Patent Publication Number: US-2005142290-A1

Title: Substrate support adapter system

Description:
The present invention relates to a substrate support adapter system, wherein the substrate support or carrier comprises adapters in the form of means for holding and/or gripping the substrate support. The substrate support is configured as a ring which is open in the axial direction, supports at least one substrate and is suitable for treating the substrate on one side or on both sides.  
      The prior art is faced with the problem to handle or treat substrates having different shapes and sizes in one system. In order to overcome this problem, different substrate supports are used which are differently adapted to the holding systems for the substrate supports.  
      It is the object of the present invention to provide a substrate support adapter system which allows substrates having different shapes and sizes to be held and transported in or through a system and which has a variety of applications. This object is achieved with the features of the claims.  
      In achieving the object, the invention starts out from the following basic ideas.  
      The substrate support is configured as a ring enclosing an internal space and comprising on its outer circumference means for engaging with a holding and/or gripping device. The internal space can be freely defined and can accommodate holding devices for different substrates which can be treated on one side or on both sides because the internal space is closed only by the annular or ring-shaped outer wall. The outer wall is defined geometrically and consists of two circumferential concave grooves being arranged symmetrical with respect to the center plane of the ring as well as of a circumferential convex projection whose vertex intersects the center plane of the substrate support ring. The substrate support is held by rollers which either engage with the grooves or are spring-mounted on the projection in combination with a stop. Moreover, the substrate support can be held on the projection by the surfaces of a V-shaped annular groove.  
      The invention provides a uniform connecting point (adapter) to different substrates, which can take over a plurality of functions. In coating processes, the substrate ring protects other machine parts from being coated unintentionally (masking, shielding). In sputter coating processes, the wall of the substrate ring can serve as an anode surface for the process. The wall of the substrate ring can accommodate additional components (e.g., transponders for identifying the support ring or the like. In the internal space of the substrate support ring, the substrate is well protected from damage. In addition to being used in coating processes, the substrate support can also be used in previous and subsequent processes, e.g., for cleaning. In particular, the invention can be used for the treatment of, e.g., CDs, DVDs, optical lenses or lenses of spectacles. 
    
    
      In the following, the invention will be described in more detail on the basis of the drawings in which  
       FIG. 1  is a cross-sectional view of the substrate support according to the present invention,  
       FIG. 2  is a cross-sectional view of the outer wall of the substrate support according to the present invention being engaged with a holding device,  
       FIG. 3  is a cross-sectional view of the outer wall of the substrate support according to the present invention being engaged with two gripping devices, and  
       FIG. 4  is a cross-sectional view of the wall of the substrate support according to the present invention being engaged with a further gripping device. 
    
    
       FIG. 1  shows a cross-sectional view of the substrate support  1  according to the present invention. The substrate support comprises an internal space  2  for receiving at least one substrate  13 . The internal space is surrounded by an annular wall  3  extending vertically with respect to the center plane M of the substrate support. The internal space  2 , which is freely definable, can accommodate means  14  for holding one or more substrates, which are, e.g., spring-mounted on the wall  3 , wherein the substrate  13  (dashed) is preferably arranged symmetrical with respect to the plane M. The holding means  14  are shown only schematically because their shapes have to be adapted to the substrate used.  
      Since the internal space  2  is open on both sides vertically with respect to the center plane M, both one-sided and two-sided treatment processes can be carried out. On the outer circumference  3   a  of the wall  3 , there is a circumferential convex projection  4  which is symmetrical with respect to the center plane M and whose vertex intersects the center plane M. Moreover, two circumferential concave grooves  5   a  and  5   b  are arranged on the one side and the other side of the center plane, i.e. in the drawing above and below the center plane, and symmetrical thereto. The projection  4  and the grooves  5   a  and  5   b  are intended for engaging at least one holding and/or gripping device which either holds the substrate support passively or grips it actively in order to transport the substrate support ring or transfer it to different holding and gripping devices.  
       FIG. 2  shows a substrate support  1  being held in a passive holding device (spring-loaded tension roller)  6 ; a spring  8  presses a roller  7  against the projection  4  (in the drawing) above the center plane M, and a stopping surface  6   a  of the holding device  6  serves as the stop on which the projection  4  rests with its surface  4   a  below the center plane M. The substrate support  1  is introduced by means of pressure into said passive holding device  6  rolling or sliding manner up to the stop on the surface  6   a . The straight stopping surface  4   a  of the projection  4  guarantees a defined height position of the substrate support. The spring-loaded roller holds the substrate support with a defined force. Additionally, the substrate support can be centered if at least three or more holding devices  6  with the spring-loaded tension rollers are arranged on the circumference of the ring. Apart from the holding device  6 , also other positive-locking holding systems, which can be engaged with the structured surface of the wall  3  of the substrate support, can be used.  
       FIG. 3  shows a cross-sectional view of the outer wall  3  of the substrate support adapter system  1  being engaged with first and second gripping devices comprising gripping means  9   a  and  9   b , respectively. The ring means each comprise a gripping finger  11 ; a roller  10  is arranged at the end of the gripping finger  11 ; the rollers  10  are engaged with grooves  5   a  and  5   b  of the substrate support  1 , respectively. The radius of the groove  5   a ,  5   b  is slightly larger than the radius of the roller  10  so that the substrate support  1  is automatically aligned (or self-aligned) vertically with respect to the axis of the roller  10  (the roller  10  heads for the lowermost point of the groove  5   a ,  5   b ). Due to this effect and a centering action, if three or more gripping devices are used, the admissible position tolerance of a gripping system can be relatively large but guarantees at the same time a safe gripping.  
       FIG. 3  shows a case in which an object is from the first gripping device to the second gripping device. The substrate support is still held in the grove  5   a  by the gripping means  9   a  of the first gripping device, while the gripping means  9   b  of the second gripping device has already engaged with the groove  5   b . After removal of the first gripping device (not shown) from the substrate support  1 , the latter can be further transported by the second gripping device.  
       FIG. 4  shows a cross-sectional view of the wall  3  of the substrate support adapter system  1  being engaged with an alternative gripping device consisting two, three or more gripping means having a V-shaped ring groove  12 ; the surface  12   a  of said ring groove  12 , which faces the outer wall, touches the convex projection  4  above and below the center plane M. The ring groove  12  is moved to the projection  4  in the direction of the arrow B. Also in this gripping device the substrate support  1  is automatically aligned or self-aligned vertically with respect to the pressing-on direction B of the ring groove  12 , because the projection  4  slides into the ring groove up to the stop on both sides of the  
      The substrate support adapter system according to the present invention can be used for coating one or more substrates on one or both sides. In particular, the system according to the present invention can be used for coating by means of cathode sputtering, wherein the wall  3  of the substrate support might serve as an anode surface and, for this purpose, preferably consists of a suitable metal or metal alloy.  
      The substrate support adapter system according to the present invention can be used as a uniform and single substrate support adapter system during the entire operating cycle in a system, and it can also be used during other treatment steps required during the process, e.g., cleaning of the substrate.