Abstract:
To uniformly perform processing such as deposition on a processing object such as a large, heavy substrate for optics, the large, heavy substrate for optics is accurately, reliably attached to a holder. A vacuum processing apparatus which processes a processing object in a vacuum vessel includes a susceptor which has a surface having concavity and convexity, that is opposite to its surface on which the processing object is mounted, and movably holds the processing object, a holder which has a surface having concavity and convexity which mesh with those of the susceptor, a driving mechanism which holds the holder to be movable to a first state or a second state, and a control means for moving the susceptor while the holder is held in the first state to mesh the surface, having the concavity and convexity, of the susceptor with the surface, having the concavity and convexity, of the holder and thereby connect the susceptor and the holder to each other, moving the holder, to which the susceptor is connected, to the second state and processing the processing object, and moving the holder to the first state again and moving the susceptor so that the surface, having the concavity and convexity, of the susceptor is separated from the surface, having the concavity and convexity, of the holder.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a vacuum processing apparatus and an optical component manufacturing method. 
       BACKGROUND ART 
       [0002]    In recent years, with an increase in the size of semiconductor substrates and image display devices, optical components such as large lenses and mirrors are often employed in lithographic techniques for forming patterns on them. These optical components normally have surfaces which are processed or on which a variety of thin films such as coating films are formed. 
         [0003]    A sputtering method is employed to uniformly deposit a multilayer film on a substrate for a concave/convex optical system used in, for example, an exposure machine. Setting the target area of a cathode for use in sputtering smaller than the substrate allows an improvement in use efficiency of the target and deposition which is suitable for the three-dimensional patterns of various types of substrates and is impossible when a large target is used. 
         [0004]    To uniformly deposit a multilayer film on a substrate for a concave/convex optical system, the distance (TS distance) between the target and the substrate for optics must be kept constant. To achieve this, PTL1 discloses a technique of controlling three or more axes such as the rotation axis of the cathode and the spin axis and scan axis of the substrate. 
         [0005]    Also, PTL2 discloses a technique of adjusting the pressure in accordance with the distance between a target and a substrate for an optical system. 
       CITATION LIST 
     Patent Literature 
       [0000]    
       
         PTL1: Japanese Patent Laid-Open No. 2004-269988 
         PTL2: Japanese Patent Laid-Open No. 2007-182617 
       
     
       SUMMARY OF INVENTION 
     Technical Problem 
       [0008]    To uniformly deposit a multilayer film on a substrate for concave/convex optics, the TS distance must be kept constant on the order of several micrometers to several tens of micrometers. 
         [0009]    However, in the prior arts, the relative position accuracy between the target and the substrate is on the order of several hundreds of micrometers, and does not satisfy the required accuracy. Moreover, with further increases in size and weight of substrates for optics in the future, the position accuracy is expected to further deteriorate. 
         [0010]    It is expected that in the near future, a substrate for optics that requires processing will have a larger size and the total weight of the substrate and a transport jig attached to it will become as heavy as 500 kg. At the same time, the relative position accuracy between the target and the substrate must improve by one to two orders of magnitude. 
         [0011]    The present invention has been made in consideration of the above-mentioned problem, and realizes a technique to accurately, reliably attach a large, heavy substrate for optics to a holder in order to uniformly perform processing such as deposition on a processing object such as the large, heavy substrate for optics. 
       Solution to Problem 
       [0012]    In order to solve the above-mentioned problem, the present invention provides a vacuum processing apparatus that processes a processing object in a vacuum vessel, comprising a susceptor that has a surface having projections and grooves, that is opposite to a surface thereof on which the processing object is mounted, and movably holds the processing object, a holder which has a surface having projections and grooves which mesh with the projections and grooves of the susceptor, a driving mechanism which holds the holder such that the holder can move so as to assume one of a first state and a second state, and control means for moving the susceptor while the holder is held in the first state to mesh the surface, having the projections and grooves, of the susceptor with the surface, having the projections and grooves, of the holder and thereby connect the susceptor and the holder to each other, moving the holder, to which the susceptor is connected, so as to assume the second state to process the processing object, and moving the holder so as to assume the first state again to move the susceptor so that the surface, having the projections and grooves, of the susceptor is separated from the surface, having the projections and grooves, of the holder. 
         [0013]    In order to solve the above-mentioned problem, there is also provided an optical component manufacturing method comprising the step of processing the processing object using the vacuum processing apparatus according to the present invention. 
       Advantageous Effects of Invention 
       [0014]    According to the present invention, it is possible to uniformly perform processing such as deposition on a large, heavy processing object. 
         [0015]    Other features and advantages of the present invention will be apparent from the following descriptions taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0016]    The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
           [0017]      FIG. 1A  is a plan view showing the schematic arrangement of a vacuum processing apparatus in an embodiment according to the present invention; 
           [0018]      FIG. 1B  is a side view showing the schematic arrangement of the vacuum processing apparatus in the embodiment according to the present invention; 
           [0019]      FIG. 2A  is a plan view showing the schematic arrangement of a deposition chamber of the vacuum processing apparatus in the embodiment according to the present invention; 
           [0020]      FIG. 2B  is a side view showing the schematic arrangement of the deposition chamber of the vacuum processing apparatus in the embodiment according to the present invention; 
           [0021]      FIG. 2C  is a side view showing the schematic arrangement of the deposition chamber of the vacuum processing apparatus in the embodiment according to the present invention; 
           [0022]      FIG. 3  is a view showing the schematic arrangement of a chucking mechanism of the vacuum processing apparatus in the embodiment according to the present invention; and 
           [0023]      FIG. 4  is a view for explaining adjustment of the distance between a target and a processing object in the embodiment according to the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0024]      FIG. 1A  is a plan view showing a vacuum processing apparatus in an embodiment according to the present invention. 
         [0025]    Referring to  FIG. 1A , reference numeral  101  denotes a balancer device;  102 , an elevator chamber;  103 , a load lock chamber;  104 , a deposition chamber;  105 , gate valves which shield the load lock chamber  103  against the atmospheric air or shield the load lock chamber  103  and the deposition chamber  104  from each other;  106 , a spindle;  107 , a cathode unit;  108 , controllers which control the individual units;  109 , a host controller which performs overall control;  112 , a carriage; and  120 , a processing object. 
         [0026]      FIG. 1B  is a side view showing a vacuum processing apparatus  100  in the embodiment according to the present invention. The same reference numerals as in  FIG. 1A  denote the same constituent elements in  FIG. 1B , and a description thereof will not be given. Constituent elements that have not been described with reference to  FIG. 1A  are a susceptor  121  on which the processing object  120  is fixed and which is used to transport the processing object  120 , a transport chamber  110  disposed on the deposition chamber  104 , a transfer mechanism  111  which exchanges the processing object  120  and susceptor  121  with the spindle  106  in the transport chamber  110 , and a carriage transport rail  113  serving as a transport line along which the carriage  112  which mounts the processing object  120  and susceptor  121  is transported among the elevator chamber  102 , the load lock chamber  103 , and the transport chamber  110 . In this embodiment, the load lock chamber  103 , transport chamber  110 , and deposition chamber  104  are evacuated to a low pressure by an exhaust means (not shown). 
         [0027]    On a position adjusting table  101   b  of the balancer device  101 , matching of the rotation center axes of the processing object  120  and the susceptor  121  which are integrated with each other and the position of the processing object  120  relative to the susceptor  121  are measured by, for example, a laser distance sensor, and the processing object  120  and susceptor  121  are adjusted to align themselves on the same rotation axis. The processing object  120  is made of glass when it is an optical component such as a lens or a mirror. The processing object  120  is fixed by a jig (not shown) on the susceptor  121  for transporting the processing object  120 . 
         [0028]    A dynamic balancer adjusting table  101   a  rotates the processing object  120  and the susceptor  121  which are integrated with each other to confirm whether their dynamic balance falls within a tolerance. If the dynamic balance falls outside the tolerance, it is corrected using, for example, a weight. 
         [0029]    After the dynamic balance of the processing object  120  and susceptor  121  is determined to fall within the tolerance, the susceptor  121  on which the processing object  120  is fixed is delivered to the lower portion of the elevator chamber  102 , is placed on an arm (not shown) provided in the elevator chamber  102 , and ascends to the upper portion of the elevator chamber  102 . 
         [0030]    The position adjusting table  101   b , the dynamic balancer adjusting table  101   a , and the lower portion of the elevator chamber  102  will be collectively referred to as the balancer device  101  throughout the specification. 
         [0031]    The transport rail  113  along which the carriage  112  reciprocates is set in the upper portion of the elevator chamber  102 , the load lock chamber  103 , and the transport chamber  110 . The transport rail  113  is used to transport the carriage  112 , which mounts the processing object  120  and susceptor  121 , between the elevator chamber  102  and the transport chamber  110  while guiding the carriage  112  using its own guiding function. 
         [0032]    An arm (not shown) is provided in the elevator chamber  102 . When the susceptor  121  is transported into the elevator chamber  102  by the balancer device  101 , the transfer portion of the arm which has been retracted is moved to a position immediately below the susceptor  121 . After that, the arm ascends and receives the susceptor  121 , and the susceptor  121  ascends, together with the arm. Upon the ascent, the susceptor  121  temporarily ascends up to a position higher than the carriage  112  present on the transport rail  113 . The carriage  112  that has been retracted in the load lock chamber  103  moves to the elevator chamber  102  and stops at a position immediately below the susceptor  121 . 
         [0033]    The susceptor  121  on which the processing object  120  is fixed descends by means of the arm in the elevator chamber  102  up to the level at which it is mounted on the carriage  112 , and the processing object  120  and susceptor  121  are transferred from the transfer portion of the arm onto the carriage  112 . Note that after transferring the susceptor  121  onto the carriage  112 , the arm horizontally moves and retracts from the position immediately below the susceptor  121 . 
         [0034]    Since the arm in the elevator chamber  102  blocks or hampers transportation of the carriage  112  into the load lock chamber  103 , it temporarily ascends for retraction. The carriage  112 , which mounts the susceptor  121  on which the processing object  120  is fixed, is transported from the elevator chamber  102  into the load lock chamber  103 . The gate valve  105  is present between the elevator chamber  102  and the load lock chamber  103 , and can shield the interior of the load lock chamber  103  against the atmospheric air. The controller  108  of the balancer device  101  controls the foregoing processes under the supervision of the host controller  109 . 
         [0035]    In this embodiment, the load lock chamber  103  is connected to a vacuum pump (not shown) with high mass-exhaust performance so as to be evacuated up to a sufficiently low pressure (for example, a pressure of 10E-4 Pa or less). Also, a means for heating the load lock chamber  103  is desirably provided in order to prevent water from reaching the downstream side of the gate valve  105 . 
         [0036]    When the pressure of the load lock chamber  103  sufficiently drops, the gate valve  105  between the load lock chamber  103  and the transport chamber  110  opens. The carriage  112  which mounts the susceptor  121  on which the processing object  120  is fixed moves into the transport chamber  110 . When the carriage  112  enters the transport chamber  110  and reaches a position above the spindle  106  in the deposition chamber  104 , it stops and then the gate valve  105  between the load lock chamber  103  and the transport chamber  110  closes. The controller  108  of the load lock chamber  103  controls the foregoing processes under the supervision of the host controller  109 . 
         [0037]    In the transport chamber  110 , the susceptor  121  on which the processing object  120  is fixed is transferred from the carriage  112  to the spindle  106 . The distal end portions of the transfer mechanism  111  descend to a position slightly lower than the lower surface of the susceptor  121  mounted on the carriage  112 . The distal end portions of the transfer mechanism  111  rotate and thereupon enter a clearance immediately below the susceptor  121 . The distal end portions of the transfer mechanism  111  ascend, so the susceptor  121  ascends up to a position higher than the carriage  112 . After that, the gate valve  105  between the load lock chamber  103  and the transport chamber  110  opens, the carriage  112  retracts into the load lock chamber  103 , and the gate valve  105  closes. 
         [0038]    In accordance with almost the reverse procedure to the processes performed in the elevator chamber  102 , the susceptor  121  on which the processing object  120  is fixed is transferred to and supported by the transfer mechanism  111 . The susceptor  121  on which the processing object  120  is fixed descends by means of the transfer mechanism  111 . When the susceptor  121  comes close to the spindle  106  at a lower position, a curvic coupling on the susceptor  121  and that mounted on a holder at the distal end of the spindle  106  start to mesh with each other, and the axis of the processing object  120  and susceptor  121  finally automatically coincides with the corresponding axis of the spindle  106 . 
         [0039]    A curvic coupling is fixed on the surface of the susceptor  121 , which is opposite to the processing object  120 . A curvic coupling is also fixed on the holder at the distal end of the spindle  106 . These curvic couplings have sets of tapered teeth, so the sets of teeth normally finally mesh with each other in a self-aligning manner even if their positions shift from each other within the range of about ±1.5 mm. Hence, there is no need to accurately position the transfer mechanism  111  in mounting the susceptor  121  on the spindle  106 . 
         [0040]    Also, when the susceptor  121  is transported such that a predetermined position defined on it always faces a constant phase direction to allow the teeth of the curvic coupling on the susceptor  121  to always mesh with the same, corresponding teeth of the spindle  106  each time, a higher position reproducibility of the processing object  120  and susceptor  121  relative to the spindle  106  can be obtained. 
         [0041]    Note that the curvic couplings have a pair of concave and convex teeth formed on them. It is especially preferable to coaxially annularly, radially form the pair of teeth because these two members coaxially couple together upon engaging the tooth groove which is annularly, radially formed in one surface of one member with that which is annularly, radially formed in the corresponding surface of the other member, thereby exhibiting a self-aligning function. The tops of the tooth grooves are truncated in many cases. 
         [0042]    The processing object  120  and the susceptor  121  on which it is fixed are attracted to the spindle  106  by a chucking mechanism provided at the distal end of the spindle  106  so as to prevent the sets of teeth of the curvic couplings from disengaging from each other upon rotating the susceptor  121 , on which the processing object  120  is fixed, to stand upright from a horizontal state (first state) to a vertical state (second state) (upon moving the spindle  106  from a vertical position to a horizontal position) or upon spinning the elevator chamber  102 . The attraction force is weak enough not to deform the processing object  120  and strong enough not to remove the susceptor  121  from the spindle  106  during rotation. 
         [0043]    The cathode unit  107  controlled by the host controller  109  and the controller  108  of the cathode unit  107  uniformly performs deposition processing on the processing object  120  which assumes a vertical state. 
         [0044]    After the processing is completed, the processing object  120  and the susceptor  121  on which the processing object  120  is fixed can be recovered by performing the above-mentioned operations in reverse order in principle. That is, the spindle  106  is rotated from a horizontal position to a vertical position to move the susceptor  121 , on which the processing object  120  is fixed, from a vertical state to a horizontal state, and the susceptor  121  on which the processing object  120  is fixed is lifted by the transfer mechanism  111  to separate it from the spindle  106  meshing with it via the curvic couplings. The controllers  108  of the transport chamber  110  and spindle  106  control the foregoing processes under the supervision of the host controller  109 . 
         [0045]      FIGS. 2A to 2C  are views showing the schematic arrangement of the deposition chamber  104  shown in  FIGS. 1A and 1B . A deposition chamber  204  will be described with reference to  FIGS. 2A to 2C .  FIG. 2A  is a plan view of the deposition chamber  204 ,  FIG. 2B  is a sectional side view depicting the state in which a susceptor  221  on which a processing object  220  is fixed faces a cathode unit  207 , and  FIG. 2C  is a side view depicting the state in which a spindle  206  rotates to a vertical position and the susceptor  221  on which the processing object  220  is fixed is separated from a holder  222  by a transfer mechanism  211 . 
         [0046]    Reference numerals with the same last two digits as in  FIGS. 1A and 1B  denote substantially the same constituent elements in  FIGS. 2A to 2C , and a description thereof will not be given. Reference numerals  215   a  and  215   b  denote linear guide rails;  216   a  and  216   b , vacuum-side bases;  217   a  and  217   b , atmospheric-side bases;  218 , a height adjusting block;  222 , the holder;  223 , a curvic coupling;  220 , the processing object;  221 , the susceptor;  231 , a target;  236 , a measuring device;  240 , bellows; and 241, a wire/pipe extension tube used to extend a pipe for supplying isothermal water with a constant temperature and a wire for, for example, a driving motor. Reference numeral  233  denotes the movement direction of the spindle  206 ;  234 , the oscillation direction of the cathode unit  207 ; and  235 , the rotation direction of the holder  222 . 
         [0047]    In this embodiment, the cathode unit  207  has a nearly regular pentagon shape, and the target  231  is attached to it such that the center of the target  231  coincides with that of each side of the cathode unit  207 . Also, the measuring device  236  is attached to one side of the cathode unit  207 . Note that the cathode unit  207  rotates by oscillation in the oscillation direction  234  about its central axis. 
         [0048]    The spindle  206  and cathode unit  207  are mounted on the linear guide rails  215   a  and  215   b , which are supported by the vacuum-side bases  216   a  and  216   b  and atmospheric-side bases  217   a  and  217   b , respectively. 
         [0049]    With the foregoing structure, the cathode unit  207  and spindle  206  can move in linear directions  232  and  233  along the linear guide rails  215   a  and  215   b . Because the spindle  206  and cathode unit  207  are mounted on the vacuum-side bases  216   a  and  216   b  and atmospheric-side bases  217   a  and  217   b , respectively, their mounting surfaces themselves do not deform. Moreover, because minute holes (not shown) are formed in the vacuum-side bases  216   a  and  216   b , and isothermal wafer always flows through these holes, thermal expansion with a change in temperature, for example, does not occur in the vacuum-side bases  216   a  and  216   b  and therefore does not influence moving portions on the vacuum-side bases  216   a  and  216   b , such as the cathode unit  207 , thus obtaining high position reproducibility. 
         [0050]    The holder  222  is attached to the distal end of the spindle  206 . One tooth groove of the curvic coupling  223  is formed in one surface of the holder  222 . 
         [0051]    As has been described with reference to FIGS.  1 A and  1 B, the susceptor  221  on which the processing object  220  having been transported to a position immediately above the spindle  206  by the carriage  112  is fixed is connected to the holder  222  at the distal end of the spindle  206  while the tooth groove of a curvic coupling  223   a  on the susceptor  221  meshes with that of a curvic coupling  223   b  on the spindle  206 . 
         [0052]    After the susceptor  221  on which the processing object  220  is fixed is connected to the holder  222 , the susceptor  221  on which the processing object  220  is fixed is attracted and fixed onto the holder  222  by a chucking mechanism (to be described later). After that, the spindle  206  rotates in a direction  230  in which it falls from a vertical position to a horizontal position by means of a rotating mechanism (not shown) to move the holder  222  from a horizontal state to a vertical state (a state shown in  FIG. 2B ). 
         [0053]    On the other hand, the cathode unit  207  to which the target  231  is attached moves along the linear guide rail  215   b  up to the position at which it squarely faces the spindle  206 . Finally, the processing object  220  squarely faces the target  231  attached to the cathode unit  207 . Also, the susceptor  221  on which the processing object  220  connected to the holder  222  is fixed can be rotated in a rotation direction  235  about its spin axis by a motor built into the spindle  206 . 
         [0054]    The reason why the processing object  220  and susceptor  221  are attached to the holder  222  in a horizontal state and are then rotated to stand upright in the foregoing way will be explained below. 
         [0055]    As has been described first, the weight of the processing object  220  increases with an increase in its size. The total weight of the processing object  220  and the susceptor  221  sometimes exceeds 500 kg. 
         [0056]    In this embodiment, the curvic couplings  223  are used for normal position detection and fixing. As described earlier, when the pair of curvic couplings  223  face each other in a horizontal state, normal position detection can be precisely performed in a self-aligning manner by bringing the tapered surfaces of the curvic couplings  223  into contact with each other. 
         [0057]    On the other hand, when the susceptor  221  is held while the holder  222  stands upright, that is, it is set vertically (a state shown in  FIG. 2B ), the self weights of the processing object  220  and susceptor  221  vertically act on the curvic couplings  223 . In other words, the self weights of the processing object  220  and susceptor  221  act on the tapered surfaces of the curvic couplings  223  vertically, that is, in the direction going into the tooth grooves, so the tapered surfaces of the curvic couplings  223  suffer end tooth bearing and the curvic couplings  223  do not smoothly perfectly mesh with each other. As the weighs of the processing object  220  and susceptor  221  get heavier, it becomes harder for the sets of teeth of the curvic couplings  223  to mesh with each other. Furthermore, as the coefficient of friction increases in a lower-pressure environment (for example, 1,000 Pa or less), it is often the case that the sets of teeth of the curvic couplings  223  do not smoothly mesh with each other. As a result, precise normal position detection becomes more difficult. 
         [0058]    Also, when the curvic couplings  223  are finally made to perfectly mesh with each other by applying a force, with which the susceptor  221  is attracted to the holder  222 , to the susceptor  221  by the chucking mechanism, end tooth bearing as described above hinders the susceptor  221  from being sufficiently attracted to the holder  222 . 
         [0059]    On the other hand, from the viewpoint of reducing the adverse effect of particles, the processing object  220  desirably assumes a vertical state. This is to avoid the adverse effect of adhesion of particles that fall gravitationally. 
         [0060]    The inventor of the present invention took the foregoing fact into consideration, and concluded that when the susceptor  221  is attached to the holder  222  and undergoes normal position detection, both in a horizontal state using the curvic couplings  223 , and is then rotated to assume a vertical state, it is possible to precisely, reliably perform normal position detection and fixing without causing end tooth bearing of the curvic couplings  223 , and to achieve processing that is less subject to particles. Note that when the meshing surfaces of the curvic couplings  223  are coated with lithium-based grease which discharges little gas (for example, Space Lub® ML No. 2 available from Kyodo Yushi Co., Ltd.), they more smoothly mesh with each other, thus improving the reliability. 
         [0061]    The chucking mechanism which attracts and fixes, onto the holder  222 , the susceptor  221  on which the processing object  220  is fixed will be described next with reference to  FIG. 3 . 
         [0062]    Referring to  FIG. 3 , reference numeral  301  denotes a susceptor;  302   a  and  302   b , curvic couplings each having one surface in which a tooth groove is formed;  303 , a holder;  304 , a susceptor-side block;  305 , a holder-side block;  306 , an opening shaft;  307 , a ball; and  308 , a spindle shaft. Although not shown in  FIG. 3 , a processing object is fixed on the surface of the susceptor  301 , which is opposite to that to which the curvic coupling  302   a  is attached. 
         [0063]    The opening shaft  306  at the center of a spindle shaft  308  operates in a closing direction  309  by means of the force of a spring (not shown) inside the spindle shaft  308 . Note that the opening shaft  306  operates in the direction opposite to the closing direction  309  by means of a cylinder mechanism having a thrust larger than the spring force. Note also that the cylinder mechanism is disposed at the distal end of the spindle shaft  308 , and is not shown in  FIG. 3 . 
         [0064]    When the opening shaft  306  operates in the closing direction  309  by means of the spring force, balls  307  arranged at several points in the circumferential direction of the opening shaft  306  are pressed against the opening shaft  306  and holder-side block  305  and thereupon launch toward the susceptor-side block  304 . The launched balls  307  are pushed in the closing direction  309  by the opening shaft  306  and thereupon push the susceptor-side block  304  in the closing direction  309 . That is, the balls  307  push the projecting portion of the susceptor-side block  304  in the closing direction  309 , and the susceptor  301  is attracted to the holder  303  as a result. Thus, the susceptor  301  is attracted to and held by the holder  303 . 
         [0065]    At the same time, the curvic couplings  302   a  and  302   b  mesh with each other to position the rotation center of the spindle shaft  308  and the center of the susceptor  301  by the self-aligning function of the curvic couplings  302   a  and  302   b.    
         [0066]    The force with which the opening shaft  306  operates in the closing direction  309 , that is, the spring force is desirably about 1.7 ton, which is weak enough not to deform the susceptor  301  and strong enough to maintain the susceptor  301  in a vertical state and not to remove it from the holder  303  during rotation. The spring force with this magnitude also acts as the meshing force with which the curvic couplings  302   a  and  302   b  can exhibit their self-aligning function. 
         [0067]    As a method of separating the susceptor  301  from the holder  303 , the above-mentioned operations need only be performed in reverse order in principle. That is, the opening shaft  306  operates in the direction opposite to the closing direction  309  by means of the cylinder mechanism, the susceptor-side block  304  is released from restriction of the balls  307 , and the susceptor  301  is separated from the holder  303  by the transfer mechanism  211 . 
         [0068]    An arrangement, which keeps the distance between a target and the surface of a processing object constant, will be described next with reference to  FIG. 4 . 
         [0069]    Referring to  FIG. 4 , reference numeral  401  denotes a cathode unit;  402 , a cathode;  403 , a target;  404 , a processing object; and  405 , a spindle. Although the processing object  404  is attached to a susceptor by a jig (not shown) and the susceptor is connected to a holder attached to the distal end of the spindle  405  in practice, the susceptor and the holder are not shown in  FIG. 4  for the sake of descriptive convenience. 
         [0070]    The cathode unit  401  is mounted on the linear guide rail  215   b  and can move in a linear direction  411 , rotate about its central axis, and perform oscillating rotation  410 , as has been described with reference to  FIGS. 2A to 2C . On the other hand, the spindle  405  is mounted on the guide rail and can move in a linear direction  413 . 
         [0071]    The cathode  402  is attached to each side of the cathode unit  401 , which has a regular pentagon shape and to which a plurality of cathodes  402  can be attached, to make it possible to form a multilayer film. The target  403  is attached to the surface of the cathode  402 . A magnet (not shown) which produces an asymmetric magnetic field spins about the central axis of the target  403  inside the cathode  402 , thereby uniformly sputtering the target  403 . 
         [0072]    A method in which the distance between the processing object  404  and the surface of the target  403  is set with the above-mentioned arrangement to a predetermined value as a condition indispensable to uniformly performing deposition on the processing object  404  will be described. 
         [0073]    A measuring device  406  which measures the distance is buried in one surface of the cathode unit  401 . The measuring device  406  includes a built-in laser emitting device and can measure the distance between the processing object  404  and one surface of the cathode unit  401  by detecting, using the light-receiving portion of the measuring device  405 , laser light which is emitted by the laser emitting device and reflected by the surface of the processing object  404 . 
         [0074]    When the size of the target  403  is measured in advance, the distance between an arbitrary target  403  and the processing object  404  can be determined based on the measurement value obtained by the measuring device  406 . Hence, the distance between the target  403  and the processing object  404  can be set to a predetermined value  420  by moving the spindle  405  in the linear direction  413  based on the determined value of the distance. 
         [0075]    Although an embodiment according to the present invention has been described above, the present invention is not particularly limited to this embodiment. Also, although a concave optical component has been exemplified as the processing object, the present invention is also applicable to convex and planar optical components. 
         [0076]    Further, although sputter deposition processing has been exemplified in this embodiment, the present invention is also applicable to a vacuum processing apparatus which performs, for example, preprocessing, post-processing, or etching processing using an ion source or radical source which is compact relative to a processing object. 
         [0077]    The present invention is not limited to the above-described embodiments, and various changes and modifications can be made within the spirit and scope of the present invention. Therefore, to apprise the public of the scope of the present invention, the following claims are made. 
         [0078]    This application claims the benefit of Japanese Patent Application No. 2009-136859, filed Jun. 8, 2009, which is hereby incorporated by reference herein in its entirety.