annular region and an inner region are formed on the erosion surface corresponding to the magnetic field from the band-shaped member. In the outer annular region, for example, magnetic lines of force generated by the outermost magnet group (N pole of the magnet of the magnet assembly 34) extend into the vacuum chamber. These lines of magnetic force extend inward, and some of them reach the inner group of magnets (the south pole of the magnet of the magnet assembly) through the inner annular magnetic field region.

Since the magnetic members 48 and 50 are provided between the magnet assembly 34 and the sputter target 16, the adjacent magnets can be magnetically coupled. For this reason, magnetic flux is also guided to a region between the magnets where no magnet exists. With these magnetic members,
The magnetic flux from each magnet is averaged and applied to the sputter target. Further, the magnetic members 48 and 50 form a magnetic field having a predetermined strength even when the magnets are discretely arranged. Therefore, the confinement of the plasma by the magnetic field is improved. Further, the non-uniformity of the magnetic quantity between adjacent magnets and the individual differences of the magnets themselves are also averaged. This factor also has an advantageous effect on electron confinement.

Further, the magnetron unit 30 can have one or more first magnet assemblies 34a and one or more second magnet assemblies 34b. The first magnet assembly 34a is provided so as to regulate a magnetic field to be formed in the vicinity of a rotation shaft 38 serving as a rotation center.

The arrangement of the magnet assembly for this purpose will be described later with reference to FIGS. 4 to 7, but will be described schematically here. The mounting surface 32a of the base plate 32 is divided into two regions by a surface including the rotation shaft 38, one of which is referred to as a first region and the other is referred to as a second region. In this arrangement, (i) when the first magnet assembly 34a is arranged in the first region, (ii) the first magnet assembly 34a is mounted on the surface including the rotating shaft 38 and the magnetron unit 30. (Iii) when the outer magnet of the first magnet assembly 34a is arranged in the first and second regions, and when the second magnet assembly 34b is arranged on the line intersecting the surface and over the first region. The case where it is arranged in the first area is considered. In each case, each of the second magnet assemblies 34b is
Are provided so as to form an annular arrangement together with the magnet assembly 34a. According to experiments performed by the inventor, particularly preferable results were obtained in the configurations shown in FIGS. 4, 6 and 7.

The magnetron unit 30 has a first
The outer magnet portion provided with its magnetic pole (N pole in the example of FIG. 2) facing the erosion surface, and the inner magnet portion provided with the second magnetic pole (S pole in the example of FIG. 2) facing the erosion surface. Have. The inner magnet part can include all magnets provided inside the outer peripheral magnet part. The outer peripheral magnet portion may be composed of, for example, an outermost magnet group, and the inner magnet portion may be composed of, for example, a magnet group inside the outermost magnet. The strength of each magnet unit or each magnet can be defined so that the total magnetic amount of the outer magnet unit is larger than the total magnetic amount of the inner magnet unit.

The inner magnet portion having the smaller total magnetic amount was disposed inside the outer magnet portion having the larger total magnetic amount. Therefore, a part of the magnetic flux of the outer peripheral magnet portion reaches the inner magnet portion, passes through the inner magnet portion, and closes at the outer peripheral magnet portion. Further, the remaining portion of the magnetic flux of the outer peripheral magnet portion forms a magnetic flux loop and closes at the outer peripheral magnet portion. Thus, magnetic flux extending outside the vacuum chamber is reduced near the erosion surface where the plasma is generated. Therefore, the confinement of electrons is improved.

FIG. 3 is a sectional view exemplarily showing a magnet assembly applicable to the sputtering apparatus 10. Each magnet assembly 34 includes a magnetic member 40 and bar magnets 42 and 44 as clearly shown in FIG. The magnetic member 40 is a flat yoke member made of a magnetic material. Each of the bar magnets 42 and 44 has an S pole at one end and an N pole at the other end. The bar magnet 42 is arranged with one end indicating the N pole facing the target 16, and the bar magnet 44 is arranged with one end indicating the S pole facing the target. The bar magnet 42 is fixed to each end of the magnetic member 40 with the other end indicating the S pole contacting the magnetic member 40, and the bar magnet 44 has the other end indicating the N pole contacting the magnetic member 40. . The two bar magnets 42 and 44 extend in the same direction, and the overall shape of the magnet assembly 34 is substantially U-shaped. The free end of one bar magnet 42 is N pole, and the free end of the other bar magnet 44 is S
It is a pole. Further, since the magnets 42 and 44 and the magnetic member 40 constitute a magnetic circuit, they constitute a magnet means functioning as an integral magnetic body in which different magnetic poles are directed in the same direction. This provides a controlled magnetic field in the vacuum chamber 12 that is suitable for confining electrons.

In the magnet assembly 34, a magnetic member 48 is provided at a free end N pole of each magnet 42 included in the outer peripheral magnet portion, and a magnetic member 48 is provided at a free end S pole of each magnet 44 included in the inner magnet portion. 50 are provided. These magnetic members 48 are mounted so as to mutually couple the magnets 42 in each magnetron unit as described above, and the magnetic members 50 are mounted so as to mutually couple the magnets 44.

Although the embodiment of FIGS. 2 and 3 shows a case in which each magnet unit has a plurality of magnets, a single unit may be used instead of each of the outer magnet unit and the inner magnet unit or one of them. One magnet may be provided. Also in this case, the magnetic amount of the outer peripheral magnet portion (magnet 42) is
(Magnet 44) is larger than the magnetic amount.

Although the magnet assembly 34 has been described with reference to FIG. 3, the form of the assembly 34 is not limited to this, and the magnet assembly 34 can include more magnets and magnetic members. . The amount of magnetism of the magnet used in each magnet assembly 34 is determined according to the magnetic field to be applied to the position where the magnet assembly 34 is arranged. For this reason, the strength of each magnet may be different.

In the magnet assembly 34 shown in FIG. 3, the free ends of the magnets 42 and 44 are
a are arranged so as to face each other on the surface 16b opposed to a. Such a magnet 34 is attached to a suitable fixing means such as a screw 46 or each magnet 4 with the back surface of the yoke member 40 being in contact with the base plate 32.
It is fixed to the base plate 32 by the magnetic force of 2, 44. With this configuration, the fixed position of the magnet assembly 34 can be freely changed, so that the shape of the magnetic field can be adjusted according to the position of the magnet assembly 34.

FIGS. 4, 6 and 7 are views showing a magnet assembly arrangement suitable for the sputtering apparatus 10. FIG. The line II-II in FIG. 4 corresponds to the cross section in FIG. In each of the drawings, an outer magnet portion 52 and an inner magnet portion 54 are used to indicate the location of a plurality of magnet assemblies. FIGS. 4, 6, and 7 show regions where the magnetic member 48 related to the outer magnet portion 52 and the magnetic member 50 related to the inner magnet portion 54 are respectively projected on the erosion surface. Since the magnetron unit 30 is rotating, the area indicates the relative positional relationship between the magnets 52 and 54 and the target 16 at a certain time.

Referring to FIG. 4, FIG. 6 and FIG. 7, the inner magnet portion 54 is located in any region of the magnetron unit 30 separated by a plane including the rotating shaft 38 (in the embodiment of FIGS. (The region above the region separated by the alternate long and short dash line 56). The outer magnet part 52 is provided so as to surround the inner magnet part 54.

The outer peripheral magnet portion 52 is provided so as to pass through or near the rotating shaft 38 in order to provide a magnetic field near the rotating shaft 38 serving as the center of rotation. For this reason, in the examples shown in FIGS. 4 and 7, the position of the outer peripheral magnet portion 52 and the position of the rotating shaft 38 overlap.
In the embodiment shown in FIG. 6, both the outer magnet section 52 and the inner magnet section 54 are provided in one of the regions separated by the dashed line 56. Also at this time, the outer peripheral magnet section 52 is arranged so as to apply a desired magnetic field to a position on the erosion surface corresponding to the rotating shaft 38. In FIG. 5, the outer magnet part 52 is positioned so as to include the rotating shaft 38 inside. Among these forms, the arrangement of the magnets in the embodiment of FIGS. 4 and 7 has the most preferable result. Also,
The embodiment of FIG. 6 produces better results than the magnet arrangement shown in FIG.

In the outer magnet portion 52 and the inner magnet portion 54 shown in FIGS. 4 and 6, the width of the outer shape in the direction along the axis 56 is longer than the length of the outer shape in the direction perpendicular to the axis 56. . The outer magnet part 52 and the inner magnet part 54 shown in FIG.
The width of the outer shape in the direction along 6 is shorter than the width of the outer shape in the direction orthogonal to the axis 56. The positional relationship between the magnet unit 52 and the rotating shaft 38 as shown in FIG. 7 can be similarly applied to the magnet unit arranged as shown in FIG.

In FIGS. 4, 6 and 7, the magnetic field generated by the outer magnet portion 52 and the inner magnet portion 54 is at least one magnetic field that forms a magnetic field in a region including the center of rotation.
A first magnet assembly (34a in FIG. 2) and a plurality of second magnet assemblies (34b in FIG. 2) arranged annularly together with the magnet and forming a magnetic field in an area outside this area. It can be realized using. The second magnet assembly is arranged in one area on the magnetron unit 30 separated by a plane including the rotation shaft 38.

If the total magnetic amount of the outer magnet portion is made larger than the total magnetic amount of the inner magnet portion, the confinement of plasma is improved. Therefore, plasma can be maintained even when the pressure of the process gas is reduced.

Further, when the plasma confinement property is improved, the electron density in the plasma also increases. When the density of the confined electrons increases, ionization of the particles to be sputtered is promoted. The ionized particles to be sputtered are attracted in the direction of the substrate support 18 according to the potential gradient, so that the velocity component in this direction increases. Therefore, the film thickness uniformity and the bottom coverage are improved.

In addition, since the magnet is arranged in a half area of the sputter target, it is possible to adjust the position thereof to reduce the plasma forming area. Since power can be applied to the reduced area, the plasma density can be increased without increasing the applied power.
As the plasma density increases, so does the electron density,
The ionization of the particles to be sputtered is promoted. Since the ionized sputtered particles are accelerated toward the substrate surface, a large number of sputtered particles having a velocity component directed toward the substrate surface are generated. For this reason, the particles to be sputtered mainly arrive directly below the plasma region, and the film formation proceeds in this arrival region. For this reason, the film thickness uniformity is improved.

Referring to FIGS. 4, 6 and 7, the outer peripheral magnet portion 52 is provided on the outer periphery of a predetermined convex figure. The shape of the magnetic field contributing to confinement of the plasma is defined according to the convex shape. This suppresses a change in the isomagnetic field surface showing the same magnetic field value (in other words, the isomagnetic field line that is the intersection of this surface and a plane parallel to the surface of the substrate). Leakage is suppressed. The convex figure for this purpose is a circle, a substantially circle, an ellipse,
It is preferably substantially elliptical. In order to reduce the leakage of electrons in the plasma, a circular shape is particularly preferable because of high symmetry.

As described above, by adjusting the shape of the isomagnetic field surface (or isomagnetic field line) so as to be suitable for confining electrons, it becomes possible to increase the electron density in the plasma. Therefore, ionization of the particles to be sputtered is promoted. Since the ionized particles to be sputtered are accelerated in the direction of the substrate, the velocity component in this direction increases. Also, if the pressure of the process gas is reduced, the probability of collision between the particles to be sputtered and the process gas atoms can be reduced. Both of these functions act to increase the number of sputtered particles having a velocity component perpendicular to the substrate. Therefore, when the electron density increases, the bottom coverage is improved.

Here, the convex figure is an arbitrary figure existing on a closed outline defining its shape on a plane.
A figure in which the line connecting the points is always on one side of the outline or on the line, and is a figure composed of a straight line, a curve, and at least one of the curves. In particular, a closed curve is called a convex curve. In a convex figure, a straight line is a tangent to the curve at a connection point between the curve and the straight line constituting the figure. In this specification, such a connection between a straight line and a curve is referred to as a smooth connection.

In order to reduce the electron flow flowing to the shield, the study was performed from the viewpoint of the movement of electrons in an electromagnetic field. As a result, even if the magnitude of the magnetic field does not significantly change, if the outer shape of the confinement magnetic field changes significantly, the effect of confining electrons is not sufficiently exhibited. In an electromagnetic field, an electron receives a force in the direction of an electric field and also in a direction related to the velocity of the electron and the direction of a magnetic field.Because the electron moves while drawing a curve in the electric and magnetic fields, for example, However, where the magnetic field is changing significantly, the region where the trajectory of electrons is bent by the magnetic field and reaches
It is possible that the magnetron unit does not generate a magnetic field of sufficient magnitude. For electrons that have reached such a region, the magnetic field of the magnetron unit 30 no longer acts to confine the electrons, and the direction of movement of such electrons cannot be changed. For this reason, such electrons are drawn by the electric field and flow into the shield.

That is, in the magnetron unit 30 shown in FIG. 4, FIG. 6, and FIG. 7, the arrangement of the magnet for generating the magnetic field is considered in consideration of the speed of the electrons (the moving direction of the electrons and the speed of the electrons). It clarifies what to consider and realizes a configuration that does not significantly change the external shape of the magnetic field generated by the magnetron unit spatially.

The sputtering apparatus 10 according to the present embodiment
Has described the case where the subunits are limitedly arranged in a half area of the magnetron unit 30, but the present invention is not limited to such a form. FIG. 8 is a plan view showing a different arrangement of the subunit 34, and shows a cross section corresponding to the II cross section in FIG.
Although various arrangements of the subunit 34 are conceivable, in the present embodiment, the subunit 34 can be arranged in a double annular arrangement as shown in FIG. The all-circular subunits include inner annular subunits 34i groups 64, 66
(The subscript i represents the inner annular arrangement) and the outer annular subunits 34o groups 60, 62 (the subscript o represents the outer annular arrangement).

Next, another embodiment will be described.

FIG. 9 shows a sputtering apparatus 11 according to another embodiment. Members having the same functions as those of the sputtering apparatus 10 shown in FIG. 1 are denoted by the same reference numerals. In FIG. 9, a magnetron unit 31 is provided instead of the magnetron unit 30 in FIG.

Here, FIGS. 10A and 14 show the magnetron unit 31 and the sputter target 16 taken out.

The magnetron unit 31 includes a base plate 33 formed of a magnetic material, a plurality of magnets 43, an inner belt Bin for positioning the magnets 43 in an arrangement position, an outer belt Bout, and a tip of each of the magnets arranged in an annular shape. It is composed of magnetic members 49 and 47 fixed to the portion.

The base plate 33 has a shape in which a circular region and a rectangular region are joined, and each magnet 43 is arranged on the circular region side, and the base plate 33 is driven to rotate near the joint region between the circular region and the rectangular region. Rotating shaft 3
8 is fixed at one end.

The inner belt Bin and the outer belt B
out is used as a positioning member for the magnet 43 and is formed of a non-magnetic material. Openings equal to the outer diameter of the magnet 43 are formed at predetermined intervals in each belt portion. By inserting the magnets 43 into the respective openings, the respective magnets 43 move along the inner belt Bin and the outer belt Bout which are arranged concentrically.
They are arranged in a state of being scattered in two rows of rings. Here, as an example, the magnet 43 on the inner belt Bin side has an S pole, and the magnet 43 on the outer belt Bout side has an N pole.
The poles are arranged so as to face the sputter target 16 respectively. A spacer S made of a non-magnetic material is interposed between the base plate 33 and the inner belt Bin and the outer belt Bout, so that the inner belt Bin and the outer belt Bout are separated from the base plate 33. I have.

The magnets 4 arranged in a ring as described above
3, an annular magnetic member 49 formed by a pole piece, a yoke, or the like is fixed to an end surface (an end surface facing the sputter target 16 side) of each magnet 43 arranged by the inner belt Bin by magnetic force. Thereby, S of each adjacent magnet 43 is determined.
The poles are connected to each other so that a ring-shaped south pole is formed. Similarly, a magnetic member 47 made of a magnetic material is also fixed to an end surface (an end surface facing the sputter target 16 side) of each magnet 43 arranged by the outer belt Bout by a magnetic force. The N poles of the adjacent magnets 43 are connected to each other, so that a ring-shaped N pole is formed. The magnetic member 49 and the inner belt Bin are fixed to the base plate 33 by a fixing pin (not shown) made of a non-magnetic material that penetrates the magnetic member 49 and the inner belt Bin. Are fixed to the base plate 33 by fixing pins (not shown) made of a nonmagnetic material penetrating therethrough.

Thus, a magnetic circuit closed in a donut shape is formed by all the magnets 43 arranged on the inner side and all the magnets 43 arranged on the outer side.

That is, each of the magnetic members 47 and 49 is connected to the S magnetic pole (the first magnetic pole) of the plurality of first magnets 43 included in the inner row.
Magnetic poles) and the N magnetic poles (second magnetic poles) of the plurality of second magnets 43 included in the outer row, and the N magnetic poles of the plurality of first magnets 43 included in the inner row are magnetically coupled. Each magnetically couples and functions as magnetic coupling means for magnetically coupling each of the S magnetic poles of the plurality of second magnets 43 included in the outer row. In other words, the magnetic coupling means is means for magnetically coupling the S magnetic poles of the plurality of first magnets and the N magnetic poles of the plurality of second magnets, and each of the N magnetic poles of the plurality of first magnets. It has one of a means for magnetically coupling and a means for magnetically coupling each of the S magnetic poles of the plurality of second magnets.

In FIG. 10A, the magnet 43
Are illustrated along the circumference of the ellipse, but the present invention is not limited to this example. For example, FIG.
As shown in (b), a configuration in which the magnets 43 are arranged along a circumference closer to a perfect circle may be adopted.
In this case, the inner belt Bin, the outer belt Bou
The corresponding members such as t and the magnetic members 49 and 47 may be formed in an annular shape.

Further, the magnetron unit may be configured as shown in FIG. In this magnetron unit 100, two types of columnar magnets having different diameters are fixed to the surface of a base plate 33 formed of a magnetic material by magnetic force. For example, the diameter of the larger diameter magnet having a larger diameter is about 1.7 cm, and the diameter of the smaller diameter magnet having a smaller diameter is about 1.4 cm. The two magnets have the same height, for example, about 3.3 cm. The magnetic force emitted from the large diameter magnet is about 150 to 200 gauss in a space 2 cm away from one end of the large diameter magnet, and the magnetic force emitted from the small diameter magnet is 60 to 70% of the large diameter magnet.
It is about.

As shown in FIG. 15, six large-diameter magnets 110N are arranged along the circumference on the outer edge of the base plate 33, which is the part farthest from the center of the sputter target 16, and further, Nine small-diameter magnets 120N are arranged on the left and right sides along the same circumference so as to sandwich the large-diameter magnets 110N. Accordingly, the large-diameter magnet 110N and the small-diameter magnet 120N are in a state such that the circular region of the base plate 33 is surrounded by the entirety. In the example of FIG. 15, the large-diameter magnet 110N and the small-diameter magnet 120N have their N poles arranged to face the sputter target 16, and the large-diameter magnet 110N
A magnetic member 130 such as a yoke is formed on the end surface of N and the small-diameter magnet 120N (the end surface facing the sputter target 16) in a ring shape along this arrangement.
Are fixed by magnetic force.

On the other hand, at the center of the base plate 33, ten large-diameter magnets 110S are arranged in an assembled state, and each large-diameter magnet 110S has a state in which the S pole faces the sputter target 16. Has become.
Then, on the end surface of each large-diameter magnet 110S (the end surface facing the sputter target 16), a magnetic member 140 formed of the same material as the magnetic member 130 and having a disk shape so as to cover the gathering region of the large-diameter magnet 110S. Are fixed by magnetic force.

Also in the embodiment shown in FIG. 15, a positioning member (not shown) made of a non-magnetic material, which has been exemplified as the inner belt Bin or the like, is used for the arrangement of the magnets 110N, 110S, and 120N. It is arranged on the surface of the base plate 33 while being positioned by the positioning member.

By configuring the magnetron unit as shown in FIG. 15, the amount of magnetism generated by all the magnets arranged at the outer edge of the base plate 33 can be reduced by the magnetism generated by all the magnets arranged at the center of the base plate 33. It is larger than the amount. As a result, of the high-energy electrons (secondary electrons) emitted from the sputter target 16 by sputtering, the erosion surface 16a
The electrons collected by the magnetic field appearing in the vacuum chamber 12
Can be sufficiently suppressed, and electrons can be effectively confined in a region near the sputter target.

Further, since the magnetic lines of force at the outer edge are larger than those at the center of the base plate 33, the magnetic lines of force extending from the sputter target 16 in the direction of the wafer W do not spread away from the sputter target 16. In order to operate, the sputtering target 16 and the wafer W
The electrons can be effectively confined in the sputtering space formed between them.

Further, by arranging six large-diameter magnets 110N having a large magnetic force on a portion of the base plate 33 farthest from the center of the sputter target 16, that is, on the side wall side of the vacuum chamber 12, the base plate 33 The six large-diameter magnets 110 </ b> N are always positioned on the side wall of the vacuum chamber 12 even when is rotated around the rotation shaft 38. Therefore,
Sputter target 1 on the side wall of vacuum chamber 12
The magnetic lines of force extending toward the wafer W from the outer edge of the vacuum chamber 6 extend toward the center of the vacuum chamber 12 toward the wafer W, and flow out to the shield 26 located on the side wall of the vacuum chamber 12. It reduces the flow of electrons and reduces the flow of electrons.

Further, by arranging the six large-diameter magnets 110N having a large magnetic force at a position on the base plate 33 farthest from the center of the sputter target 16, the generated plasma is generated on the surface of the sputter target 16. Along the side of the vacuum chamber 12, thereby suppressing the tendency of the erosion region to concentrate at the center of the sputter target 16.

In addition, since the magnet is arranged in a half area of the sputter target 16, the position can be adjusted to make the plasma forming area small. Since power can be applied to the reduced area, the plasma density can be increased without increasing the applied power.

The arrangement of the magnets shown in FIGS. 4, 6 and 7 can be applied to the sputtering apparatus 11 as well. Thereby, a desired effect can be obtained. In each of the drawings, the outer magnet 43 arranged along the first magnetic member 47 corresponds to the outer peripheral magnet portion 52, and the inner magnet 43 arranged along the second magnetic member 49 is It corresponds to the magnet unit 54.

In the sputtering apparatus 11, a plurality of first
A unit magnet having a predetermined amount of magnetism can be applied to each of the magnets 43 arranged along the second magnetic members 47 and 49. When the unit magnet is adopted, the magnet unit composed of the first magnetic member and the second magnet unit
The total magnetic amount of each of the ring-shaped magnet portions can be grasped by the number of magnets, and the setting of the total magnetic amount ratio becomes easy.

When the sputter target 16 is separated by a plane including a rotation axis 38 serving as the center of rotation, and one is a first region and the other is a second region, the inner magnet portion is located at the first region. At the same time, the outer magnet portion is located on the boundary between the first and second regions and / or in at least one of the first regions.

[0092] In the magnetron unit 31, it is preferable that the inner magnet portion is provided in the first region, and the outer magnet portion is provided in the first region while passing over the boundary between the first and second regions. Further, the outer magnet portion can pass through a position corresponding to the rotation shaft 38. In particular, in the embodiment shown in FIG. 10, the region between the magnetic member 47 for the outer magnet and the magnetic member 49 for the inner magnet overlaps only with the first region.

By arranging the magnets 43 in this manner, the area on the erosion surface 16a where plasma is formed can be reduced. Since power can be applied to the reduced area, the plasma density can be increased without increasing the applied power. As the plasma density increases, the electron density also increases, which promotes ionization of the particles to be sputtered. Since the ionized particles to be sputtered are accelerated toward the surface of the wafer W, a large number of particles to be sputtered having a velocity component directed toward the surface of the wafer W are generated. For this reason, the particles to be sputtered mainly arrive directly below the plasma region, and the film formation proceeds in this arrival region. Therefore, the film thickness uniformity is improved, and the bottom coverage is also improved.

[0094] In the sputtering apparatus 11, each magnet section can be arranged to provide a magnetic field along a respective closed line. In the vicinity of the erosion surface 16a, plasma is generated in a region between the closed lines. That is, the shape and area of the region where the plasma is generated are defined by the two closed lines. The closed line can be a closed curve.
Also, the closed line can be a convex curve. These curves can be provided in the first region of the magnetron unit and can also pass through the axis of rotation 38.

In the magnetron unit 31, when the outer magnet portion is provided on the outer periphery of a predetermined convex figure on the magnetron unit 31, the shape of the magnetic field contributing to the generation of plasma is defined by the convex figure. The range of change of the bending of the isomagnetic field line based on the closed convex curve which is the outer peripheral line of the convex figure can be made smaller than the range of change of the bending of the closed curve. Thereby, the leakage of electrons from the plasma is reduced, and the electrons are efficiently confined.

When the electron density increases, ionization of the particles to be sputtered is accelerated. Since the ionized particles to be sputtered are accelerated in the direction of the substrate, the velocity component in this direction increases. Further, when the electron density in the plasma increases, the pressure of the process gas can be reduced. Since the probability of collision between the particles to be sputtered and the process gas atoms is reduced by lowering the pressure, the number of particles to be sputtered having a velocity component perpendicular to the substrate increases. For these reasons, bottom coverage is improved. The outer magnet portion is preferably made of a magnet disposed on the outermost periphery. by this,
Electrons can be confined inside the outermost magnet part.

FIG. 11 schematically shows the magnetic field generated by the magnetron unit 31 when the total magnetic amount of the inner peripheral magnet portion is smaller than the total magnetic amount of the outer peripheral magnet portion. FIG. 12 schematically shows the magnetic field generated by the magnetron unit 31 when the relationship between the total magnetic quantities in FIG. 11 is reversed.

In the sputtering apparatus shown in FIG. 11, the lines of magnetic force (indicated by broken lines in the figures) from the N pole of the magnet 43 included in the outer peripheral magnet portion (52 in FIGS. 4, 6 and 7) are generated by the magnetron unit 31. Extends toward the center. Part of the magnetic field reaches the S pole of the magnet 43 and passes through the inside 41 of the magnetic member constituting the magnetic circuit and closes. The remaining magnetic field extends toward the center of the magnetron unit 31 to the vicinity of the central axis, and then changes its direction in the axial direction and extends to the opposite side of the magnetron unit 31. For this reason, the magnetic field from the outer peripheral magnet is reduced by the magnetron unit 31 near the erosion surface 16a.
Facing the inside. In response to the bending of the magnetic field, the direction of movement of the electrons is directed inside the magnetron unit 30. Therefore, the electron flow flowing to the shield 26 can be reduced.

On the other hand, as schematically illustrated in FIG.
Assuming that the total magnetic amount of the inner magnet portion 80 (S-pole) provided on the inner side is larger than the total magnetic amount of the outer magnet portion 81 (N-pole) provided on the outer side, magnetic lines of force extending from the inner magnet portion 80. (Indicated by a broken line in the drawing) is a state that extends outside the range surrounded by the outer magnet portion 81. Therefore, such a magnetic field has a weak effect of confining the plasma.

In the sputtering apparatus described above, the magnetron units 30 and 31 are formed in the space in the vacuum chamber 12 between the erosion surface 16a and the upper surface 18a of the pedestal 18 (hereinafter referred to as sputtering space). Respectively governs the shape of the applied magnetic field H. According to the magnetron units 30 and 31, a magnetic field suitable for confining electrons in the sputtering space is generated. Since the magnetron units 30 and 31 are rotated by the drive motor 36, the magnetic field generated by each magnet is
At 0 and 11, around the rotation axis 38, for example, 60 to 1 per minute
It rotates at a frequency of about 00 times.

When the process gas from the magnetron units 30 and 31 is turned into plasma near the erosion surface 16a, the erosion surface 16
Particles to be sputtered are generated from a. By adopting the configuration of the magnetron unit corresponding to FIGS. 2, 4, 6, 7, 10 (a) and 10 (b), it is possible to reduce the pressure required to maintain the plasma. it can. In addition, if the region where plasma is generated is reduced, the plasma density can be increased. Thereby, the electron current density can be increased. Therefore, ionization of the particles to be sputtered is promoted. The ionized particles to be sputtered are accelerated in the direction of the substrate support 18. Therefore, the velocity component in the direction along the axis that intersects the substrate W becomes relatively large with respect to the velocity component in the direction orthogonal to the axis, and bottom coverage is improved. Further, when the velocity component perpendicular to the substrate W increases, the film formation proceeds immediately below the rotating magnetron units 30 and 31 and a film with good bottom coverage is formed.

In such a sputtering apparatus,
According to the results of experiments conducted by the inventor, the conventional apparatus having a film thickness uniformity of 10% or more can be suppressed to 5% or less by applying the present invention. here,
The film thickness uniformity is (measured value at the thickest point of the film thickness−measured value at the thinnest point of the film thickness) / (average value of the film thickness) / 2 × 10
Defined as 0.

According to the experiment performed by the inventor in the sputtering apparatus described above, in practice, the total magnetic amount of the outer magnet portion is equal to 1.times. The total magnetic amount of the inner magnet portion.
It has been found that a setting of 5 times or more is preferable.

FIG. 13 shows a measurement result in which the horizontal axis indicates the total magnetic quantity ratio and the vertical axis indicates the uniformity of the sheet resistance Rs.

This measurement was performed under the following conditions: target: Ti power: 12 kW, pressure: 6.67 × 10 ⁻² Pa (0.5 mT), film thickness: 100 nm.

According to FIG. 13, if the total magnetic quantity ratio is smaller than 1.5, the Rs uniformity tends to deteriorate, while if the total magnetic quantity ratio is 1.5 or more, as the total magnetic quantity ratio increases, Rs uniformity is improved.

In the conventional sputtering apparatus, the pressure of the process gas is set to 0.0
When the pressure was less than 5 Pa (0.375 mTorr), plasma could not be maintained. However, in the sputtering apparatus described above, the minimum discharge maintaining voltage is set to 0.02 Pa (0.15 m
Torr). At such a low pressure, the bottom coverage can be improved 1.5 times or more as compared with the conventional case.

As described above, FIGS. 2, 4, 6, and
FIGS. 7, 10A and 10B show forms of magnet arrangement applicable to the first and second embodiments. In these embodiments, the magnet portion, for example, the magnet portion 52 is provided along a predetermined closed curve, for example, along the shape of a pole piece.

In such a magnetron unit, the minimum radius of curvature of the closed curve is preferably at least 0.8 times the maximum radius of curvature, and the minimum radius of curvature of the convex curve is at least 0.8 times the maximum radius of curvature. The inventor considers that the following is preferable. If the outer magnet portion is arranged along a predetermined closed curve, the shape of the magnetic field contributing to the generation of plasma is defined by the closed curve. Since the isomagnetic field lines are bent in the above range of the radius of curvature, leakage of electrons from the plasma, which may be caused by the bend of the isomagnetic field curve, is reduced. If the inner magnet also satisfies the condition regarding the radius of curvature as described above, more favorable results can be obtained. In particular, the magnet arrangement shown in FIG. 10 (b) produces the most favorable results.

When the magnetron unit as described above is prepared, electrons in the plasma can be efficiently confined due to the electron confinement effect by the magnetic field. Therefore, the electron density can be increased. As the electron density increases, the sputtered particles become ionized. Since the ionized sputtered particles are accelerated by the electric field, the number of sputtered particles moving in the direction from the target to the substrate increases.

Further, since the pressure of the process gas can be reduced, the frequency of collision of the process gas particles with the sputtered particles is reduced, so that the bottom coverage ratio is further improved.

The present invention has been described based on the embodiments. However, the present invention is not limited to such embodiments, and various modifications are possible. For example, the target material to which the sputtering apparatuses 10 and 11 of the present embodiment can be applied is not limited to copper (Cu), but may include other elements, titanium (Ti), aluminum (Al), and alloys thereof. Etc. can also be applied.

[0113]

As described above in detail, in the sputtering apparatus according to the present invention, the magnetron unit includes the first magnet section and the second magnet section provided to generate a magnetic field in the vacuum chamber. Have. The second magnet section is disposed outside the first magnet section. The total magnetic amount of the first magnet unit is smaller than the total magnetic amount of the second magnet unit.

As a result, the amount of magnetic flux extending outside the vacuum chamber is reduced, so that the confinement of electrons is improved.

In the film forming method according to the present invention, the film is formed by generating a magnetic field having excellent electron confinement.

Accordingly, a sputtering apparatus and a film forming method capable of improving the bottom coverage are provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a magnetron type sputtering apparatus according to a first embodiment.

FIG. 2 is a plan view showing an arrangement position of a subunit according to the first embodiment.

FIG. 3 is an enlarged view of a magnetron unit in which a subunit portion is enlarged.

FIG. 4 is a plan view showing a magnet arrangement for explaining a magnetic field generated by a subunit.

FIG. 5 is a plan view showing a magnet arrangement for explaining a magnetic field generated by a subunit.

FIG. 6 is a plan view showing a magnet arrangement for explaining a magnetic field generated by a subunit.

FIG. 7 is a plan view showing a magnet arrangement for explaining a magnetic field generated by a subunit.

FIG. 8 is a plan view of the magnetron unit showing the arrangement of the subunits.

FIG. 9 is a schematic configuration diagram of a magnetron type sputtering apparatus according to a second embodiment.

FIGS. 10 (a) and 10 (b) are explanatory views showing a positional relationship between a magnet and a base plate and a sputter target in the magnetron unit of FIG. 9 in a plan view.

FIG. 11 is a configuration diagram showing a magnetic field formed in a sputtering apparatus.

FIG. 12 is a configuration diagram showing a magnetic field formed in a sputtering apparatus.

FIG. 13 is a characteristic diagram illustrating a relationship between a total magnetic amount ratio between an outer peripheral magnet and an inner magnet and Rs.

FIG. 14 is an exploded perspective view showing the magnetron unit shown in FIG. 9;

FIG. 15 is a plan view illustrating a positional relationship between a magnet and a base plate of a magnetron unit according to another embodiment and a sputter target.

[Explanation of symbols]

10, 11: sputtering device, 12: vacuum chamber 13a, 13b: insulating member, 14: housing, 15 ...
Substrate 16 ... Sputter target, 18 ... Pedestal, 20
... exhaust port 21 ... vacuum pump, 22 ... supply port, 23 ... valve,
24: Acceleration power supply 25: Process gas supply source, 26: Shield, 29: Controller 30, 31, 100: Magnetron unit, 32, 3
3 Base plate 30, 32, 34 Magnet 36 Drive motor 38 Rotating shaft 40 Yoke member 42 43 43 44
Bar magnets 47, 48, 49, 50: magnetic member 52: first magnet portion, 54: second magnet portion

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tsune Aida 14-3 Shinizumi, Narita-shi, Chiba Pref. Nogehira Industrial Park Applied Materials Japan Co., Ltd. Applied Materials Japan Co., Ltd. (72) Inventor Yoon Ki-Hun 14-3 Shinsen, Narita-shi, Chiba Pref. Applied Materials Japan Co., Ltd.

Claims (11)

[Claims] A vacuum chamber; a pressure reducing means for reducing the pressure in the vacuum chamber; a gas supply means for supplying a process gas into the vacuum chamber; and a substrate for supporting a substrate in the vacuum chamber. A support portion, comprising: a sputter target provided such that an erosion surface faces the substrate support portion; and a magnetron unit provided on a side opposite to the substrate support portion with respect to the sputter target, wherein the magnetron unit includes: A first magnet unit and a second magnet unit provided to generate a magnetic field in the chamber, wherein the second magnet unit is disposed outside the first magnet unit; The total magnetic amount of the magnet unit is smaller than the total magnetic amount of the second magnet unit. 2. The first magnet section includes a plurality of first magnets arranged with a portion indicating a first magnetic pole facing the target, and the second magnet section includes:
The sputtering apparatus according to claim 1, further comprising a plurality of second magnets having a portion indicating a second magnetic pole facing the target. 3. The apparatus according to claim 1, wherein the magnetron unit includes a plurality of first magnetron units.
3. The sputtering apparatus according to claim 2, wherein each of the first magnetic members supports one of the plurality of first magnets and one of the plurality of second magnets. 4. 4. The magnetron unit according to claim 2, wherein the magnetron unit has a second magnetic member, and the second magnetic member supports the plurality of first magnets and the plurality of second magnets. The sputtering apparatus as described in the above. 5. The sputtering apparatus according to claim 4, wherein said second magnetic member is a base plate of said magnetron unit. 6. The sputtering apparatus according to claim 3, wherein the plurality of second magnets are annularly arranged so as to surround the plurality of first magnets. 7. The plurality of second magnets, wherein the magnetron unit is provided with a third magnetic member provided to connect portions of the plurality of first magnets indicating first magnetic poles, and
The sputtering apparatus according to any one of claims 3 to 5, further comprising: a fourth magnetic member provided so as to connect portions indicating the second magnetic pole of the magnet. 8. The first magnet section has one end indicating a first magnetic pole and the other end indicating a second magnetic pole. The first magnet section includes a plurality of first magnets arranged with the one end facing the target. The second magnet section has one end indicating a second magnetic pole and the other end indicating a first magnetic pole, and is disposed in an annular shape outside the plurality of first magnets with the one end facing the target. The magnetron unit includes a plurality of first magnetic members, a third magnetic member, and a fourth magnetic member, and each of the first magnetic members includes a magnetic circuit. The other end of the plurality of first magnets and the other end of the plurality of second magnets are respectively supported so as to constitute the third magnet,
The plurality of first magnets are provided in an annular shape so as to connect the one ends of the plurality of first magnets, and the fourth magnetic member is connected to the plurality of second magnets.
2. The magnet according to claim 1, wherein the second magnet portion has a total magnetic amount that is 1.5 times or more the total magnetic amount of the first magnet portion. 3. The sputtering apparatus according to claim 1. 9. The first magnet unit has one end indicating a first magnetic pole and the other end indicating a second magnetic pole, and a plurality of first magnets arranged annularly with the one end facing the target.
Wherein the second magnet portion has one end indicating a second magnetic pole and the other end indicating a first magnetic pole, with the one end facing the target and being annular outside the plurality of first magnets. The magnetron unit supports the other end of the plurality of first magnets and the other end of the plurality of second magnets so as to form a magnetic circuit. A second magnetic member,
A third magnetic member provided annularly so as to connect the one ends of the plurality of first magnets, and a plurality of second magnetic members;
A fourth magnetic member provided in an annular shape so as to connect the one ends of the magnets, wherein the second magnet portion has a total magnetism that is 1.5 times or more the total magnetism of the first magnet portion. The sputtering apparatus according to claim 1, wherein the sputtering apparatus has an amount. 10. The sputtering apparatus according to claim 1, wherein each of the plurality of first and second magnets is a unit magnet having a predetermined amount of magnetism. 11. A step of arranging a substrate so as to face a target, a step of introducing a process gas into a vacuum chamber, and a step of directing a first magnetic pole to the target and a second magnetic pole to a magnetic member. A first magnet section provided, and a second magnet section annularly arranged outside the first magnet section with a second magnetic pole directed to the target and a first magnetic pole provided toward the magnetic member. Magnet part,
And the total magnetic amount of the first magnet part is the second magnetic part.
A method of generating plasma using a magnetron unit smaller than the total amount of magnets of the magnet part, and a step of forming a film by depositing sputtered particles on the substrate.