Abstract:
An arrangement for moving a carrier within a vacuum chamber is described. This carrier is formed in the shape of a plate and is supported with its narrow-side lower edge on rollers driven by a drive system. As a drive system uses a magnetic coupling which is disposed partially within the vacuum chamber and partially outside of the vacuum chamber. With the aid of a force acting in the vertical direction the two components of the magnetic coupling can be displaced relative to one another. In addition, horizontal displacement of the carrier is also possible.

Description:
BACKGROUND 
       [0001]    The invention relates to substrate transfer in a chamber. 
         [0002]    In vacuum coating installations operating according to the PECVD principle (PECVD=Plasma Enhanced Chemical Vapor Deposition) the coating takes place directly via the gas introduced into the installation and ionized by a source. A plasma burns between the source and a substrate or a back electrode disposed behind the substrate. 
         [0003]    The substrates are often fastened on a carrier which is moved on rollers through the vacuum coating installation. These rollers are moved by drive systems preferably located outside of the vacuum coating installation such that no contaminations occur in the coating installation. 
         [0004]    A driving arrangement for a shaft located in a chamber is already known (US 2005/0206260 A1). This shaft is driven via a magnetic coupling by means of a motor located outside of the chamber. 
         [0005]    Moreover, a transport arrangement for substrates in vacuum coating installations with several transport rollers is known (DE 103 28 273 A1). In this arrangement the drive as well as also the transport rollers are located in the evacuated region of the coating installation. 
         [0006]    A process chamber is furthermore known which comprises a transport system for workpieces (GB 2 171 119 A). This transport system includes cylinders driven by a magnetic coupling. The magnetic coupling serves herein for switching between two sets of transport rollers disposed on a lift within the chamber. 
         [0007]    Further known is an arrangement for moving mounting parts in vacuum installations, which comprises a connection element within a volume, which element is partially comprised of a magnetic material, wherein outside of the volume also a magnetic material is disposed which is exclusively in contact with the inner magnetic material via frictional connection (DE 102 27 365=EP 1 387 473 A2). 
         [0008]    In a known method for treating laminar substrates, such as silicon disks, in vertical orientation for the production of micro-electrical structural elements, driving rollers are provided which are pressed onto three sites of a circular silicon disk (U.S. Pat. No. 6,251,551 B1). This silicon disk can be rotated about its axis by means of the driving rollers. However, the linear further transporting of the silicon disk takes place with the aid of a conveyor belt. 
         [0009]    For the rotation movement of a plate-shaped and circular carrier it is known to provide several rollers which engage on the margin of the carrier (JP 2002 110763 A). However, the linear movement of the carrier takes place via rails. 
         [0010]    A magnetic carrier arrangement with a spiral-magnetic coupling is disclosed in US 2002/0060134 A1. This arrangement, however, does not provide a lifting mechanism for rollers. 
         [0011]    EP 1 648 079 A2 describes a system for the transmission of movement between objects separated by a wall. This system is not suitable for the transport of carriers. 
         [0012]    Lastly, a vacuum coating installation with transport rollers for the transport of a laminar substrate is known, which comprises a drive system located outside of the vacuum coating installation and at least one magnetic coupling between the drive and at least one transport roller (not previously published European Patent Application EP 1 870 487). 
       SUMMARY 
       [0013]    The devices described herein address the problem of automatically moving objects within a chamber in at least one direction. 
         [0014]    This problem is solved using an arrangement of a carrier in the shape of a plate and linearly movable by driving rollers, where the driving rollers are moved by a lifting mechanism toward and away from a narrow side of a plate shaped carrier. 
         [0015]    Consequently, an arrangement for moving a carrier within a vacuum chamber is described. This carrier can be formed in the shape of a plate and disposed with its narrow-side lower edge on rollers driven by a drive system. A magnetic coupling, which is located partially within the vacuum chamber and partially outside of the vacuum chamber, can serve as the indirect drive. A component of the magnetic coupling can be located outside of the vacuum chamber being driven by a motor. With the aid of a force acting in the vertical direction, the two components of the magnetic coupling can be displaced relative to one another. Horizontal displacement of the carrier is, in addition, also possible. 
         [0016]    One advantage attained with the arrangement is that carriers within a vacuum coating installation can be separated from driving rollers bearing the carriers. A further advantage can be that the carriers can also be displaced laterally. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES  
         [0017]    An example embodiment is depicted in the drawing and will be described in further detail in the following. The drawings depict: 
           [0018]      FIG. 1  an overall view of a process chamber, 
           [0019]      FIG. 2  a longitudinal section A-A through the process chamber of  FIG. 1 , 
           [0020]      FIG. 3  an enlarged partial representation from  FIG. 2  in a first position, 
           [0021]      FIG. 4  an enlarged partial representation from  FIG. 2  in a second position and 
           [0022]      FIG. 5  a portion of a longitudinal section B-B through the process chamber of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION  
       [0023]      FIG. 1  shows a process chamber  1  in side view. Besides this process chamber  1  can be located further, not shown, chambers. These chambers can be process and/or buffer chambers. 
         [0024]    The process chamber  1  rests on feet  2 ,  3  between which a gearing  29 , with toothed wheels  4 ,  5 ;  6 ,  7  and counter shafts  8 ,  9 , is located. 
         [0025]      FIG. 2  shows a section A-A through the process chamber  1 . It can be seen that the process chamber is divided into two halves by an intermediate wall  10 . In the one half is located a carrier  11 , which can move into the plane of the drawing and specifically on guidance rollers, of which in  FIG. 2  only two guidance rollers  12 ,  24  are shown. The lower end  13  of carrier  11  in the representation of  FIG. 2  has just decoupled from roller  12  and been moved by means of hooks  14 ,  15  and a (not shown) drive in the direction toward a wall  16 . Behind the feet  2 ,  3  are located lifting pistons, which will be discussed later and which, however, are not evident in  FIG. 1 . Referring back to  FIG. 1 , a gearing  29  is only necessary when utilizing two lifting cylinders in order to make the lifting uniform. A transport beam  17  bears a shaft  18 , which extends through the guidance roller  12  and is connected with one half  19  (or inner component  19 ) of a magnetic coupling, which is located in the process chamber  1 , and is located opposingly with a second half  20  (or outer component  20 ) of the magnetic coupling, which is provided outside of the process chamber  1 . The drive of this second half  20  takes place via a belt drive  21 . In embodiments, the halves  19 ,  20  of the magnetic coupling located opposite to one another have smooth faces capable of gliding past one another. 
         [0026]    Referring to  FIG. 2 , in the left half of process chamber  1  separated by the intermediate wall  10  is shown a further carrier  22  whose movement is such that it egresses from the plane of the drawing. The end  23  of this carrier  22  rests in a guidance roller  24 , through which is guided a shaft  25 , which, in turn, is guided through the component  26  of a magnetic coupling that is located in the process chamber  1 , whose component  27  located outside of process chamber  1 , is driven by a belt drive  28 . 
         [0027]      FIG. 3  shows an enlarged representation of a partial region of  FIG. 2 . Evident is herein again the carrier  11  with its lower end  13 , which now rests in guidance roller  12 . In order for the lower end  13  to be guided out of the roller  12 , a pneumatic cylinder  30  capable of moving a lifting piston  31  upwardly and downwardly is provided. In the position shown in  FIG. 3  the lifting piston  31  is moved upwardly, whereby the transport beam  17  ( FIG. 2 ), the guidance roller  12 , and with it the shaft  18  and the inner component  19  of the magnetic coupling, are also moved upwardly. The inner component  19  of the magnetic coupling is now directly opposite the outer component  20  of the magnetic coupling. A driving shaft  35  supported in a bearing  36  and bearing the outer magnet  20  and driven by the belt drive  21 , is stationarily connected with wall  16 . A thin diaphragm  37  separates the interior of the process chamber  1  from the atmosphere. The diaphragm  37  is fitted into a sleeve  38  or into a portion of this sleeve  38 . 
         [0028]    In the position shown in  FIG. 3 , in which the carrier  11  is moved into the process chamber  1 , the hook  14  is located outside of carrier  11 , i.e., it does not extend into an aperture  40  of the carrier in order to move it in the direction toward the side wall  16  of process chamber  1 . The hook  14  is not fastened on a contact frame  41  but rather on a leadthrough which carries out a horizontal movement. This leadthrough is not visible in  FIG. 3 . 
         [0029]    When the driving shaft  35  is rotated by the belt drive  21 , the outer component  20  of the magnetic coupling located at atmospheric pressure also rotates. Its magnetic field penetrates through the nonmagnetic or nonmagnetizable diaphragm  37  supported in the sleeve  38  or in a portion of this sleeve  38 , and entrains the inner component  19  of the magnetic coupling located in the process chamber  1 . The shaft  18 , and with it the guidance roller  12 , thereby rotate. Since in the guidance roller  12  the lower end of the carrier  11  is supported, the carrier  11  moves into the plane of drawing. 
         [0030]      FIG. 4  shows once again an enlarged representation of a portion of the arrangement depicted in  FIG. 2 , and specifically in the position of  FIG. 2 , in which the carrier  11  is not moved into the plane of drawing, but rather in the direction toward wall  16  of process chamber  1 . In order to reach this position, hook  14 , moved by a drive  45  horizontally toward the left, extends into the aperture  40  of carrier  11 . The lifting cylinder is now lowered such that carrier  11  is suspended in hook  14 . The carrier  11  can now be moved horizontally by means of hook  14 , of a not shown support, and of drive  45 . The two components  19 ,  20  of the magnetic coupling are herein vertically offset with respect to one another. 
         [0031]      FIG. 5  shows a segment from a longitudinal section B-B, with only the right carrier  11  being evident. The longitudinal section of  FIG. 5  extends through a lifting cylinder  60  and a lifting piston  61  connected therewith. A leadthrough  62  is through the bottom  63  of process chamber  1 . Flanged onto the bottom  63  is a holder  64 , in which is located a coupling part  65 , which shows a piston rod  66  of the lifting cylinder  60  with a portion  67  of the lifting piston  61 . The lifting cylinder  60  is a pneumatic cylinder which with the coupling part  65  is screwed into the piston  61 . 
         [0032]    The lifting piston  61  is connected via a support  68  with a transport beam  69  in which a guidance roller  70  can roll. At a spacing from carrier  11  can be seen a prong  71  fastened on a (not shown) support, which is connected with a drive, not shown here, located on the outside of wall  16 . A belt drive  73  drives a magnetic coupling  74 , which, in turn, rotates the guidance roller  70 . 
         [0033]    It is feasible to provide two lifting pistons for each transport beam  69 , one at the front and one at the rear end of the transport beam. It is, however, also possible to provide only one lifting piston which engages in the center of the transport beam  69 . The carrier  11  is pressed out of a contact frame  72  in order to ensure a defined parallel distance between plasma source and substrate. The contact frame serves, in addition, for delimiting the plasma volume and for the grounding of the carrier back electrode.