JP3649933B2 - Magnetron sputtering equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a magnetron sputtering apparatus, and more specifically, a magnetron cathode capable of forming a thin film having a uniform thickness and film quality on a surface of a stationary rectangular substrate using a rectangular target larger than the effective film forming area of the substrate. The present invention relates to a magnetron sputtering apparatus provided with an electrode.
[0002]
[Prior art]
  In recent years, there has been a demand for an apparatus capable of forming a uniform film thickness distribution on a large-area substrate and capable of forming a uniform film for manufacturing a liquid crystal display device. A magnetron sputtering apparatus is often used as the film forming apparatus.
[0003]
  A basic configuration of a general magnetron sputtering apparatus will be described with reference to FIG.
[0004]
  The magnetron sputtering apparatus has a configuration in which a substrate 102 to be deposited in a vacuum chamber 101 and a target 103 which is a thin film base material are arranged facing the substrate 102.
[0005]
  The target 103 is joined to a backing plate 104 cooled by cooling water or the like by a low melting point metal (solder) (not shown) such as indium. The backing plate 104 increases the temperature due to ion bombardment during sputtering. It is suppressed.
[0006]
  A magnetic circuit 105 is installed on the back side of the backing plate 104 so as to generate a tunnel-shaped poloidal magnetic field on the surface of the target 103.
[0007]
  When a negative potential is applied to the target 103 by the power source 106 in a state where a tunnel-shaped poloidal magnetic field is generated by the magnetic circuit 105, the surface of the target 103 is bombarded with ions in the plasma. At this time, since secondary electrons emitted by the γ action are captured by the poloidal magnetic field, a closed annular (hereinafter referred to as racetrack) high-density plasma is formed along the tunnel-shaped poloidal magnetic field.
[0008]
  The ions in the high-density plasma are accelerated toward the target 103 by the electric field of the ion sheath generated near the surface of the target 103, collide with the target 103, and scatter the material constituting the target 103. At the same time, secondary electrons are also emitted from the surface of the target 103 by the γ action.
[0009]
  The particles scattered from the surface of the target 103 adhere to and deposit on the surface of the substrate 102 facing the target 103 to form a thin film.
[0010]
  In this magnetron sputtering apparatus, local high-density plasma can be generated in a racetrack shape, so that high-speed film formation and temperature rise of the substrate can be suppressed.
[0011]
  However, in the magnetron sputtering apparatus having the above configuration, the in-plane distribution of the thickness and film characteristics of the thin film formed on the substrate 102 is generated, reflecting that the target 103 is locally consumed.
[0012]
  Accordingly, various techniques have been proposed for making the thickness of the thin film formed on the substrate 102 uniform and for effectively using the target 103 with uniform consumption. Such a technique is roughly classified into a case where the substrate 102 on which a film is to be formed by sputtering, for example, is circular and a rectangle. Basically, in either technique, the target 103 is uniformly consumed and formed on the substrate 102 by intentionally moving the magnetic circuit 105 disposed on the back surface of the backing plate 104 that holds the target 103. We are trying to obtain the uniformity of film thickness and film quality.
[0013]
  That is, in order to make the thickness of the thin film formed on the substrate 102 uniform or to use the target 103 evenly and effectively, the magnetic circuit 105 is placed on the surface of the target 103 when the substrate 102 is circular. The magnetic circuit 105 may be reciprocated in a plane substantially parallel to the surface of the target 103 if the substrate 102 is rectangular.
[0014]
  Here, a magnetron sputtering apparatus for forming a thin film on a substrate surface using a rectangular target larger than the effective film formation area of the substrate when the substrate on which a film is to be formed is rectangular will be described. In this magnetron sputtering apparatus, a magnetic circuit as a magnetic field generating means is reciprocated in a plane substantially parallel to the target surface.
[0015]
  First, a magnetron sputtering apparatus in which a magnetic circuit unit, which is a magnetic field generating means, is configured by a single magnetic circuit will be described below with reference to FIGS. 15 and 16.
[0016]
  FIG. 15 is a cross-sectional view of a main part of a film forming chamber of a magnetron sputtering apparatus disclosed in Japanese Patent Application Laid-Open No. 6-10127. FIG. 16 is a perspective view of the main part of the film forming chamber of the magnetron sputtering apparatus disclosed in Japanese Patent Application Laid-Open No. 9-31646.
[0017]
  In the magnetron sputtering apparatus shown in FIG. 15, a magnet apparatus 113 as a magnetic circuit unit constituted by one magnetic circuit is disposed on the back side of a backing plate 111 with a target 112 attached to the surface. A moving means 114 for moving the magnet device 113 along the back surface of the backing plate 111 is attached to the magnet device 113.
[0018]
  At this time, the magnet device 113 moves until the high-density plasma protrudes between the one end portion and the other end portion of the target 112 at each end portion. Further, at the time of sputtering, excitation by light irradiation and supply of thermoelectrons are performed so that the plasma does not become unstable at each end of the target 112.
[0019]
  Further, the magnetron sputtering apparatus shown in FIG. 16 has a magnetic field generating means 211 as a magnetic circuit unit composed of one magnetic circuit movable in the direction of the arrow on the back surface of a backing plate 215 to which a target (not shown) is attached. 15 is the same as the magnetron sputtering apparatus shown in FIG. 15, but a rib 215a is provided on the surface opposite to the target mounting surface of the backing plate 215 so as not to mechanically interfere with this. Is different in that the magnetic field generating means 211 is provided with relief.
[0020]
  As described above, the rib 215a is provided on the backing plate 215, so that the mechanical strength can be ensured without forming the backing plate 215 thick.
[0021]
  In addition, when the backing plate 215 is enlarged as the size of the substrate to be sputtered increases, it is necessary to increase the thickness in order to prevent the target on the backing plate 215 from being deformed by atmospheric pressure. By providing the ribs 215a, the deformation of the target due to atmospheric pressure can be suppressed without increasing the thickness of the backing plate 215.
[0022]
  Further, in order to suppress the deformation of the target due to the atmospheric pressure, Japanese Patent Application Laid-Open No. 5-132774 discloses a magnetron sputtering apparatus provided with means for evacuating the space containing the magnetic field generating means. In this magnetron sputtering apparatus, as shown in FIG. 17, the backing plate 304 to which the target 309 is attached is thinned to bring the magnetic field generating means 305 and the surface of the target 309 closer to each other, and a strong magnetic field is obtained on the surface of the target 309. .
[0023]
  Subsequently, a magnetron sputtering apparatus in which a magnetic circuit unit, which is a magnetic field generating means, includes a plurality of magnetic circuits will be described below with reference to FIGS. 18 (a) to (c) to FIGS. 22 (a) to (c). explain.
[0024]
  FIGS. 18A to 18C and FIGS. 19A to 19C are explanatory views of a magnetron sputtering apparatus disclosed in Japanese Patent Laid-Open No. 6-192833.
[0025]
  FIG. 18A schematically shows a magnetron sputtering apparatus provided with a magnetic circuit unit 403 in which a plurality of magnetic circuits 403 a... Having the same magnetic field strength are arranged for a set of target 401 and backing plate 402. It is sectional drawing.
[0026]
  FIG. 18B shows a magnetic circuit unit 413 configured such that the magnetic field strength in the magnetic circuit 413 a corresponding to both side portions of the target 401 is stronger than the magnetic field strength in the magnetic circuit 413 b corresponding to the center portion of the target 401. It is a schematic sectional drawing of the magnetron sputtering device provided with.
[0027]
  18C, similarly to the magnetron sputtering apparatus shown in FIG. 18B, the magnetic field strength in the magnetic circuit 423a corresponding to both side portions of the target 401 is the magnetic field in the magnetic circuit 423b corresponding to the central portion of the target 401. It is a schematic sectional drawing of the magnetron sputtering device provided with the magnetic circuit unit 423 comprised so that it might become stronger than intensity | strength.
[0028]
  FIG. 19A is a plan view of a magnetic circuit unit 433 in which magnetic shields 434 and 435 are formed between and around each of the magnetic circuits 433a...
[0029]
  FIG. 19B is a plan view of the rectangular target 431 eroded by the magnetic circuit unit 433 shown in FIG. Here, a state in which the target 431 is eroded while the magnetic circuit unit 433 is stationary is shown, and the eroded portion 431a has a racetrack shape. In this case, the magnetic strengths of the magnetic circuits 433a of the magnetic circuit unit 433 are all the same.
[0030]
  FIG. 19C is a cross-sectional view of the target 431 shown in FIG. In this case, since the magnetic strength of each magnetic circuit 433a in the magnetic circuit unit 433 is the same, the depth of each erosion portion 431a of the target 431 is the same.
[0031]
  By the way, in the state where the magnetic circuit unit 433 is stationary as described above, only the portion corresponding to the magnetic circuit 433a is eroded, so that the magnetic circuit unit 433 is as shown in FIG. If the target 431 is moved in the direction of the arrows X and Y indicating the longitudinal direction of the target 431, the target 431 can be eroded almost uniformly as in the eroded portion 431b shown by the one-dot chain line in FIG.
[0032]
  20 (a) and 20 (b) show the magnetic field generating means of the magnetron sputtering apparatus disclosed in Japanese Patent Laid-Open No. 8-134640. FIG. 4A is a perspective view of a magnetic circuit unit 501 composed of a single magnetic circuit 501a, and FIG.
It is a top view of the magnetic circuit unit 511 which combined the air circuit 511a ....
[0033]
  In the magnetron sputtering apparatus disclosed in the above publication, for example, as shown in FIG. 20B, the magnetic circuit unit 511 is reciprocated in the direction of the arrows X and Y, which is the longitudinal direction of a rectangular target (not shown). When the consumption and the thickness distribution of the thin film caused thereby are within a desired range, the magnetic field strength is weakened in the region of the target surface corresponding to the magnet portion 512 constituting the outer peripheral portion of each magnetic circuit 511a. There is a need to.
[0034]
  For this reason, in the magnetic circuit unit 501 shown in FIG. 20A, the height of the magnet portion 502 constituting the outer peripheral portion of the magnetic circuit 501a is made lower than the magnet portion 503 in the central portion, thereby the magnetic circuit 501a. The magnetic field strength in the region of the target surface corresponding to the outer peripheral portion of is reduced.
[0035]
  On the other hand, in the magnetic circuit unit 511 shown in FIG. 20B, the distance (GA, GB) between the magnet portion 512 constituting the outer periphery of the magnetic circuit 511a and the central magnet 513 at the center is increased, and the magnetic circuit unit 511 shown in FIG. The magnetic field strength in the region of the target surface corresponding to the outer peripheral portion of the magnetic circuit 511a is reduced.
[0036]
  FIGS. 21A and 21B show side views of the magnetic field generating means of the magnetron sputtering apparatus disclosed in Japanese Patent Laid-Open No. 8-199354. FIG. 4A is a cross-sectional view of the main part including a surface perpendicular to the longitudinal direction of the magnetic circuit unit 601, and FIG. 4B is a cross-sectional view of the main part including a surface perpendicular to the short direction of the magnetic circuit unit 601. Is shown.
[0037]
  As shown in FIG. 21A, the magnetic circuit unit 601 is composed of a plurality of magnetic circuits 601a... And the interval between the magnetic circuits 601a can be adjusted independently. As shown in FIG. 21 (b), it can be freely inclined in the long side direction.
[0038]
  As a result, when the magnetic circuit unit 601 as the magnetic field generating means is reciprocated to attempt to keep the target 602 non-uniformly consumed and the thickness distribution of the thin film caused thereby, within a desired range, it cannot be adjusted. The non-uniformity of the thickness of the thin film due to the plasma asymmetry is compensated for the plasma asymmetry by tilting the magnetic circuit 601 a in conjunction with the reciprocating motion of the magnetic circuit unit 601.
[0039]
  FIGS. 22A to 22C show a magnetron sputtering apparatus disclosed in Japanese Patent Laid-Open No. 9-125242. 4A is a cross-sectional view of the main part of the film forming chamber 700 of the magnetron sputtering apparatus, and FIG. 4B is a plan view of the magnetic field generating means 702 of the magnetron sputtering apparatus arranged in the film forming chamber 700. c) adjusts the magnetic field strength on the surface of the target 701 by adjusting the distance between the magnetic pole surfaces of the five magnet units 703 constituting the magnetic field generating means 702 and the target 701, and consequently the thickness of the thin film formed on the substrate 704. It is sectional drawing which shows arrangement | positioning of each magnet unit 703 in the case of adjusting thickness distribution.
[0040]
  The magnetron sputtering apparatus having the above-described configuration includes magnetic field generating means as disclosed in Japanese Patent Laid-Open No. 6-192833 shown in FIGS. 18 (a) to 18 (c) and FIGS. 19 (a) to 19 (c). In addition to the magnetic circuit configuration for increasing the magnetic field strength generated on the target surface by the magnetic circuits at both ends of the plurality of magnetic circuit units, the magnetic field strength generated on the target 701 surface by the magnet unit 703 located at the center is increased. And a configuration of an end portion of the magnet unit 703 for suppressing the uneven wear of the target 701 accompanying therewith are disclosed.
[0041]
[Problems to be solved by the invention]
  However, the following problems occur in each of the conventional configurations described above.
[0042]
  (A) In the magnetron sputtering apparatus shown in FIGS. 15 and 16, the magnetic field generating means is constituted by a single magnet unit, so that the thickness of the thin film formed on the substrate is uniform. It is necessary to reciprocate the magnet unit over the entire width of the target.
[0043]
  Further, in order to increase the deposition rate, it is necessary to increase the input power for generating plasma. However, if the input power is increased too much, the ion current density that bombards the target becomes too large, and from the glow discharge that causes the sputtering action (secondary electron emission by γ action is necessary for maintaining the discharge), The discharge form changes to arc discharge (an electron supply source in which thermionic emission is necessary for sustaining the discharge). That is, the input power density cannot be increased beyond a certain value.
[0044]
  Therefore, the occurrence of the above-mentioned adverse effects due to the increase in input power and the necessity of reciprocating the magnet unit described above over the entire width of the target result in a single target when a considerably large target is used with respect to the width of the magnet unit. An extremely large amount of electric power cannot be supplied to the racetrack-shaped high-density plasma obtained with the magnet unit of this type, and there is a limit to improving the film formation rate for the purpose of improving the apparatus performance.
[0045]
  Furthermore, in order to make the thickness distribution of the thin film formed on the substrate uniform, it is necessary to control the speed of the reciprocating motion of the magnet unit according to the relative position with respect to the target, which requires a complicated control system.
[0046]
  (B) In the magnetron sputtering apparatus shown in FIG. 16, the rib 215a is provided on the backing plate 215. When the target is bonded to the backing plate 215 with a low melting point solder such as indium, the following is performed. A problem occurs.
[0047]
  In general, the backing plate 215 is made of a copper-based material having good thermal conductivity in order to suppress an increase in target temperature due to ion bombardment of the target during sputtering. The target is bonded to the backing plate 215 with indium-based low-temperature solder, and then cooled by directly or indirectly cooling (usually water cooling) the backing plate 215.
[0048]
  Since the target is a material different from the backing plate 215 (a thin film material to be formed on the substrate itself, or a material for forming a thin film by reactive sputtering), there is a difference in thermal expansion. When the target and the backing plate 215 are bonded with indium-based low-temperature solder (melting point: about 150 ° C.) in this state, warpage occurs as a whole due to the difference in thermal expansion. Although it is assumed that the material of the backing plate 215 has the same thermal expansion as that of the target, and there is an attempt to eliminate the warp while sacrificing heat conduction, it is not preferable from the viewpoint of the cost of the material and the cost of processing. .
[0049]
  In addition, the magnetron sputtering apparatus shown in FIG. 16 can also reduce the warping of the backing plate 215 due to the bonding of the target, but in reality, the thermal stress due to the difference between thermal history and thermal expansion during bonding remains as it is. A large stress is applied to the target surface. In particular, when the target is a ceramic material whose thermal expansion is smaller than that of a copper-based material, a large tensile stress remains on the target surface, which is not preferable for the mechanical strength of the target.
[0050]
  When using a flat plate-type backing plate without ribs, maintain the form in which the backing plate is positively bent at a suitable temperature for a certain period of time when the temperature of the target bonding process drops. It is also possible to perform a process of causing the plastic flow of the solder and reducing the warpage of the entire target while relaxing the thermal stress. However, if the backing plate has ribs as described above, the degree of freedom in this process is reduced.
[0051]
  Further, the publication that discloses the magnetron sputtering apparatus of FIG. 16 only describes that the weight of the backing plate 215 is reduced for the purpose of thinning the backing plate 215, and there is no description regarding the magnetic field strength of the target surface. .
[0052]
  (C) In the magnetron sputtering apparatus shown in FIG. 17, the pressure in the space for accommodating the magnetic field generation means 305 is not defined, and the outer wall of the space for accommodating the magnetic field generation means, the magnetic field generation means 305, or the magnetic field generation means. Since the potential of the drive mechanism is not defined, simply exhausting the space containing the magnetic field generation means to reduce the pressure difference from the atmospheric pressure will cause the geometrical arrangement and each part in that space to be exhausted. Depending on the potential of the substrate, the electric discharge between the backing plate 304 and the magnetic field generating means 305, the magnetic field generating means moving mechanism, etc. may cause not only the loss of power input for sputtering, but also a mechanical failure. End up.
[0053]
  Here, “simply” is used to mean the degree of exhaust when only the deformation of the backing plate 304 due to the pressure difference from the atmospheric pressure is taken into account when the space containing the magnetic field generating means 305 is exhausted. . Therefore, as the exhaust pump for exhausting the space accommodating the magnetic field generating means 305, an oil rotary pump or a pump capable of exhausting to about several Pa such as a combination of an oil rotary pump and a mechanical booster pump is used. Such a pump is preferably selected from the viewpoint of equipment cost and maintenance.
[0054]
  However, when these pumps are used as exhaust pumps, the space in which the magnetic field generating means 305 is accommodated has a pressure of about several Pa, and the potential of the magnetic field generating means 305, the magnetic field generating means driving mechanism, etc. If the plate 304 is not the same as the plate 304 and is grounded, for example, when a high voltage is applied to the backing plate 304 to which the target 309 is bonded for sputtering, unnecessary discharge occurs not only on the surface of the target 309 as described above. Resulting in.
[0055]
  In order to avoid this, when the space accommodating the magnetic field generating means is evacuated, the ultimate pressure is 10^-3Using, for example, a turbo molecular pump or a cryopump that is lower than about Pa is disadvantageous in terms of cost.
[0056]
  (D) In the magnetron sputtering apparatus shown in FIGS. 18 (a) to 18 (c) to 22 (a) to (c), the effects obtained by the individual specific means are expected to be disclosed in the respective publications. it can. However, the dimensions of the plurality of magnet units constituting the magnetic field generating means and the amplitude of the reciprocating motion of the magnetic field generating means still have a problem for the purpose of “suppressing uneven consumption of the target”.
[0057]
  In the magnetron sputtering apparatus disclosed in Japanese Patent Laid-Open No. 6-192833 described with reference to FIGS. 18A to 18C and FIGS. 19A to 19C, the amplitude of the reciprocating motion of the magnetic field generating means is one magnetic field. It is assumed that the width of the circuit unit 403 is almost equal to the width in the short side direction. The reciprocating motion changes the speed in a sine wave shape.
[0058]
  At this time, when the magnetic circuit unit 403 shown in FIGS. 18A to 18C is stopped, the target 401 is in an erosion state as shown in FIG. In the figure, a portion where the concave portion is eroded is shown.
[0059]
  Then, the erosion situation when the magnetic circuit unit 403 is reciprocated is as shown in FIGS. Here, P1 to P4 in FIGS. 23B to 23E indicate the amplitudes when the magnetic circuit unit 403 reciprocates, indicating that the amplitudes gradually increase. When the amplitude shown in FIG. 23 (e) is P4, the width of one magnetic circuit 403a of the magnetic circuit unit 403 is almost equal to the width in the short side direction. That is, the target 401 is not evenly eroded, and the portion where the erosion proceeds and the portion where the erosion does not progress are distributed in the form of vertical stripes.
[0060]
  Therefore, the utilization efficiency of the target 401 is determined at the portion where erosion progresses most. Further, in this state, the thickness distribution of the thin film formed on the substrate also becomes a vertical stripe distribution reflecting the erosion status of the target 401.
[0061]
  (E) In the magnetron sputtering apparatus disclosed in Japanese Patent Application Laid-Open No. 8-134640 described with reference to FIGS. 20A and 20B, the amplitude of the reciprocating motion of the magnetic circuit unit 511 is in the short side direction of one magnetic circuit 511a. It is set to be equal to about half the width. Further, the speed in the reciprocating motion of the magnetic circuit unit 511 is changed in a sine wave shape.
[0062]
  Since the above publication does not disclose the target erosion situation obtained when the magnetic circuit unit 511 is stationary, the target erosion situation when the magnetic circuit unit 511 is discharged by reciprocating motion is not necessarily clear, Since the dimensions of the single magnetic circuit 511a and the parallel pitch of the magnetic circuits 511a are not defined, target erosion does not always proceed uniformly. Furthermore, there is a difference in the time during which the target is exposed to high-density plasma by the amount that the reciprocating motion has a sinusoidal speed change, and target erosion tends to proceed at both ends of the amplitude of the reciprocating motion.
[0063]
  The distribution of the target erosion situation in the above publication is a vertical stripe distribution, for example, as shown in FIG. This has the same problem although the degree is different with respect to the target utilization efficiency described above and the thickness distribution of the thin film formed on the substrate.
[0064]
  (F) In the magnetron sputtering apparatus disclosed in Japanese Patent Laid-Open No. 8-199354 described with reference to FIGS. 21A and 21B, the amplitude and speed change of the reciprocating motion of the magnetic circuit unit 601 are not described. In this publication, in addition to a mechanism for reciprocating a magnetic circuit unit 601 itself in which a plurality of magnetic circuits 601a are integrated, a mechanism for adjusting the interval between the plurality of magnetic circuits 601a, each magnetic circuit 601a and a backing plate ( It has a structure equipped with a mechanism for adjusting the distance to the target surface. Particularly, the latter is configured such that the distance between the magnetic circuit unit 601 and the backing plate (target surface), that is, the degree of inclination can be changed in the long side direction of each magnetic circuit 601a.
[0065]
  However, the magnetron sputtering apparatus in the above publication only shows one specific example of means for adjusting the thickness distribution of the thin film formed on the substrate, and the apparatus configuration becomes complicated and the cost is increased. Since the number of moving parts increases, it becomes difficult to ensure the reliability of the apparatus itself.
[0066]
  In addition, the magnetic circuit unit 601 is used at a position separated from the position closest to the backing plate (target surface) most of the time, and the ability as the magnetic circuit unit 601 cannot be fully exhibited.
[0067]
  (G) In the magnetron sputtering apparatus disclosed in Japanese Patent Application Laid-Open No. 6-192833 described with reference to FIGS. 22A to 22C, the amplitude of the reciprocating motion of the magnetic field generating means 702 is in the short side direction of one magnet unit 703. However, the arrangement pitch of the magnet units 703 is not described in the same manner as in Japanese Patent Application Laid-Open No. 8-134640. Further, the speed of the reciprocating motion of the magnetic field generating means 702 is also sinusoidal in the disclosed example.
[0068]
  Therefore, the erosion of the target 701 does not necessarily proceed uniformly, and there is a difference in the time during which the target is exposed to the high-density plasma by the amount that the reciprocating motion of the magnetic field generating means 702 has a sinusoidal speed change, Target erosion tends to proceed at both ends of the amplitude of the reciprocating motion.
[0069]
  The present invention has been made in view of the above-mentioned problems, and its purpose is to have a simple mechanism composed of cost-effective parts, and to effectively input power to target sputtering. It is an object of the present invention to provide a magnetron sputtering apparatus that can be used and that can maintain a high target utilization efficiency and can keep the thickness distribution of a thin film formed on a substrate within a predetermined range.
[0070]
[Means for Solving the Problems]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatus is disposed opposite to a rectangular substrate on which a thin film is formed in a vacuum chamber, and has a rectangular target larger than the effective film formation area of the substrate, and the target A plasma generating means for generating a plurality of closed racetrack-shaped high-density plasmas on the surface of the target by performing magnetron discharge, and the plasma generating means with respect to the target, the long side of the target Or a driving means for reciprocating in parallel with one of the short sides, the plasma generating means on the surface of the target along the moving direction of the plasma generating means,The distance between the lines parallel to the major axis among the lines connecting the highest plasma density in one closed racetrack high-density plasmaWhen,Among the lines connecting the highest plasma density portions in a plurality of closed racetrack-like high density plasmas, the distance between the lines parallel to the major axis and the distance between the lines due to different high density racetrack-like plasmas adjacent to each otherThe racetrack-shaped high-density plasma is generated so as to be substantially equal to each other.The distance between the lines parallel to the long axis among the lines connecting the highest plasma density in the racetrack high-density plasma.The plasma generating means is reciprocated at a constant speed with the following amplitude.
[0071]
  According to said structure, a plasma production | generation means is along the moving direction of this plasma production | generation means on the surface of the said target,The distance between the lines parallel to the major axis among the lines connecting the highest plasma density in one closed racetrack high-density plasmaWhen,Among the lines connecting the highest plasma density portions in a plurality of closed racetrack-like high density plasmas, the distance between the lines parallel to the major axis and the distance between the lines due to different high density racetrack-like plasmas adjacent to each otherThe racetrack-like high-density plasma is generated so that is substantially equal. As a result, the power supplied for generating the plasma is dispersed into a plurality of plasmas, so that the power density can be suppressed and a large power supply can be performed without abnormal discharge leading to arc discharge. As a result, the film formation rate can be increased.
[0072]
  Furthermore, the drive meansThe distance between the lines parallel to the long axis among the lines connecting the highest plasma density in the racetrack high-density plasma.Since the above plasma generating means is reciprocated at a constant speed with the amplitude of the following magnitude, the target surface portions eroded by the individual racetrack high density plasma will not overlap, and the target is locally It is possible to eliminate the progression of erosion.
[0073]
  Therefore, according to the magnetron sputtering apparatus having the above configuration, it has a simple mechanism composed of cost-effective parts, and can effectively spend the input power for sputtering of the target, and the use of the target. The efficiency can be kept high, and the thickness distribution of the thin film formed on the substrate can be kept within a predetermined range.
[0074]
  Also,According to the above configuration, the interval between the racetrack high-density plasmas is the distance between the highest density portions of the racetrack high-density plasma, so that the composite magnetic circuit is arranged in the direction in which the magnetic units are arranged. The amplitude when reciprocating at a constant speed can be set to be smaller than the distance between the highest density portions of the above-mentioned racetrack-shaped high-density plasma. The target surface portions to be overlapped do not overlap, and the target erosion does not proceed locally.
[0075]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatus is disposed opposite to a rectangular substrate on which a thin film is formed in a first vacuum chamber, and has a rectangular target larger than the effective film formation area of the substrate, A magnetic field generating means disposed on a back surface side of a backing plate for supporting the target and generating a magnetic field on the opposing surface of the substrate of the target; and the magnetic field generating means with respect to the target, the long side of the target Or a driving means for reciprocating in parallel with any one of the short sides, the magnetic field generating means comprising a rectangular magnet unit for generating a magnetic field on the target surface such that the long sides are adjacent to each other, and Composed of a composite magnetic circuit arranged in a plurality so as to show the same polarity, the driving means is the aboveThe pitch P of the lines parallel to the long side of the magnet unit among the lines connecting the points where the component perpendicular to the target surface of the magnetic field generated on the target surface by one magnet unit becomes zeroOn the other hand, the composite magnetic circuit is moved so that the amplitude SW when the composite magnetic circuit is reciprocated at a constant speed in the direction in which the magnetic units are arranged satisfies the relationship SW ≦ P.And each magnet unit in the above-mentioned composite magnetic circuit is arranged on the long side of the magnet unit among the lines connecting the points where the component perpendicular to the target surface of the magnetic field generated on the target surface by each magnet unit becomes zero. It is arranged that the intervals between the parallel lines, which are caused by different magnet units adjacent to each other, are equal to the pitch P.It is a feature.
[0076]
  According to the above configuration, the magnetic field generating means is a composite magnet in which a plurality of rectangular magnet units that generate a magnetic field on the target surface are arranged so that their long sides are adjacent to each other and have the same polarity. By comprising a circuit, a plurality of closed racetrack-like high density plasmas converged by the generated magnetic field can be obtained on the surface of the target that uses these composite magnetic circuits as a source.
[0077]
  As a result, the power supplied for generating the plasma is dispersed into a plurality of plasmas, so that the power density can be suppressed, and high power can be supplied without abnormal discharge leading to arc discharge. The film formation speed as performance can be increased.
[0078]
  Furthermore, the drive meansThe pitch P of the lines parallel to the long side of the magnet unit among the lines connecting the points where the component perpendicular to the target surface of the magnetic field generated on the target surface by one magnet unit becomes zeroOn the other hand, the amplitude SW when the composite magnetic circuit is reciprocated at a constant speed in the direction in which the magnetic units are arranged is set so that the relationship of SW ≦ P is satisfied. The target surface portions eroded by the density plasma are not overlapped, and the target erosion does not proceed locally.
[0079]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, the magnet unit includes a central magnet disposed at the center of the unit, and a peripheral magnet disposed so as to surround the central magnet and so that the magnetic poles having the opposite polarity to the central magnet face each other. The pitch P of the portion parallel to the long side of the magnet unit in the line connecting the points perpendicular to the target surface of the magnetic field generated on the target surface by the central magnet and the peripheral magnet is zero. However, it is formed so that it may become P> MW / 2 with respect to the dimension MW of the short side direction of this magnet unit.
[0080]
  According to the above configuration,the aboveIn addition to the action, the magnet unit is composed of a central magnet arranged at the center of the unit, and a peripheral magnet arranged so as to surround the central magnet and so that the magnetic poles having the opposite polarity to the central magnet face each other. The pitch P of the portion parallel to the long side of the magnet unit among the lines connecting the points perpendicular to the target surface of the magnetic field generated on the target surface by the central magnet and the peripheral magnet is zero. The pitch of the racetrack-shaped high-density plasma formed by a single magnet unit is also MW by forming P> MW / 2 with respect to the dimension MW in the short side direction of the magnet unit. Greater than / 2.
[0081]
  Therefore, the gap between the magnet units is adjusted so that the distance from the racetrack high-density plasma generated in the adjacent magnet units is equal to the pitch interval of the high-density plasma generated in each magnet unit. can do.
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, the composite magnetic circuit includes n (n> 1) magnet units,Each magnet unit
It is characterized in that P = TW / (2 × n + 1) is set when the dimension of the target magnet unit arrangement direction is TW.
[0082]
  According to said structure, in addition to the said effect | action, a composite magnetic circuit consists of n (n> 1) magnet units, and each magnet unit is the above-mentioned of the magnetic field generated on the said target surface by each magnet unit. Of the lines connecting the points where the component perpendicular to the target surface becomes zero, the interval between the lines parallel to the long side of the magnet unit and caused by different magnet units adjacent to each other is equal to the pitch P. And when the dimension of the target in the magnet unit alignment direction is TW, P = TW / (2 × n + 1) is set so that the target has a pitch P interval. Can be eroded.
[0083]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, the magnetic field generating means is arranged in a second vacuum chamber provided on the surface of the target opposite to the surface facing the substrate.
[0084]
  According to the above configuration,the aboveIn addition to the operation, the magnetic field generating means is disposed in the second vacuum chamber provided on the surface opposite to the substrate facing surface of the target, so that the backing plate to which the target is bonded in the apparatus operating state is the target. Both the first vacuum chamber on the side (film formation space side) and the second vacuum chamber on the back side (composite magnetic circuit side) are evacuated.
[0085]
  This eliminates the pressure difference between the two sides of the backing plate to which the target is bonded, which has a substantial mechanical effect, so that the backing plate has the mechanical strength required for bonding to the target and mounting to the device. It can be made thinner than the case where it is strong enough to withstand atmospheric pressure.
[0086]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, the magnetic field generating means disposed in the second vacuum chamber, the driving means for driving the magnetic field generating means, and the second vacuum chamber itself are the same as the target and the backing plate that supports the target. It is characterized by being set to a potential.
[0087]
  According to the above configuration,the aboveIn addition to the action, the magnetic field generating means disposed in the second vacuum chamber, the driving means for driving the magnetic field generating means, and the second vacuum chamber itself have the same potential as the target and the backing plate that supports the target. Therefore, the exhaust of the second vacuum chamber provided on the back side of the target in which the magnetic field generating means is accommodated is about so-called “roughing” such as an oil rotary pump or a combination of an oil rotary pump and a mechanical booster pump. Even when a high voltage is applied to the backing plate to which the target is bonded to cause magnetron discharge for sputtering, the second vacuum chamber provided on the back side of the target in which the backing plate and the magnetic field generating means are accommodated. Or there is no discharge between the contents.
[0088]
  Therefore, the pump for exhausting the second vacuum chamber can be a roughing pump as described above. Therefore, an exhaust system including an expensive pump for high vacuum exhaust and various valves for operating the pump is provided. Since it is not necessary, the cost of the apparatus can be reduced.
[0089]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, in the composite magnetic circuit, both ends of the magnet units on the target substrate facing surface have a strong magnetic field with respect to the center, and both ends in the direction orthogonal to the magnet units are in the center. On the other hand, the magnetic field is adjusted to be weak.
[0090]
  According to the above configuration,the aboveIn addition to the action, the composite magnetic circuit has a strong magnetic field at both ends of the magnet unit on the surface facing the substrate of the target with respect to the center, and both ends in the direction perpendicular to the direction of arrangement of the magnet units with respect to the center. Thus, the target is eroded uniformly and the film thickness distribution on the substrate can be corrected.
[0091]
  Therefore, when the magnet unit is assembled into a composite magnetic circuit, the plasma along the long side of the target is adjusted by adjusting the magnetic field to be stronger with respect to the central part at both ends of the magnet unit on the target surface. The density can be increased, and the film thickness distribution in the direction in which the magnetic field generating means reciprocates (target short side direction) can be corrected.
[0092]
  Furthermore, the density of the high-density plasma at the long-side end (peripheral portion along the short side of the target) of the rectangular magnet unit is reduced by weakening the magnetic field at the end in the direction perpendicular to the magnet unit with respect to the center. Then, when the magnetic field generating means is reciprocated, the target erosion speed based on the difference in plasma residence time on the target surface can be adjusted to correct the film thickness distribution.
[0093]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, the magnet unit includes a magnet assembly in which a central magnet and a peripheral magnet are bonded and fixed to a magnet assembly yoke, and a base yoke that serves as a base of the entire magnet unit. The fastening hole provided in the magnet assembly yoke is fastened to the base yoke with a bolt, and the diameter of the fastening hole is formed to be larger than the diameter of the bolt. Yes.
[0094]
  According to the above configuration,the aboveIn addition to the operation, the magnet unit includes a magnet assembly in which a center magnet and a peripheral magnet are bonded and fixed to a magnet assembly yoke, and a base yoke that serves as a base of the entire magnet unit. Using the fastening holes provided in the magnet assembly yoke, the strength distribution adjustment on the target surface of the magnetic field generated by the magnet unit can be adjusted by bolting the base yoke with the bolt. This can be realized by fastening the bolt with the auxiliary yoke inserted between them.
[0095]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, the fastening hole of the magnet assembly yoke allows the position of the magnet assembly to be adjusted on the base yoke in the driving direction of the magnetic field generating means when the magnet assembly and the base yoke are fastened. It is formed in a long hole.
[0096]
  According to the above configuration,the aboveIn addition to the operation, the fastening hole of the magnet assembly yoke is long so that the position of the magnet assembly can be adjusted on the base yoke in the driving direction of the magnetic field generating means when the magnet assembly and the base yoke are fastened. Fine adjustment so that the pitch in the rectangular short side direction of the portion parallel to the long side direction of the racetrack-shaped high-density plasma is equal when the multiple magnet units are combined. Can do.
[0097]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, at least one of the magnet assembly yoke and the base yoke is characterized in that a longitudinal end portion of the magnet unit is formed thinner than other portions.
[0098]
  According to the above configuration,the aboveIn addition to the action, at least one of the magnet assembly yoke and the base yoke is formed such that the longitudinal end of the magnet unit is thinner than the other portions, so that the magnetic field at the longitudinal end of the magnet unit is smaller than the central portion. Can be adjusted to be particularly weak.
[0099]
  Of the present inventionIn order to solve the above problems, the magnetron sputtering apparatusthe aboveIn addition to the configuration, the magnet assembly yoke and the base yoke are made of a conductive soft magnetic material, and the central magnet and the peripheral magnet are a conductive magnet material or a magnet material whose surface is coated with a conductive material. The magnet assembly is characterized in that the central magnet and the peripheral magnet are fixed to the magnet assembly yoke with a conductive adhesive.
[0100]
  According to the above configuration,the aboveIn addition to the operation, the magnet assembly yoke and the base yoke are made of a conductive soft magnetic material, and the central magnet and the peripheral magnet are made of a conductive magnet material or a magnet material whose surface is coated with a conductive material. The magnet assembly is configured such that the central magnet and the peripheral magnet are fixed to the magnet assembly yoke with a conductive adhesive, so that the magnetic field generating means is supported by a conductive material and necessary electrical connection is made. The same potential can be obtained up to the magnet surface of the composite magnetic circuit.
[0101]
DETAILED DESCRIPTION OF THE INVENTION
  An embodiment of the present invention will be described below with reference to FIGS.
[0102]
  As shown in FIG. 1, the magnetron sputtering apparatus according to the present embodiment includes a film forming chamber 1 constituting a first vacuum chamber, and a magnet chamber 2 constituting a second vacuum chamber adjacent to the film forming chamber 1. It has.
[0103]
  In the film forming chamber 1, a substrate 3 on which a thin film is formed and a target 4 which is opposed to the substrate 3 and serves as a base material for the thin film formed on the surface of the substrate 3 are arranged. .
[0104]
  The substrate 3 is mounted on a substrate holder 5 provided in the film forming chamber 1 on the surface opposite to the film forming surface. The mounting of the substrate 3 on the substrate holder 5 is appropriately performed when it is performed in the film forming chamber 1, in a previous vacuum chamber (not shown), or in the atmosphere. Shall be selected.
[0105]
  The target 4 is disposed at the boundary between the film formation chamber 1 and the magnet chamber 2 and constitutes the bottom surface of the film formation chamber 1. The target 4 is connected to a backing plate 6 constituting the upper surface of the magnet chamber 2 on the side opposite to the surface facing the substrate 3 by a low melting point metal (not shown) such as solder or indium.
[0106]
  The backing plate 6 has a mechanism that is cooled by cooling water or the like, and suppresses the temperature rise of the connected target 4 during sputtering.
[0107]
  In the magnet chamber 2, a magnetic field generating mechanism 7 is disposed as a magnetic field generating means for generating a tunnel-shaped poloidal magnetic field on the surface of the target 4 connected to the backing plate 6. The detailed configuration of the magnetic field generation mechanism 7 will be described later.
[0108]
  Further, in the magnet chamber 2, a drive device 8 is provided for reciprocating the magnetic field generating mechanism 7 in the directions of arrows A and B at a constant speed.
[0109]
  Since the film forming chamber 1 constitutes the first vacuum chamber as described above, the film forming chamber 1 is placed outside the film forming chamber 1 (in the direction of the arrow in the figure) through the exhaust duct 9 by an exhaust pump (not shown). And a mechanism for introducing gas into the film formation chamber 1 through a gas pipe 10 from a gas supply source (not shown) outside the film formation chamber 1. By these mechanisms, the pressure in the film formation chamber 1 is set to about 0.01 to 1 Pa during film formation.
[0110]
  The magnet chamber 2 is provided with a mechanism for exhausting gas to the outside of the magnet chamber 2 (arrow in the figure) through an exhaust duct 11 by an exhaust pump (not shown). By this mechanism, the inside of the magnet chamber 2 is continuously exhausted during film formation, and the pressure is set to about 0.01 to 1 Pa.
[0111]
  Since the film forming chamber 1 and the magnet chamber 2 may be set to a pressure of about 0.01 to 1 Pa as described above, a mechanical booster pump is used as an exhaust pump.
[0112]
  For example, the pressure in the film forming chamber 1 is set to a pressure of about 0.05 to 1 Pa at the time of film formation (at the time of gas introduction).^-Five-10^-FourThe pressure is set to about Pa.
[0113]
  The magnet chamber 2 has an atmospheric pressure of 10^FiveSince it is about Pa, there is no problem with a pressure of about 100 Pa in order to prevent warping of the target 4.
[0114]
  In the magnetron sputtering apparatus configured as described above, the magnet chamber 2, the driving device 8, the magnetic field generating mechanism 7, and the backing plate 6 are connected so as to be electrically at the same potential, while the film forming chamber 1 is Since the magnet chamber 2 is grounded, the magnet chamber 2 is fixed to the film forming chamber 1 via insulating materials 12 and 12 so as not to be electrically short-circuited.
[0115]
  Further, the above-described exhaust duct 11 is connected to the magnet chamber 2 via an insulating flange 13.
[0116]
  Further, on both sides of the film forming chamber 1, valves 14 and 14 for connecting to other mechanisms (not shown) adjacent to the film forming chamber 1 are provided. Here, the other mechanism is, for example, another film forming chamber, a load lock chamber, or a mechanism in the atmosphere. Therefore, between the film forming chamber 1 and another mechanism connected to the film forming chamber 1 by the valve 14, it is possible to make the same atmosphere or different atmospheres by opening and closing the valve 14.
[0117]
  Further, a mask 15 for preventing the sputtered thin film from adhering during sputtering is provided on the peripheral edge of the substrate 3.
[0118]
  Further, a ground shield 16 is provided at the peripheral edge of the target 4 to prevent the mechanism around the target 4 from being exposed to plasma during sputtering.
[0119]
  The backing plate 6 is connected to a power source 17 for applying a negative potential.
[0120]
  Therefore, the magnetic field generation mechanism 7, the backing plate 6, and the power source 17 constitute plasma generation means for generating high-density plasma on the surface of the target 4.
[0121]
  Here, the magnetic field generating mechanism 7 provided in the magnetron sputtering apparatus will be described in detail.
[0122]
  First, the configuration of the magnetic field generation mechanism 7 will be briefly described.
[0123]
  As shown in FIG. 1, the magnetic field generation mechanism 7 has a composite magnetic circuit structure in which a plurality of magnet units 30 are arranged on a substantially flat support member 7 a parallel to the target 4. . The support member 7a is fixed to the driving device 8, and is moved in the directions of arrows A and B by the driving device 8. The magnet unit 30 is used as a magnetron cathode electrode in the magnetron sputtering apparatus.
[0124]
  That is, the magnetic field generation mechanism 7 has a function as a plasma converging means for converging plasma on the surface of the target 4 during film formation.
[0125]
  Each of the magnet units 30 has a rectangular shape in which the direction perpendicular to the moving direction of the magnetic field generating mechanism 7 is the longitudinal direction, and each magnet unit 30 is disposed on the support member 7a at substantially equal intervals.
[0126]
  Next, magnetron discharge using the magnet unit 30 will be described below with reference to FIGS. 2A to 2D show only necessary members for convenience of explanation.
[0127]
  The magnet unit 30 has a rectangular shape, and as shown in FIG. 2A, a center magnet 31, a peripheral magnet 32 formed in a substantially mouth shape around the center magnet 31, and the center magnet 31. It comprises a yoke 33 for fixing the peripheral magnet 32. The central magnet 31 and the peripheral magnet 32 are fixed with a magnetic pole having a reverse polarity facing the yoke 33. Here, the central magnet 31 is in contact with the yoke 33 and the peripheral magnet 32 is in contact with the yoke 33.
[0128]
  In the magnet unit 30, the center magnet 31, the peripheral magnet 32, and the yoke 33 constitute a magnetic circuit, and a poloidal magnetic field is generated in the space above the magnet unit 30. That is, in the magnet unit 30, as shown in FIG. 2B, the magnetic field lines 34 generate a poloidal magnetic field from the peripheral magnet 32 toward the central magnet 31.
[0129]
  The shape and strength of the magnetic force lines 34 in the magnet unit 30 are determined by the dimensions and magnetic characteristics of the center magnet 31, the peripheral magnet 32, and the yoke 33. The yoke 33 is dimensioned so as not to be magnetically saturated.
[0130]
  In the magnetron sputtering apparatus configured as described above, the target 4 bonded to the backing plate 6 is disposed on the side of the magnetic pole surface opposite to the yoke 33 of the magnet unit 30 as shown in FIG. Here, if the backing plate 6 is made of a non-ferromagnetic material such as copper, and the target 4 is made of a non-ferromagnetic material, the magnet unit 30 maintains the shape of the generated magnetic force lines 34. A magnetic field is generated on the surface of the target 4.
[0131]
  Moreover, as shown in FIG.2 (d), the magnet unit 30 forms the magnetic force line 34 not only in a longitudinal direction but in a transversal direction on the surface of the target 4. FIG. And the magnetic field distribution by the magnetic force line 34 at this time is called "tunnel-shaped magnetic field" or "tunnel-shaped poloidal magnetic field" from the shape. That is, the magnet unit 30 generates a tunnel-like magnetic field on the surface of the target 4.
[0132]
  Here, the sputtering in the magnetron sputtering apparatus will be described below. Here, a case where the target 4 is not a ferromagnetic material will be described.
[0133]
  First, as shown in FIG. 2D, in a state where a tunnel-like magnetic field is formed on the surface of the target 4, the surface side of the target 4 is evacuated and an inert gas such as Ar is introduced.^-2-10^-1Hold at a pressure of about Pa.
[0134]
  Next, as shown in FIG. 2C, a negative voltage is applied from the power source 17 to the backing plate 6 to which the target 4 is bonded, and an electric field 35 directed to the surface of the target 4 is applied to cause glow discharge.
[0135]
  At this time, the surface of the target 4 is bombarded with ions in the plasma, and secondary electrons emitted by the γ action of the bombardment of the ions are supplemented by a tunnel-like magnetic field. On the surface of the target 4, an elongated annular (hereinafter referred to as a racetrack) high-density plasma 36 is formed along a tunnel-like magnetic field.
[0136]
  Subsequently, ions in the plasma are accelerated toward the target 4 by the electric field of the ion sheath generated in the vicinity of the surface of the target 4 and collide with the target 4 to scatter substances constituting the target 4. At the same time, secondary electrons are also emitted from the target surface by the γ action. The particles scattered from the surface of the target 4 adhere to and deposit on the substrate 3 facing the target 4 to form a thin film.
[0137]
  The racetrack-shaped high-density plasma 36 has the highest density at a position where the magnetic field is parallel to the surface of the target 4, that is, a position where the magnetic field component perpendicular to the target 4 is zero. At this position, erosion due to the sputtering action of the target 4 proceeds most rapidly. Therefore, on the target 4, as shown in FIG. 2D, a racetrack-shaped erosion region 37 having a shape along the high-density plasma 36 is generated.
[0138]
  In the magnet unit 30 used in the magnetron sputtering apparatus of the present invention, the interval in the short direction of the magnet unit 30 in the racetrack-like erosion region 37 is ½ or more of the dimension MW in the short side direction of the magnet unit 30. The dimensions of the center magnet 31 and the peripheral magnet 32 are determined.
[0139]
  As described in the related art, if the sputtering is continued while the single rectangular magnet unit 30 is stationary with respect to the target 4, the target 4 is locally consumed. In-plane distribution of the thickness and film characteristics of the thin film is generated. Therefore, it is necessary to make the thickness of the thin film formed on the substrate 3 uniform or to use the target 4 effectively by consuming the target 4 uniformly.
[0140]
  As shown in FIGS. 3A and 3B, the magnetic field generation mechanism 7 generates a plurality of racetrack-shaped high-density plasmas 36 on the surface of the target 4. Here, since the magnetic field generation mechanism 7 includes seven magnet units 30, seven high-density plasmas 36 are formed on the surface of the target 4.
[0141]
  Each magnet unit 30 has dimensions of the center magnet 31 and the peripheral magnet 32 so that the distance between the racetrack-like erosion areas 37 is 1/2 or more of the dimension MW in the short direction of the magnet unit 30 as described above. Therefore, the clearance C is maintained between the magnet units 30 and the magnet units 30 are arranged in such a manner that the long sides are adjacent to each other, and each of the adjacent magnet units 30 forms a racetrack-like high-density plasma. The distance between the portion where the erosion of the target 4 progresses most, that is, the portion with the highest plasma density, can be made equal to the distance in the short direction of the magnet unit 30 in the erosion region 37. In the following description, the interval in the short direction of the magnet unit 30 in the erosion area 37 is defined as a pitch P.
[0142]
  In the state shown in FIG. 3 (a), if the magnetic field generating mechanism 7 is stopped and the magnetron discharge is continued, the target 4 becomes a racetrack-shaped erosion region 37 formed by the high-density plasma 36 (FIG. 2 (d)). Are eroded into a state in which a plurality of are arranged at an equal pitch P.
[0143]
  However, the magnetron sputtering apparatus configured as described above is provided with a driving device 8 that reciprocates the magnetic field generating mechanism 7 in the short direction of the magnet unit 30 in a plane parallel to the target 4. Therefore, the magnetic field generating mechanism 7 is reciprocated at a constant speed by the driving device 8, and the amplitude SW is set equal to or smaller than the pitch P of the high-density plasma 36. As a result, the time of exposure to the racetrack-shaped high-density plasma 36 on the entire surface of the target 4 is averaged, so that the progress of erosion on the entire surface of the target 4 can be made uniform.
[0144]
  At this time, the dimension TW (short-side dimension) of the target 4 in the direction in which the magnetic field generating mechanism 7 reciprocates is multiplied by the pitch P by at least twice the number n of magnet units 30 (n = 7 in the present embodiment). Must be greater than Actually, the portion where the erosion of the target 4 progresses has a finite width, but even if the magnet unit 30 is kept stationary and the magnetron discharge is continued, it does not seem to extend outside the width of the magnet unit 30 itself. The dimensions of the center magnet 31 and the peripheral magnet 32 of the magnet unit 30 are determined.
[0145]
  In the magnet unit 30 of the present invention, the dimensions of the center magnet 31 and the peripheral magnet 32 are determined so that the pitch P is equal to or greater than 1/2 of the dimension MW in the short side of the magnet unit 30. Therefore, TW = P (2n + 1 If the dimension TW of the target 4 is determined so as to be, the target 4 can be used effectively without enlarging the portion that is not eroded at the end in the reciprocating direction.
[0146]
  Further, details of the configuration of the magnetic field generation mechanism 7 will be described below with reference to FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b).
[0147]
  4A is a plan view of the magnetic field generation mechanism 7, and FIG. 4B is a side view of the magnetic field generation mechanism 7 of FIG. 5A is an enlarged view of the main part 40 of FIG. 4A, and FIG. 5B is a side view of FIG. 5A.
[0148]
  The magnetic field generation mechanism 7 has a configuration in which seven magnet units 30 are arranged as shown in FIG. As shown in FIG. 4B, each of the magnet units 30 has a height from the support member 7a of the center magnet 31 and the peripheral magnet 32 on the end portion in the longitudinal direction of the magnet unit 30, and the other center magnet 31. And it is formed to be smaller than the peripheral magnet 32.
[0149]
  The center magnet 31 and the peripheral magnet 32 are divided into a plurality of blocks. For example, in the central magnet 31, only one block at the longitudinal end of the magnet unit 30 is defined as the central magnet 31b, and the other blocks are distinguished from the central magnet 31a for convenience. On the other hand, the peripheral magnet 32 is one block of the long side portion at the longitudinal end of the magnet unit 30.
For convenience, the peripheral magnet 32b and the short side block are distinguished from the peripheral magnet 32c.
[0150]
  Therefore, in the magnet unit 30, the thickness of the portion constituted by the central magnet 31a, the peripheral magnet 32b, and the peripheral magnet 32c on the longitudinal end portion side is the thickness of the portion constituted by the central magnet 31b and the peripheral magnet 32a. It is formed to be thinner. This detailed configuration will be described later.
[0151]
  Furthermore, the yoke 33 to which the central magnet 31 and the peripheral magnet 32 are attached includes, as shown in FIG. 5B, a base yoke 41, a central magnet magnet assembly yoke 42 for attaching the central magnet 31, The magnet assembly yoke 43 is a peripheral magnet for attaching the magnet 32.
[0152]
  The central magnet 31 is bonded and fixed to a central magnet magnet assembly yoke 42 to form a central magnet magnet assembly 44, and the peripheral magnet 32 is bonded and fixed to a peripheral magnet magnet assembly yoke 43 to form a peripheral magnet magnet assembly 45. doing.
[0153]
  The peripheral magnet magnet assembly 45 is formed with a fastening hole 47 for fastening the base yoke 41 with a bolt 46. That is, the peripheral magnet magnet assembly 45 is fastened and fixed to the base yoke 41 by the bolts 46. Although not shown in the drawing, the magnet assembly 44 for the central magnet is similarly fastened and fixed by bolts from the back side of the base yoke 41.
[0154]
  The fastening hole 47 of the magnet assembly 45 for the peripheral magnet is larger than the diameter of the bolt 46, and the fixing position is finely adjusted when the bolt 46 is used to fix the magnet assembly 45 for the peripheral magnet to the base yoke 41. It is formed in a long hole shape so that it can be made. That is, when the plurality of magnet units 30 are combined, fine adjustment is made so that the pitch P in the rectangular transverse direction of the portion parallel to the longitudinal direction of the magnet unit 30 of the racetrack-like high-density plasma 36 is equal. Can do.
[0155]
  Further, the central magnet 31 and the peripheral magnet 32 are made of a conductive magnet material or have a conductive surface coating (not shown), and the magnet assembly 44 for the central magnet, which is a constituent member of the magnet unit 30, and the periphery In the magnet assembly 45 for the magnet, the central magnet 31 and the peripheral magnet 32 are fixed to the central magnet assembly yoke 42 and the peripheral assembly magnet assembly yoke 43 by a conductive adhesive (not shown). Thus, the surfaces of the center magnet 31 and the peripheral magnet 32 can be electrically set to the same potential as the magnet assembly 44 for the central magnet and the magnet assembly 45 for the peripheral magnet, so that the backing plate to which the target 4 is bonded up to the magnet unit 30 can be obtained. 6 and the same potential.
[0156]
  Furthermore, the base yoke 41, the magnet assembly 44 for the central magnet, and the magnet assembly 45 for the peripheral magnet are formed so that one or both of them are thinner than the other portions at the longitudinal end of the magnet unit 30. . Thereby, it can adjust so that the magnetic field in the longitudinal direction edge part of the magnet unit 30 may become weak with respect to a center part.
[0157]
  Here, the structure for making the magnetic field intensity different in the longitudinal direction edge part and the center part of the said magnet unit 30 is demonstrated below, referring FIG. 6 (a)-(d). FIGS. 6B to 6D are longitudinal sectional views of various configurations of the magnet unit 30 used for the magnetron cathode electrode of the magnetron sputtering apparatus of the present invention. FIG. 6A is a plan view of the magnet unit 30.
[0158]
  In the magnet unit 30, as described above, the central magnet magnet assembly 44 and the peripheral magnet magnet assembly 45 are fastened with bolts to the base yoke 41 serving as the entire base of the magnet unit 30. The base yoke 41, the central magnet magnet assembly 44, and the peripheral magnet magnet assembly 45, which are constituent members, are formed at the end 30b in the longitudinal direction of the magnet unit 30, and either one or both are formed thinner than the central portion 30a.
[0159]
  In order to adjust the intensity distribution of the magnetic field generated by the magnet unit 30 on the surface of the target 4, the distance between the surface of the magnet unit 30 and the surface of the target 4 is determined by the distance between the magnetic field generation mechanism 7 and the backing plate 6. It comes to adjust.
[0160]
  In the magnet unit 30 shown in FIG. 6B, the thickness of the magnet assembly 44 for the central magnet and the magnet assembly 45 for the peripheral magnet are made uniform, and the thickness of the base yoke 41 is set at the central portion at the longitudinal end 30b of the magnet unit 30. It is formed to be thinner than 30a. Thereby, between the magnet unit 30 surface and the target 4 surface, the distance in the longitudinal direction end part 30b of the magnet unit 30 becomes longer than the distance in the center part 30a, and the magnetic field intensity in the surface of the target 4 is this magnet unit 30. The region corresponding to the longitudinal direction end portion 30b is smaller than the region corresponding to the central portion 30a. That is, the magnet unit 30 is configured to weaken the magnetic field strength at the longitudinal end portion 30b of the magnet unit 30.
[0161]
  Further, in the magnet unit 30 shown in FIG. 6C, the thicknesses of the magnet assembly 44 for the central magnet and the magnet assembly 45 for the peripheral magnet are uniform, similarly to the magnet unit 30 shown in FIG. In the magnet unit 30, an auxiliary yoke 48 is provided between the base yoke 41 and the peripheral magnet magnet assembly 45 at a portion other than the central portion of the central portion 30 a. Although not shown, an auxiliary yoke 48 having the same thickness is provided between the central magnet magnet assembly 44 and the base yoke 41. Thereby, the surface of the region other than the vicinity of the center of the central portion 30a of the magnet unit 30 comes closer to the target 4, and as a result, the magnetic field strength in the vicinity of the center of the target 4 becomes weaker than the both side portions.
[0162]
  Furthermore, the magnet unit 30 shown in FIG. 6D is provided with the auxiliary yoke 48 only in the vicinity of the center of the central portion 30a of the magnet unit 30 shown in FIG. 6B. As a result, only the surface near the center of the magnet unit 30 approaches the target 4, and as a result, the magnetic field strength near the center of the target 4 becomes stronger than other regions.
[0163]
  In the magnetic field generating mechanism 7, all the magnet units 30 to be combined may have the same size and the same polarity magnetic pole configuration. However, in general, when a plurality of identical magnet units 30 are arranged, the magnetic field generating mechanism 7. Since the magnetic field intensity on the surface of the target 4 generated more weakens at the end of the magnet unit 30 in the arrangement direction, for example, the magnet units 30 at both ends have the dimension in the arrangement direction of the magnet unit 30 of the center magnet 31 and the peripheral magnet 32. It can also be increased to obtain magnetic field uniformity.
[0164]
  For example, as shown in FIG. 7, when the magnet unit 30 is combined in the magnetic field generation mechanism 7, the auxiliary plate is interposed between the support member 7 a of the magnetic field generation mechanism 7 and the magnet unit 30 at the end in the short direction. If 49 is provided, the magnetic field strength of the magnetic field generated on the target 4 by the magnetic field generation mechanism 7 can be increased at the end of the magnet unit 30 in the arrangement direction. As a result, the magnetic field strength on the surface of the target 4 is uniform. Will be achieved. The auxiliary plate 49 may not have soft magnetism as long as it is a conductive material.
[0165]
  Here, the actual dimensions of the magnetic field generation mechanism 7 shown in FIGS. 4 (a) and 4 (b) will be described.
[0166]
  The target 4 applied to the magnetic field generation mechanism 7 has a size of 825 mm × 975 mm × 6 mm, and the thickness of the backing plate 6 is 19 mm. Since there are seven magnet units 30 (n = 7), the width TW = 825 mm in the arrangement direction of the magnet units 30 of the magnetic field generation mechanism 7, and TW = (2 × 7 + 1) × P, and the pitch P = 55 mm. Each magnet unit 30 was arranged so as to be.
[0167]
  Further, the central magnet 31 and the peripheral magnet 32 constituting the magnet unit 30 are neodymium rare earth permanent magnets having a thickness (magnetization direction) of 15 mm, and have a residual magnetic flux density of about 1.35T. The central magnet 31 and the peripheral magnet 32 belonging to the magnet units 30 at both ends are designed so as to increase the arrangement direction dimension of the magnet unit 30 more than the central magnet 31 and the peripheral magnet 32 belonging to the other magnet unit 30.
[0168]
  Thereby, the arrangement direction magnetic field strength distribution of the magnet units 30 can be made uniform in a state where the seven magnet units are on the same plane. Further, the magnet assembly 44 for the center magnet, the magnet assembly 45 for the peripheral magnet, and the base yoke 41 are thinly formed at the end in the long side direction of each magnet unit 30.
[0169]
  As described above, in order to make the erosion of the target 4 substantially uniform, the pitch P of the high-density plasma 36 on the surface of the target 4 needs to be the same in the magnetic field generation mechanism 7 as described above.
[0170]
  In order to make the pitch P between the magnet units 30 the same in the magnetic field generation mechanism 7, the width MW and the pitch P in the short direction of the magnet unit 30 have a relationship of P> MW / 2 as described above. I just need it. This will be described below with reference to FIGS. 8A to 8C and FIGS. 9A to 9C. 8A to 8C are explanatory diagrams for the case of P> MW / 2, and FIGS. 9A to 9C are explanatory diagrams for the case of P <MW / 2.
[0171]
  As shown in FIG. 8 (a), the magnet unit 30 has a line of magnetic force 34 in the arrangement of the target 4 shown in FIG. 8 (b) rather than 1/2 of the length MW in the short direction of the magnet unit 30. When the pitch P that is the distance between the positions parallel to the surface of the target 4 is set large, as shown in FIG. 8B, the highest plasma portion of the high-density plasma 36 formed on the surface of the target 4 The distance between them is also the pitch P.
[0172]
  Therefore, when the magnet units 30 set to P> MW / 2 are arranged in the longitudinal direction, a gap C can be provided between the magnet units 30 as shown in FIG. In this case, by adjusting the gap C, the distance between the high-density plasmas 36 between the adjacent magnet units 30 can be made the same as the pitch P of the magnet units 30. That is, the intervals between the high-density plasmas 36 when the magnet units 30 are arranged in the short direction of the magnet units 30 can be made the same.
[0173]
  On the other hand, as shown in FIG. 9A, the magnet unit 30 ′ has a target shown in FIG. 9B that is less than ½ of the length MW in the short direction of the magnet unit 30 ′. 4, when the distance P ′ between positions where the magnetic lines of force 34 ′ are parallel to the surface of the target 4 is set small, as shown in FIG. 9B, the high-density plasma 36 formed on the surface of the target 4. The distance between the highest parts of 'is also P'. Here, if MW is constant, a relationship of P> P ′ is established. The magnet unit 30 'includes a center magnet 31', a peripheral magnet 32 ', and a yoke 33'.
[0174]
  Therefore, even if the magnet units 30 ′ set to P ′ <MW / 2 are arranged in the longitudinal direction in an attempt to make the distance between the high-density plasmas 36 ′ of the magnet units 30 ′ the same, FIG. ), Since P ′ <MW / 2, the distance P ″ of the high-density plasma 36 ′ between the magnet units 30 ′ is equal to the distance P even if the magnet units 30 ′ are arranged without gaps. The distance between the high-density plasmas 36 ′ cannot be the same when the magnet units 30 ′ are arranged in the short direction of the magnet units 30 ′.
[0175]
  From the above, it can be seen that in order to make the erosion of the target 4 uniform, it is sufficient that the width MW and the pitch P in the short direction of the magnet unit 30 have a relationship of P> MW / 2.
[0176]
  Therefore, as shown in FIG. 10, among the dimensions of the target 4, the dimension TW in the direction in which the plurality of magnet units 30 are arranged is parallel to the longitudinal direction of the magnet unit 30 of the racetrack-shaped high-density plasma 36. It can be designed such that the pitch P in the rectangular transverse direction of the portion satisfies the relationship of P = TW / (2 × n + 1). In this state, when sputtering is performed without the magnetic field generation mechanism 7 moving, the target 4 is eroded at the portions arranged at the pitch P as shown in FIG.
[0177]
  The magnetic field generation mechanism 7 is configured to reciprocate at a constant speed in the direction in which the magnet units 30 are arranged. The amplitude SW of the magnetic field generating mechanism 7 at this time is eroded by the individual high-density plasmas 36 by having a relationship of SW ≦ P with respect to the long side portion arrangement pitch P of the racetrack-like high-density plasmas 36. The surface of the target 4 is set so as not to overlap. In this case, as shown in FIG. 11B, the target 4 is eroded substantially uniformly without locally eroding the target 4.
[0178]
  As described above, the present invention is not intended to make the progress of the erosion progress of the target 4 completely uniform, but to keep the film thickness distribution of the thin film formed on the substrate 3 within a predetermined range. The purpose is to maximize the use efficiency of the.
[0179]
  For example, if the target 4 is infinitely large, a thin film having a uniform thickness can be formed on the substrate 3 if the erosion proceeds completely uniformly. In this case, the ratio between the target material deposited on the substrate 3 as a thin film and the target material removed from the surface of the target 4 is zero. This is because the target 4 has an infinite size, and therefore the denominator indicating the ratio is infinite.
[0180]
  Further, if the area of the target 4 and the substrate 3 is the same or small, the thickness of the thin film formed on the substrate 3 is not uniform even if the target 4 is uniformly eroded.
[0181]
  Therefore, it is conceivable to use a target 4 that is slightly larger than the effective film formation area of the substrate 3. In this case, the target 4 has a side length ratio of 1.2 to 1.5 times, preferably 1.3 to 1.4 times that of the substrate 3.
[0182]
  In this case, the magnetic field generation mechanism 7 is arranged so that the erosion progress of the target 4 is made as uniform as possible, and the erosion progress is made faster at the periphery of the target 4 than the central portion in order to make the thin film formed on the substrate 3 uniform. Adjusted.
[0183]
  Therefore, as shown in FIG. 11C, it can be seen that the erosion progress of both ends of the target 4 is progressing more than the erosion progress of the other portions.
[0184]
  Then, if the magnetic field generating mechanism 7 is reciprocated in the direction in which the magnet units 30 are arranged with the amplitude SW ≦ P, the target 4 as a whole is slightly eroded at the periphery as shown in FIG. As can be seen, it is almost uniformly eroded.
[0185]
  Thus, since the size of the target 4 is finite, the ratio between the target material deposited on the substrate 3 as a thin film and the target material removed from the surface of the target 4 is not zero. About 50% of the amount of the target material removed from the surface of the target 4 is deposited on the substrate 3.
[0186]
  Furthermore, since the ratio of the volume of the eroded part of the target 4 to the volume of the new target base material is 20 to 30%, about 60% at most, the target material actually deposited on the surface of the substrate 3 is a new target. Most of 4 itself is only about 30%.
[0187]
  Thus, by weighting the progress of erosion of the target 4, the film thickness distribution of the thin film formed on the substrate 3 can be adjusted, and the usage efficiency of the target 4 itself can be increased.
[0188]
  Specifically, for example, when the magnet unit 30 is incorporated in the magnetic field generation mechanism 7, the magnetic field is strong against the center at both ends in the arrangement direction of the magnet units 30 on the surface of the target 4, and the end portions in the direction perpendicular to the arrangement of the magnet units 30. Thus, the dimensions of the central magnet 31, the peripheral magnet 32, and the yoke 33 are adjusted so that the magnetic field becomes weaker with respect to the central portion. As a result, the target 4 can be uniformly eroded, and the film thickness distribution of the thin film on the substrate 3 can be corrected.
[0189]
  For example, the three-dimensional graphs shown in FIGS. 12 and 13 assume that the surface of the target 4 is uniformly eroded, and the emission density of sputtered particles is proportional to the cosine of the angle formed with respect to the normal direction of the surface of the target 4. In this case, the result of the simulation of the film thickness distribution of the thin film formed on the surface of the substrate 3 based on the cosine law is shown.
[0190]
  In the above three-dimensional graph, the target 4 has a similar shape of 1.5 times the length of the side with respect to the substrate 3, and the substrate 3 shows the result when the short side is 550 mm and the long side is 650 mm. Yes.
[0191]
  Here, the numerical values on the horizontal axis of the three-dimensional graphs in FIGS. 12 and 13 indicate the distances from the centers of the respective sides of the substrate 3. That is, numerical values from −270 mm to +270 mm are described on the axis corresponding to the short side direction of the substrate 3, and −320 mm to +310 mm are described on the axis corresponding to the long side direction. The vertical axis represents the relative film thickness distribution of the thin film formed on the surface of the substrate 3. The numerical value on the vertical axis indicates the film thickness deviation in the same plane of the substrate 3 with (Tmax + Tmin) / 2 as the central film thickness (distribution 0). Moreover, if the value Z of the said vertical axis | shaft is shown with numerical formula, it will become as follows.
[0192]
  Z = {Tlocal− (Tmax + Tmin) / 2} / {(Tmax + Tmin) / 2} × 100
  Here, Tmax is the in-plane maximum film thickness, Tmin is the in-plane minimum film thickness, and Tlocal is the film thickness at each position.
[0193]
  Usually, the film thickness distribution is evaluated by a numerical value representing ± (Tmax−Tmin) / (Tmax + Tmin) as a percentage. In the above formula, this corresponds to a value obtained by substituting Tmax or Tmin into Tlocal.
[0194]
  Although the degree of film thickness distribution of the thin film formed on the surface of the substrate 3 depends on the distance between the substrate 3 and the target 4, as described above, the target 4 is not infinitely larger than the substrate 3. Reflecting this, as shown in the three-dimensional graph shown in FIG. 12, the film thickness is reduced at the peripheral edge of the substrate 3, particularly at the four corners.
[0195]
  In order to correct this, a film thickness distribution simulation based on the cosine law is performed on the periphery of the target 4 so that the erosion progress is fast (the emission density of sputtered particles is large), resulting in a three-dimensional graph shown in FIG. . It can be seen from this three-dimensional graph that the drop in film thickness at the peripheral edge of the substrate 3 is corrected.
[0196]
  Therefore, when the magnet unit 30 is incorporated in the magnetic field generation mechanism 7, the magnetic field is stronger along the long side of the target 4 by making the magnetic field stronger than the center at both ends of the magnet unit 30 in the arrangement direction on the surface of the target 4. The plasma density in the portion can be increased, and the film thickness distribution in the direction in which the magnetic field generation mechanism 7 reciprocates (the short side direction of the target 4) can be corrected.
[0197]
  Further, by weakening the magnetic field with respect to the central portion at the end portion in the direction perpendicular to the arrangement of the magnet units 30, the height at the end portion in the long side direction (peripheral portion along the short side of the target 4) of the rectangular magnet unit 30 is increased. When the density of the density plasma is reduced and the magnetic field generation mechanism 7 reciprocates, the erosion progress speed of the target 4 based on the difference in the plasma residence time on the surface of the target 4 can be adjusted, and the film thickness distribution can be corrected. .
[0198]
  As described above, with the configuration disclosed in the present invention, a magnetron capable of forming a thin film with a uniform thickness and film quality on the surface of a stationary rectangular substrate using a rectangular target larger than the effective film forming area of the substrate. A magnetron sputtering apparatus provided with a cathode electrode can be configured in a form capable of high-speed film formation without providing a complicated mechanism.
[0199]
  Specifically, since the magnetic field generating means is a combination of a plurality of rectangular magnet units, a plurality of racetrack-shaped high-density plasma can be obtained. As a result, the power supplied for plasma generation is dispersed into a plurality of plasmas, so that it is easier to suppress the power density than when a single magnet unit is used, and there is no abnormal discharge leading to arc discharge. Large power can be supplied, and the deposition rate as the performance of the apparatus can be increased.
[0200]
  With respect to a single magnet unit, the pitch P of the portion parallel to the long side direction of the magnet unit of the racetrack-shaped high-density plasma formed on the target surface thereby is set to > MW / 2 so that the pitch of the racetrack high density plasma formed by the adjacent magnet units is equal to the pitch P of the racetrack high density plasma formed by the individual magnet units. The clearance C between the magnet units can be secured and arranged.
[0201]
  On the other hand, since the magnetic field generating means is installed in a vacuum chamber provided on the back side of the target, the backing plate to which the target is bonded is the target side (film formation space side) and the back side (composite magnetic circuit side). Both sides are evacuated. This eliminates the pressure difference between the two sides of the backing plate to which the target is bonded, which has a substantial mechanical effect, so that the backing plate has the mechanical strength required for bonding to the target and mounting to the device. It can be made thinner than the case where it is strong enough to withstand atmospheric pressure.
[0202]
  In addition, since the distance between the surface of the magnetic field generating means and the target surface can be reduced, when the same magnetic field generating means is used, the magnetic field intensity at the target surface can be increased, so that higher density plasma is generated. And the device performance can be improved. Further, the volume of the permanent magnet necessary for obtaining a constant magnetic field strength can be reduced, which is advantageous in terms of cost.
[0203]
  Further, since the magnetic field generating means, the main part of the reciprocating drive system of the magnetic field generating means, and the vacuum chamber itself are at the same potential as the target and the backing plate, the exhaust of the vacuum chamber provided on the back surface of the target in which the magnetic field generating means is accommodated Even at the so-called “roughing” level, such as an oil rotary pump or a combination of an oil rotary pump and a mechanical booster pump, a high voltage is applied to the backing plate to which the target is bonded to cause magnetron discharge for sputtering. In this case, there is no discharge between the backing plate and the vacuum chamber provided on the rear surface of the target in which the magnetic field generating means is stored or the contents thereof.
[0204]
  Moreover, the pump for exhausting the vacuum chamber provided on the back side of the target where the magnetic field generating means is housed can also be a rough pump as described above, and an expensive pump for high vacuum exhaust and operation of it. Since an exhaust system including various valves is not required, the cost of the apparatus can be reduced.
[0205]
  Furthermore, when the magnet unit is assembled into a composite magnetic circuit, the magnetic field is strong against the center at both ends of the target surface in the magnet unit arrangement direction, and the magnetic field is weak against the center at the end of the magnet unit arrangement at right angles. In addition, the dimensions of the center magnet, the peripheral magnet, and the yoke are adjusted.
[0206]
  As a result, the magnetic field generating means is reciprocated in the short side direction of each magnetic circuit on the back side of the backing plate to change the position of the racetrack-like high density plasma on the target surface so that the target erosion progresses uniformly. When a sputtered thin film is formed on a substrate, the substrate generated when the target is completely uniformly eroded in an actual apparatus configuration in which the target is not infinitely larger than the size of the substrate to be deposited The upper film thickness distribution can be corrected.
[0207]
  Further, the magnet unit is configured such that a center magnet and a peripheral magnet are bonded and fixed to a magnet assembly yoke to constitute a magnet assembly, and the magnet assembly is fastened with bolts to a base yoke that forms the entire base of the magnet unit. Therefore, the intensity distribution adjustment on the target surface of the magnetic field generated by the magnet unit is adjusted between the magnet surface and the target surface by fastening the bolt with the auxiliary yoke inserted between the magnet assembly and the base yoke. This can be realized by adjusting the distance.
[0208]
  Further, the fastening holes provided in the magnet assembly yoke of the magnet assembly are elongated holes so that the position of the magnet assembly can be adjusted in the direction of driving the magnetic field generating means on the base yoke. Even if the machining accuracy is not set extremely high, the rectangular short-side pitch P of the portion parallel to the long-side direction of the racetrack-like high-density plasma when the plurality of magnet units are combined is equal. Can be adjusted. That is, the cost of the magnet can be reduced, and desired magnetic field generation means can be easily manufactured by absorbing variations in the magnetic characteristics including the yoke and assembly variations such as adhesion accuracy.
[0209]
  Further, the base yoke and magnet assembly yoke of the magnet assembly, which are constituent members of the magnet unit, are arranged in the longitudinal direction end of the magnet unit where the racetrack-like high-density plasma on the target surface is nearly parallel to the magnetic field generating means driving direction. Since one or both of the base yoke and the magnet assembly yoke are formed thinner than the other portions, the magnetic field is particularly weak with respect to the central portion at the end portion in the perpendicular direction of the magnet unit, that is, the longitudinal end portion of the magnet unit. Can be adjusted as follows.
[0210]
  In addition, the base yoke and the magnet assembly yoke are conductive soft magnetic materials, and the central magnet and the peripheral magnet are conductive magnet materials or have a conductive surface coating, and are magnets that are constituent members of the magnet unit. In the assembly, since the central magnet and the peripheral magnet are fixed to the magnet assembly yoke with a conductive adhesive, the magnetic field generating means is supported by a conductive material, and the composite magnetic circuit is formed by performing the necessary electrical connection. The same potential can be applied to the constituent magnets.
[0211]
  Moreover, the permanent magnet material which comprises the above-mentioned center magnet and a peripheral magnet uses rare earth type magnets (neodymium-iron type, samarium-cobalt type, etc.) as existing magnets having the largest energy product. However, rare earth magnets are fragile and have the disadvantage of poor corrosion resistance. Therefore, if a conductive coating is applied to the surface, the above-mentioned disadvantages can be compensated, and magnet breakage and corrosion can be prevented during the assembly of the magnet unit and the composite magnetic circuit.
[0212]
【The invention's effect】
  BookAs described above, the magnetron sputtering apparatus of the invention is disposed so as to face a rectangular substrate on which a thin film is formed in a vacuum chamber, and has a rectangular target larger than the effective film formation area of the substrate,
  Plasma generating means for generating a plurality of closed racetrack-like high-density plasmas on the surface of the target by performing magnetron discharge on the target;
  Driving means for reciprocally moving the plasma generating means in parallel with either the long side or the short side of the target with respect to the target, and the plasma generating means generates the plasma on the surface of the target. Along the moving direction of the means,The distance between the lines parallel to the major axis among the lines connecting the highest plasma density in one closed racetrack high-density plasmaWhen,Among the lines connecting the highest plasma density portions in a plurality of closed racetrack-like high density plasmas, the distance between the lines parallel to the major axis and the distance between the lines due to different high density racetrack-like plasmas adjacent to each otherThe racetrack-shaped high-density plasma is generated so as to be substantially equal to each other.The distance between the lines parallel to the long axis among the lines connecting the highest plasma density in the racetrack high-density plasma.The plasma generating means is reciprocated at a constant speed with the following amplitude.
[0213]
  Therefore, the plasma generation means is arranged on the surface of the target along the moving direction of the plasma generation means, with the distance between the respective racetrack-like high-density plasmas in the linear region in the major axis direction and the height of the adjacent racetrack-like heights. The racetrack-shaped high-density plasma is generated so that the intervals in the linear region in the major axis direction of the density plasma are substantially equal.
[0214]
  As a result, the power supplied for generating the plasma is dispersed into a plurality of plasmas, so that the power density can be suppressed and a large power supply can be performed without abnormal discharge leading to arc discharge. As a result, the film formation rate can be increased.
[0215]
  Furthermore, the driving means is generatedThe distance between the lines parallel to the long axis among the lines connecting the highest plasma density in the racetrack high-density plasma.Since the above plasma generating means is reciprocated at a constant speed with the amplitude of the following magnitude, the target surface portions eroded by the individual racetrack high density plasma will not overlap, and the target is locally It is possible to eliminate the progression of erosion.
[0216]
  Therefore, according to the magnetron sputtering apparatus having the above configuration, it has a simple mechanism composed of cost-effective parts, and can effectively spend the input power for sputtering of the target, and the use of the target. There is an effect that the efficiency can be kept high and the thickness distribution of the thin film formed on the substrate can be kept within a predetermined range.
[0217]
  Moreover,The interval between the racetrack high-density plasmas is the distance between the highest density portions of the racetrack high-density plasma. When the composite magnetic circuit is reciprocated at a constant speed in the direction in which the magnetic units are arranged. Can be set to be smaller than the distance between the densest portions of the racetrack-shaped high-density plasma, and as a result, the target surface portions eroded by the individual racetrack-shaped high-density plasma overlap. This is advantageous in that the progress of erosion of the target can be locally suppressed.
[0218]
  BookAs described above, the magnetron sputtering apparatus of the present invention is arranged to face a rectangular substrate on which a thin film is formed in the first vacuum chamber, and has a rectangular target larger than the effective film formation area of the substrate, and the target A magnetic field generating means disposed on the back side of the backing plate to be supported and generating a magnetic field on the opposing surface of the target of the substrate, and the magnetic field generating means with respect to the target, the long side or the short side of the target Driving means for reciprocating in parallel with any of the sides, the magnetic field generating means comprising a rectangular magnet unit for generating a magnetic field on the target surface, with the long sides adjacent to each other and the same polarity A plurality of composite magnetic circuits arranged as shown in FIG.The pitch P of the lines parallel to the long side of the magnet unit among the lines connecting the points where the component perpendicular to the target surface of the magnetic field generated on the target surface by one magnet unit becomes zeroOn the other hand, the composite magnetic circuit is moved so that the amplitude SW when the composite magnetic circuit is reciprocated at a constant speed in the direction in which the magnetic units are arranged satisfies the relationship SW ≦ P.And each magnet in the above composite magnetic circuit The units are adjacent to each other at intervals of lines parallel to the long side of the magnet unit among the lines connecting the points where the component perpendicular to the target surface of the magnetic field generated on the target surface by each magnet unit becomes zero. The interval between lines caused by different magnet units is arranged to be equal to the pitch P.It is a configuration.
[0219]
  Therefore, the magnetic field generating means comprises a composite magnetic circuit in which a plurality of rectangular magnet units for generating a magnetic field on the target surface are arranged so that their long sides are adjacent to each other and exhibit the same polarity. Thus, a plurality of closed racetrack-shaped high-density plasmas converged by the generated magnetic field can be obtained on the surface of the target that uses these composite magnetic circuits as a source.
[0220]
  As a result, the power supplied for generating the plasma is dispersed into a plurality of plasmas, so that the power density can be suppressed and a large power supply can be performed without abnormal discharge leading to arc discharge. As a result, the film formation rate can be increased.
[0221]
  Furthermore, the drive meansThe pitch P of the lines parallel to the long side of the magnet unit among the lines connecting the points where the component perpendicular to the target surface of the magnetic field generated on the target surface by one magnet unit becomes zeroOn the other hand, the amplitude SW when the composite magnetic circuit is reciprocated at a constant speed in the direction in which the magnetic units are arranged is set so that the relationship of SW ≦ P is satisfied. The target surface portions that are eroded by the density plasma are not overlapped, and the progress of erosion of the target can be locally suppressed.
[0222]
  BookThe magnetron sputtering apparatus of the invention is as described above.the aboveIn addition to the configuration, the magnet unit includes a central magnet disposed at the center of the unit, and a peripheral magnet disposed so as to surround the central magnet and so that the magnetic poles having the opposite polarity to the central magnet face each other. The pitch of the portion parallel to the long side of the magnet unit among the lines connecting the points where the component perpendicular to the target surface of the magnetic field generated on the target surface by these central magnets and peripheral magnets becomes zero In this configuration, P is formed such that P> MW / 2 with respect to the dimension MW in the short side direction of the magnet unit.
[0223]
  therefore,the aboveIn addition to the effects of the configuration, the magnet unit includes a central magnet arranged at the center of the unit and a peripheral magnet arranged so as to surround the central magnet and so that the magnetic poles having the opposite polarity to the central magnet face each other. Of the part parallel to the long side of the magnet unit in the line connecting the points perpendicular to the target surface of the magnetic field generated on the target surface by these central magnets and peripheral magnets. Since the pitch P is formed so that P> MW / 2 with respect to the dimension MW in the short side direction of the magnet unit, the racetrack-shaped high-density plasma formed by a single magnet unit is formed. The pitch is also larger than MW / 2.
[0224]
  Therefore, the gap between the magnet units is adjusted so that the distance from the racetrack high-density plasma generated in the adjacent magnet unit is equal to the pitch interval of the high-density plasma generated in each magnet unit. There is an effect that can be done.
[0225]
  As described above, in the magnetron sputtering apparatus of the present invention, in addition to the above configuration, the composite magnetic circuit is composed of n (n> 1) magnet units, and each magnet unit is arranged in the direction in which the target magnet units are aligned. Is set to be P = TW / (2 × n + 1), where TW is TW.
[0226]
  According to said structure, in addition to the said effect | action, a composite magnetic circuit consists of n (n> 1) magnet units, and each magnet unit is the above-mentioned of the magnetic field generated on the said target surface by each magnet unit. Of the lines connecting the points where the component perpendicular to the target surface becomes zero, the interval between the lines parallel to the long side of the magnet unit and caused by different magnet units adjacent to each other is equal to the pitch P. And when the dimension of the target magnet unit arrangement direction is TW, P = TW / (2 × n + 1). There is an effect that the eroded areas arranged side by side can be scanned and made uniform by the movement width SW of the magnetic field generating means.
[0227]
  BookThe magnetron sputtering apparatus of the invention is as described above.the aboveIn addition to the configuration, the magnetic field generating means is configured in a second vacuum chamber provided on the surface of the target opposite to the surface facing the substrate.
[0228]
  therefore,the aboveIn addition to the effect of the configuration, the magnetic field generating means is disposed in the second vacuum chamber provided on the surface opposite to the substrate-facing surface of the target, so that the backing plate on which the target is bonded in the apparatus operating state The both sides of the first vacuum chamber (film formation space side) on the target side and the second vacuum chamber (composite magnetic circuit side) on the back side thereof are evacuated.
[0229]
  This eliminates the pressure difference between the two sides of the backing plate to which the target is bonded, which has a substantial mechanical effect, so that the backing plate has the mechanical strength required for bonding to the target and mounting to the device. It is sufficient to have a thickness that can withstand the atmospheric pressure.
[0230]
  BookThe magnetron sputtering apparatus of the invention is as described above.the aboveIn addition to the configuration, the magnetic field generating means disposed in the second vacuum chamber, the driving means for driving the magnetic field generating means, and the second vacuum chamber itself are the same as the target and the backing plate that supports the target. It is the structure set to the electric potential.
[0231]
  therefore,the aboveIn addition to the effects of the configuration, the magnetic field generating means disposed in the second vacuum chamber, the driving means for driving the magnetic field generating means, the second vacuum chamber itself includes the target and a backing plate that supports the target By setting the same potential, the exhaust of the second vacuum chamber provided on the back side of the target in which the magnetic field generating means is accommodated is an oil rotary pump or a so-called “roughing pump” such as a combination of an oil rotary pump and a mechanical booster pump. Even if it is about, when a high voltage is applied to the backing plate to which the target is bonded to cause magnetron discharge for sputtering, the second plate provided on the back side of the target in which the backing plate and the magnetic field generating means are accommodated. There is no discharge between the vacuum chamber and its contents.
[0232]
  Therefore, the pump for exhausting the second vacuum chamber can be a roughing pump as described above. Therefore, an exhaust system including an expensive pump for high vacuum exhaust and various valves for operating the pump is provided. Since it is not necessary, the cost of the apparatus can be reduced.
[0233]
  BookThe magnetron sputtering apparatus of the invention is as described above.the aboveIn addition to the configuration, in the composite magnetic circuit, both ends of the magnet units on the target substrate facing surface have a strong magnetic field with respect to the center, and both ends in the direction orthogonal to the magnet units are in the center. On the other hand, it is the structure adjusted so that a magnetic field may become weak.
[0234]
  therefore,the aboveIn addition to the effect of the configuration, the composite magnetic circuit has a strong magnetic field at both ends of the magnet unit on the surface facing the substrate of the target with respect to the center, and both ends in the direction orthogonal to the magnet unit are in the center. By adjusting so that the magnetic field becomes weaker with respect to the portion, the target can be uniformly eroded and the film thickness distribution on the substrate can be corrected.
[0235]
  Therefore, when the magnet unit is assembled into a composite magnetic circuit, the plasma along the long side of the target is adjusted by adjusting the magnetic field to be stronger with respect to the central part at both ends of the target surface in the magnet unit alignment direction. The density can be increased and the film thickness distribution in the direction in which the magnetic field generating means reciprocates (target short side direction) can be corrected.
[0236]
  Furthermore, the density of the high-density plasma at the long-side end (peripheral portion along the short side of the target) of the rectangular magnet unit is reduced by weakening the magnetic field at the end in the direction perpendicular to the magnet unit with respect to the center. When the magnetic field generating means is reciprocated, the target erosion progress speed is adjusted based on the difference in the plasma residence time on the target surface, and the film thickness distribution can be corrected.
[0237]
  BookThe magnetron sputtering apparatus of the invention is as described above.the aboveIn addition to the configuration, the magnet unit includes a magnet assembly in which a central magnet and a peripheral magnet are bonded and fixed to a magnet assembly yoke, and a base yoke that serves as a base of the entire magnet unit. The fastening hole provided in the magnet assembly yoke is fastened to the base yoke with a bolt, and the diameter of the fastening hole is formed to be larger than the diameter of the bolt.
[0238]
  therefore,the aboveIn addition to the effects of the configuration, the magnet unit includes a magnet assembly in which a central magnet and a peripheral magnet are bonded and fixed to a magnet assembly yoke, and a base yoke that serves as a base of the entire magnet unit. The strength distribution adjustment on the target surface of the magnetic field generated by the magnet unit can be adjusted by fastening the bolt to the base yoke using the fastening holes provided in the magnet assembly yoke. There is an effect that it can be realized by fastening the bolt with the auxiliary yoke inserted between the yoke and the yoke.
[0239]
  BookThe magnetron sputtering apparatus of the invention is as described above.the aboveIn addition to the configuration, the fastening hole of the magnet assembly yoke allows the position of the magnet assembly to be adjusted on the base yoke in the driving direction of the magnetic field generating means when the magnet assembly and the base yoke are fastened. It is the structure currently formed in the long hole.
[0240]
  therefore,the aboveIn addition to the effect of the configuration, the fastening hole of the magnet assembly yoke allows the position of the magnet assembly to be adjusted in the driving direction of the magnetic field generating means on the base yoke when the magnet assembly and the base yoke are fastened. By forming a long hole in the hole, fine adjustment is made so that the pitch in the rectangular short side of the part parallel to the long side direction of the racetrack-shaped high-density plasma becomes equal when a plurality of magnet units are combined. There is an effect that can be done.
[0241]
  BookThe magnetron sputtering apparatus of the invention is as described above.the aboveIn addition to the configuration, at least one of the magnet assembly yoke and the base yoke has a configuration in which a longitudinal end portion of the magnet unit is formed thinner than other portions.
[0242]
  therefore,the aboveIn addition to the effect of the configuration, at least one of the magnet assembly yoke and the base yoke is formed such that the longitudinal end of the magnet unit is thinner than the other portions, so that the magnetic field is at the center of the longitudinal end of the magnet unit. With respect to the above, there is an effect that it can be adjusted to be particularly weak.
[0243]
  BookThe magnetron sputtering apparatus of the invention is as described above.the aboveIn addition to the configuration, the magnet assembly yoke and the base yoke are made of a conductive soft magnetic material, and the central magnet and the peripheral magnet are a conductive magnet material or a magnet material whose surface is coated with a conductive material. The magnet assembly is configured such that the central magnet and the peripheral magnet are fixed to the magnet assembly yoke with a conductive adhesive.
[0244]
  therefore,the aboveIn addition to the effects of the configuration, the magnet assembly yoke and the base yoke are made of a conductive soft magnetic material, and the central magnet and the peripheral magnet are a magnet having a surface coated with a conductive magnet material or a conductive material. The magnet assembly is made of a material, and the center magnet and the peripheral magnet are fixed to the magnet assembly yoke with a conductive adhesive, so that the magnetic field generating means is supported by a conductive substance, and the necessary electrical As a result, the same potential can be achieved up to the magnet surface of the composite magnetic circuit.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a magnetron sputtering apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram for explaining magnetron discharge in a rectangular magnet unit constituting a magnetic field generation mechanism provided in the magnetron sputtering apparatus shown in FIG. 1, wherein (a) is a perspective view of one magnet unit; (b) is a longitudinal sectional view of the magnet unit shown in (a), (c) is an explanatory diagram when glow discharge is performed in combination with a target in the magnet unit shown in (a), and (d) is (c). FIG.
FIGS. 3A and 3B are diagrams showing a high density plasma formation state on a target by a magnetic field generation mechanism of the magnetron sputtering apparatus shown in FIG. 1, wherein FIG. 3A is a plan view, and FIG. 3B is a magnetic field generation of FIG. It is a longitudinal cross-sectional view of the mechanism.
4A is a plan view of a magnetic field generation mechanism of the magnetron sputtering apparatus shown in FIG. 1, and FIG. 4B is a side view of the magnetic field generation mechanism shown in FIG.
5A is an enlarged view of a main part of the magnetic field generating mechanism shown in FIG. 4A, and FIG. 5B is a cross-sectional view of FIG.
6 is a diagram showing various configuration examples of a magnet unit constituting the magnetic field generation mechanism of the magnetron sputtering apparatus shown in FIG. 1, wherein (a) is a plan view and (b) is a short direction of the magnet unit. Vertical sectional view, (c) is a sectional view perpendicular to the short direction of the magnet unit in which the auxiliary plate is inserted at two locations in the longitudinal direction, and (d) is an auxiliary plate inserted at only one central portion in the longitudinal direction. It is sectional drawing perpendicular | vertical to the transversal direction of a magnet unit.
FIG. 7 is a schematic configuration diagram showing another example of a magnetic field generation mechanism provided in the magnetron sputtering apparatus of the present invention.
FIGS. 8A to 8C are explanations of a case where the relationship between the pitch P between the magnet units constituting the magnetic field generation mechanism and the width MW in the short direction of the magnet units is P> MW / 2. FIG.
FIGS. 9A to 9C are diagrams for the case where the relationship between the pitch P between the magnet units constituting the magnetic field generation mechanism and the width MW in the short direction of the magnet units is P <MW / 2. FIG.
FIG. 10 shows the size TW in the short direction of the magnetic field generating mechanism in which a plurality of magnet units are arranged and the high density plasma among the target dimensions when the high density plasma is generated on the target by the magnetic field generating mechanism of the present invention. It is explanatory drawing which shows the case where the pitch P of the part parallel to the longitudinal direction of this magnet unit satisfy | fills the relationship of P = TW / (2 * n + 1).
FIG. 11 is a diagram showing a state in which a target is eroded by high-density plasma generated from the magnetic field generation mechanism of the present invention, and (a) shows the case where the erosion progressing speed is the same at all erosion positions of the target. Explanatory drawing which shows the target erosion situation when the magnetic field generation mechanism is stopped and magnetron discharge is performed, (b) is the case of (a), reciprocating the magnetic field generation mechanism with an amplitude that does not overlap the erosion position of the adjacent target FIG. 6C is an explanatory diagram showing the state of target erosion when the erosion speed is higher than the others at the target erosion positions corresponding to the magnet units at both ends, and the magnetic field generation mechanism is stationary and the magnetron discharge is performed. Explanatory drawing showing the erosion situation of the target, (d) is the case of (c), the magnetic field generation mechanism was reciprocated with an amplitude that the erosion position of the adjacent target does not overlap It is an explanatory view showing a Kino target erosion conditions.
FIG. 12 is a graph showing the results of a film thickness distribution simulation of a thin film formed on the substrate surface based on the cosine law, and is a three-dimensional graph when there is a film thickness distribution.
FIG. 13 is a graph showing the result of a film thickness distribution simulation of a thin film formed on the substrate surface based on the cosine law, and is a three-dimensional graph when the film thickness distribution is corrected.
FIG. 14 is a schematic sectional view of a conventional magnetron sputtering apparatus.
FIG. 15 is a cross-sectional view of a main part of a film forming chamber of another conventional magnetron sputtering apparatus.
FIG. 16 is a perspective view of an essential part of a film forming chamber of still another conventional magnetron sputtering apparatus.
FIG. 17 is a schematic cross-sectional view of still another conventional magnetron sputtering apparatus.
FIGS. 18A to 18C are explanatory views showing the positional relationship between a magnetic circuit unit and a target provided in still another conventional magnetron sputtering apparatus. FIGS.
FIG. 19 shows the relationship between a magnetic circuit unit and a target provided in still another conventional magnetron sputtering apparatus, (a) is a plan view of the magnetic circuit unit, (b) is a plan view of the target, and (c). FIG. 4 is a cross-sectional view showing a state in which the target shown in FIG.
FIG. 20 shows a magnetic circuit unit provided in still another conventional magnetron sputtering apparatus, (a) is a perspective view of a magnetic circuit unit composed of one magnetic circuit, and (b) is a plurality of magnetic circuits. It is a top view of the magnetic circuit unit comprised.
FIG. 21 shows still another conventional magnetron sputtering apparatus, (a) is a schematic longitudinal sectional view of a rectangular magnetic circuit unit provided in the magnetron sputtering apparatus, and (b) is provided in the magnetron sputtering apparatus. It is a short direction schematic sectional drawing of a rectangular-shaped magnetic circuit unit.
FIG. 22 shows still another conventional magnetron sputtering apparatus, (a) is a schematic sectional view of the magnetron sputtering apparatus, and (b) is a plane of a magnetic circuit unit provided in the magnetron sputtering apparatus shown in (a). FIGS. 2A and 2C are explanatory views showing the positional relationship between the magnetic circuit unit and target provided in the magnetron sputtering apparatus shown in FIG.
FIG. 23 is a longitudinal sectional view of a magnetic circuit unit showing an erosion state of a rectangular target eroded by a magnetic circuit unit composed of a plurality of conventional magnetic circuits, and FIG. (B) is a longitudinal cross-sectional view showing the erosion state of the target when the magnetic circuit unit has an amplitude P1 in the longitudinal direction of the target, and (c) is a longitudinal cross-sectional view showing the erosion state of the target. Sectional view in the longitudinal direction showing the state of erosion of the target when the magnetic circuit unit is amplified by the amplitude P2 in the longitudinal direction of the target. FIG. FIG. 6E is a longitudinal sectional view showing the state, and FIG. 5E shows the target when the magnetic circuit unit has an amplitude P4 in the longitudinal direction of the target. It is a longitudinal sectional view illustrating a erosion state.
FIG. 24 is a perspective view showing an erosion state of a target by a conventional magnetron sputtering apparatus.
[Explanation of symbols]
  1 Deposition chamber (first vacuum chamber)
  2 Magnet room (second vacuum chamber)
  3 Substrate
  4 Target
  6 Backing plate (plasma generating means)
  7 Magnetic field generation mechanism (plasma generation means, magnetic field generation means)
  8. Drive device (drive means)
17 Power supply (plasma generating means)
30 Magnet unit
31 Center magnet
32 Peripheral magnet
33 York
34 Magnetic field lines
35 Electric field
36 High density plasma (race track high density plasma)
41 Base yoke
42 Magnet assembly yoke for central magnet
43 Magnet assembly yoke for peripheral magnets
44 Magnet assembly for central magnet
45 Magnet assembly for peripheral magnets
46 volts
47 Fastening hole

Claims (11)

A rectangular target disposed opposite to a rectangular substrate on which a thin film is formed in a vacuum chamber, and having a larger target deposition area than the substrate;
Plasma generating means for generating a plurality of closed racetrack-like high-density plasmas on the surface of the target by performing magnetron discharge on the target;
Driving means for reciprocating the plasma generating means in parallel with either the long side or the short side of the target with respect to the target;
The plasma generating means has a major axis out of the lines connecting the highest plasma density portions in one closed racetrack high density plasma along the moving direction of the plasma generating means on the surface of the target. The distance between the parallel lines and the line connecting the highest plasma density portions of the plurality of closed racetrack-like high-density plasmas. A racetrack-like high-density plasma is generated so that the resulting line-to-line spacing is substantially equal,
The driving means moves the plasma generating means at a constant velocity with an amplitude having a magnitude equal to or smaller than the interval between lines parallel to the major axis among the lines connecting the highest plasma density portions in the generated racetrack high density plasma. A magnetron sputtering apparatus characterized by reciprocating. A rectangular target disposed opposite to a rectangular substrate on which a thin film is formed in the first vacuum chamber, and having a larger target deposition area than the substrate;
A magnetic field generating means disposed on the back side of a backing plate for supporting the target, and generating a magnetic field on the opposing surface of the substrate of the target;
Driving means for reciprocating the magnetic field generating means with respect to the target in parallel with either the long side or the short side of the target;
The magnetic field generating means includes
A rectangular magnet unit for generating a magnetic field on the target surface is composed of a composite magnetic circuit in which a plurality of long sides are adjacent to each other and have the same polarity.
The driving means is
Of the lines connecting the points where the component perpendicular to the target surface of the magnetic field generated on the target surface by the one magnet unit becomes zero, the composite is applied to the pitch P of the line parallel to the long side of the magnet unit. The amplitude SW when the magnetic circuit is reciprocated at a constant speed in the direction in which the magnetic units are arranged moves the composite magnetic circuit so that the relationship SW ≦ P is satisfied,
And each magnet unit in the said composite magnetic circuit is parallel to the long side of the said magnet unit among the lines which connect the point perpendicular | vertical to the said target surface of the magnetic field generated on the said target surface by each magnet unit becoming zero. The magnetron sputtering apparatus is characterized in that the intervals between the lines, which are caused by different magnet units adjacent to each other, are arranged to be equal to the pitch P. The magnet unit is composed of a central magnet arranged at the center of the magnet unit, and a peripheral magnet arranged so as to surround the central magnet and so that a magnetic pole having a polarity opposite to that of the central magnet is opposed. The pitch P of the portion parallel to the long side of the magnet unit among the lines connecting the points perpendicular to the target surface of the magnetic field generated on the target surface by the central magnet and the peripheral magnet becomes zero, 3. The magnetron sputtering apparatus according to claim 2 , wherein the magnet unit is formed so that P> MW / 2 with respect to a dimension MW in the short side direction of the magnet unit. The combined magnetic circuit includes a magnet unit of n (n> 1), each magnet unit, the magnet unit arrangement direction of the dimension of the upper Symbol target when the TW, P = TW / (2 × n + 1) The magnetron sputtering apparatus according to claim 2 , wherein the magnetron sputtering apparatus is set to be 5. The magnetron sputtering apparatus according to claim 2, wherein the magnetic field generating means is disposed in a second vacuum chamber provided on a surface opposite to the substrate-facing surface of the target . The magnetic field generating means disposed in the second vacuum chamber, the driving means for driving the magnetic field generating means, and the second vacuum chamber itself are set to the same potential as the target and the backing plate that supports the target. The magnetron sputtering apparatus according to claim 5, wherein In the composite magnetic circuit, both ends of the magnet unit on the target substrate facing surface in the direction of arrangement of the magnet units have a strong magnetic field with respect to the center, and both ends in the direction perpendicular to the direction of arrangement of the magnet units have a weak magnetic field with respect to the center. The magnetron sputtering apparatus according to claim 2, wherein the magnetron sputtering apparatus is adjusted so as to become . The magnet unit is composed of a magnet assembly in which a central magnet and a peripheral magnet are bonded and fixed to a magnet assembly yoke, and a base yoke that serves as a base of the entire magnet unit.
The magnet assembly is fastened to the base yoke with a bolt using a fastening hole provided in the magnet assembly yoke,
8. The magnetron sputtering apparatus according to claim 7, wherein a diameter of the fastening hole is formed to be larger than a diameter of the bolt . The fastening hole of the magnet assembly yoke is formed in a long hole so that the position of the magnet assembly can be adjusted on the base yoke in the driving direction of the magnetic field generating means when the magnet assembly and the base yoke are fastened. The magnetron sputtering apparatus according to claim 8 , wherein the magnetron sputtering apparatus is provided. The magnetron sputtering apparatus according to claim 8 or 9, wherein at least one of the magnet assembly yoke and the base yoke is formed such that a longitudinal end portion of the magnet unit is thinner than other portions . The magnet assembly yoke and the base yoke are made of a conductive soft magnetic material,
The central magnet and the peripheral magnet are composed of a conductive magnet material or a magnet material whose surface is coated with a conductive material,
11. The magnetron sputtering apparatus according to claim 8, wherein the magnet assembly includes a central magnet and a peripheral magnet fixed to the magnet assembly yoke with a conductive adhesive .

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