Patent Publication Number: US-10316425-B2

Title: Substrate holder, plating apparatus, and plating method

Description:
This application claims the priority and benefit of U.S. Provisional Patent Application No. 61/946,630 filed Feb. 28, 2014, the entire content of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a substrate holder used in a plating apparatus which performs a plating process, for example, on a substrate, a plating apparatus having the substrate holder, and a plating method, and particularly relates to a substrate holder which allows power to be supplied to a plurality of types of substrates, a plating apparatus having the substrate holder, and a plating method. 
     BACKGROUND ART 
     It is conventional practice to form a wiring line in a fine wiring groove, a hole, or a resist opening provided in the surface of a semiconductor wafer etc., or to form a bump (protruding electrode), which is electrically connected with a package electrode etc., on the surface of a semiconductor wafer etc. Known methods for forming such wiring lines and bumps include, for example, an electroplating method, a vapor deposition method, a printing method, and a ball bump method. Due to increase in the number of I/Os and the reduction in pitch of semiconductor chips in the recent years, the electroplating method which allows for miniaturization and relatively stable performance has been widely used. 
     A plating apparatus used for the electroplating method is equipped with a substrate holder which holds a substrate such as a semiconductor wafer with an edge surface and the back surface of the substrate being sealed and the surface (surface to be plated) being exposed. When a plating process of the substrate surface is performed in this plating apparatus, the substrate holder holding the substrate is immersed in a plating solution. 
     Here, when a plating process is performed on the substrate held by the substrate holder, the substrate needs to be electrically connected with the negative voltage side of a power source to apply a negative voltage to the substrate surface. For this purpose, the substrate holder is provided with an electrical contact for electrically connecting an external wiring line extending from the power source and the substrate with each other. The electrical contact is configured to contact with a seed layer (conductive layer) formed on the surface of the substrate to thereby apply a negative voltage to the substrate. 
     Here, depending on the type of substrate, the substrate to be plated can vary in contact position of the electrical contact. For example, in the case of a substrate for forming a bump or a redistribution layer in which a resist pattern is formed on the surface to be plated, it is necessary to bring the electrical contact into contact with the outer peripheral end of the substrate where no resist pattern is formed. Due to the requirement for producing many chips from one substrate, it has become common to bring the electrical contact and the seal into contact with the substrate further on the outer side. On the other hand, a substrate with a TSV (Through Silicon Via) formed in it is composed of a support substrate and an active wafer bonded to the support substrate, and the surface of the active wafer is the surface to be plated. It is therefore necessary that the electrical contact comes into contact with the active wafer. The diameter of this active wafer is smaller than the diameter of the support substrate. Accordingly, the contact position of the electrical contact on the active wafer surface should be located further on the inside in the radial direction than the contact position of the electrical contact on the substrate for forming a bump or a rewiring line. 
     In order to form a plating film of a constant thickness on a substrate, it is necessary to reliably bring the electrical contact into contact with the seed layer and apply a plating current. For this purpose, a substrate holder provided with an electrical contact for exclusive use with each different type of substrate is designed and loaded on a plating apparatus. 
     CITATION LIST 
     Patent Literature 
     [Patent Literature 1] Japanese Patent Laid-Open No. 5-222590 
     However, when a plating process of a plurality of types of substrates is performed by using one plating apparatus, it is necessary to load a plurality of types of substrate holders corresponding to the types of substrates in order to achieve a desired throughput. This causes an increase in the number of the substrate holders, so that the occupation area of a stocker for storing the substrate holders inside the plating apparatus increases, which unfortunately results in an increase in installation area of the plating apparatus. Another problem is that due to the necessity of automatically or manually selecting a substrate holder to be used according to the type of substrate, the operation and manipulation of the apparatus is complicated. 
     The present invention has been devised in view of the above-described problems, and one object of the present invention is to provide a substrate holder which allows power to be supplied to a plurality of types of substrates, a plating apparatus equipped with the substrate holder, and a plating method. 
     SUMMARY 
     A substrate holder according to one form of the present invention is a substrate holder for holding a substrate, and includes a substrate holding surface for holding the substrate and a first power supply member and a second power supply member which allow power to be supplied to substrates having different properties, wherein: the first power supply member has a first power supply member end part which extends toward the inside of the substrate holding surface and is disposed at a first position of the substrate holding surface; the second power supply member has a second power supply member end part which extends toward the inside of the substrate holding surface and is disposed at a second position of the substrate holding surface; and the first position is located on the center side of the substrate holding surface relative to the second position. 
     According to the present invention, it is possible to provide a substrate holder which allows power to be supplied to a plurality of types of substrates and a plating apparatus equipped with this substrate holder. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an overall arrangement plan of a plating apparatus equipped with a substrate holder according to one embodiment; 
         FIG. 2  is a perspective view of the substrate holder according to the embodiment; 
         FIG. 3A  is a cross-sectional view showing a conductor and an electrical contact of the substrate holder before holding a substrate; 
         FIG. 3B  is a cross-sectional view showing the conductor and the electrical contact of the substrate holder after holding the substrate; 
         FIG. 4  is an exploded perspective view of the electrical contact; 
         FIG. 5  is a perspective view of the electrical contact; 
         FIG. 6  is a top view of the electrical contact; 
         FIG. 7  is a front view of the electrical contact; 
         FIG. 8  is an enlarged side view of the part A shown in  FIG. 4 ; 
         FIG. 9  is a schematic view showing another embodiment of a first electrical contact and a second electrical contact; 
         FIG. 10  is a schematic cross-sectional view of a substrate with a TSV formed in it and the electrical contact in contact with this substrate; 
         FIG. 11A  is a schematic cross-sectional view of a substrate for forming a bump or a rewiring line and an electrical contact in contact with this substrate; 
         FIG. 11B  is a schematic cross-sectional view showing another example of the substrate W for forming a bump or a rewiring line and the electrical contact in contact with this substrate W; 
         FIG. 11C  is a schematic cross-sectional view showing another example of the substrate W for forming a bump or a rewiring line and the electrical contact in contact with this substrate W; 
         FIG. 12A  is a side view of an electrical contact according to another embodiment; 
         FIG. 12B  is a front view of the electrical contact according to the another embodiment; 
         FIG. 12C  is a top view of the electrical contact according to the another embodiment; 
         FIG. 13A  is a side view of an electrical contact according to another embodiment; 
         FIG. 13B  is a perspective view of an electrical contact end part according to the another embodiment; 
         FIG. 14  is a side view of an electrical contact according to another embodiment; 
         FIG. 15A  is a side view of an electrical contact according to another embodiment; and 
         FIG. 15B  is a front view of the electrical contact according to the another embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     According to a first form of an embodiment of the present invention, a substrate holder for holding a substrate is provided. This substrate holder comprises a substrate holding surface for holding the substrate and a first power supply member and a second power supply member configured to allow power to be supplied to substrates having different properties. The first power supply member comprises a first power supply member end part which extends toward the inside of the substrate holding surface and is disposed at a first position of the substrate holding surface, while the second power supply member comprises a second power supply member end part which extends toward the inside of the substrate holding surface and is disposed at a second position of the substrate holding surface, and the first position is located on the center side of the substrate holding surface relative to the second position. 
     According to the first form, since the position at which the first power supply member end part is disposed is located further on the center side of the substrate holding surface than the position at which the second power supply member end part is disposed, it is possible to supply power to substrates having different properties (a plurality of types of substrates). As there is no need to prepare a plurality of types of substrate holders corresponding to substrates having different properties, it is possible to avoid an increase in occupation area of the stocker for storing the substrate holders in the plating apparatus. Moreover, as there is no need to prepare a plurality of types of substrate holders, it is possible to prevent complication of the process control due to handling of a plurality of types of substrate holders. 
     According to a second form of this embodiment, in the substrate holder of the first form, the first power supply member is configured to be separable from the second power supply member. 
     According to the second form, when either the first power supply member end part or the second power supply member end part has worn, only the one that has worn can be replaced. Therefore, the cost can be reduced compared with the case where the first power supply member end part and the second power supply member end part are configured integrally and need to be replaced integrally. 
     According to a third form of the embodiment, in the substrate holder of the first form, at least one first power supply member end part and at least one second power supply member end part are disposed adjacent to each other alternately along the circumferential direction of the substrate. 
     According to the third form, it is possible to prevent the first power supply member end part or the second power supply member end part from unevenly coming into contact with the substrate, and to uniformize the distribution of current flowing through the substrate. Therefore, when a substrate is plated using the substrate holder of the third form, it is possible to make the thickness and the quality of the film formed on the substrate more uniform. 
     According to a fourth form of the embodiment, in the substrate holder of the first form, the first power supply member end part and/or the second power supply member end part comprises a protruding portion which comes into contact with the substrate. 
     According to the fourth form, it is possible to supply power stably to the substrate as the protruding portion comes into contact with a predetermined part of the substrate. 
     According to a fifth form of the embodiment, a substrate holder for holding a substrate is provided. This substrate holder comprises a power supply member configured to contact with the substrate, and the power supply member comprises a first power supply member end part configured to contact with the substrate at a first position and a second power supply member end part configured to contact with the substrate at a second position further outside in the radial direction than the first position of the substrate, and the first power supply member end part is configured to be separable from the second power supply member end part. 
     According to the fifth form, the first power supply member end part is configured to contact with the substrate at the first position, while the second power supply member end part is configured to contact with the substrate at the second position. Thus, either the first power supply member end part or the second power supply member end part comes into contact with substrates having different properties (a plurality of types of substrates) and allows power to be supplied to the substrates. As a result, there is no need to prepare a plurality of types of substrate holders corresponding to substrates having different properties, and it is possible to avoid an increase in occupation area of the stocker for storing the substrate holders inside the plating apparatus. Moreover, as there is no need to prepare a plurality of types of substrate holders, it is possible to prevent complication of the process control due to handling of a plurality of types of substrate holders. In addition, according to the fifth form, when either the first power supply member end part or the second power supply member end part has worn, only the one that has worn can be replaced. Therefore, the cost can be reduced compared with the case where the first power supply member end part and the second power supply member end part are configured integrally and need to be replaced integrally. 
     According to a sixth form of the embodiment, a plating apparatus is provided. This plating apparatus comprises the substrate holder of the first form. 
     According to a seventh form of the embodiment, a plating method is provided which includes: disposing a substrate holder, which holds a first substrate or a second substrate having properties different from those of the first substrate, and an anode to face each other in a plating solution; and applying a voltage to the first substrate or the second substrate and the anode. In this plating method, the substrate holder comprises a power supply member configured to contact with the first substrate and the second substrate, and the power supply member comprises a first power supply member end part configured to contact with a front plane surface portion of the first substrate and a second power supply member end part configured to contact with a front bevel portion or a front shoulder portion of the second substrate. 
     According to the seventh form, the first power supply member end part can come into contact with the front plane surface portion of the first substrate, while the second power supply member end part can come into contact with the front bevel portion or the front shoulder portion of the second substrate. Thus, at least either the first power supply member end part or the second power supply member end part comes into contact with substrates having different properties (a plurality of types of substrates) and allows power to be supplied to the substrates for plating. As a result, there is no need to prepare a plurality of types of substrate holders corresponding to substrates having different properties, and it is possible to avoid an increase in occupation area of the stocker for storing the substrate holders inside the plating apparatus. Moreover, as there is no need to prepare a plurality of types of substrate holders, it is possible to prevent complication of the operation of the device due to handling of a plurality of types of substrate holders. 
     According to an eighth form of the embodiment, in the plating method of the seventh form, the first substrate is a bonded substrate and the second substrate is a substrate for forming a bump or a rewiring line. 
     According to the eighth form, the first power supply member end part comes into contact with the front plane surface portion of the bonded substrate, and the second power supply member end part comes into contact with the front bevel portion or the front shoulder portion of the substrate for forming a bump or a rewiring line. Thus, the substrate holder of this form allows power to be supplied to the substrates having different properties, namely, the bonded substrate and the substrate for forming a bump or a rewiring line, for plating. 
     According to a ninth form of the embodiment, in the plating method of the seventh form, the first substrate is a bonded substrate and the second substrate is a substrate with a resist having an opening formed on the surface. 
     According to the ninth form, the first power supply member end part comes into contact with the front plane surface portion of the bonded substrate, and the second power supply member end part comes into contact with the front bevel portion or the front shoulder portion of the substrate with the resist having the opening formed on the surface. Thus, the substrate holder of this form allows power to be supplied to the substrates having different properties, namely, the bonded substrate and the substrate with a bump or a resist having an opening formed on the surface, for plating. 
     According to a tenth form of the embodiment, in the plating method of the seventh form, the second power supply member end part is configured to contact with the front plane surface portion of the first substrate. 
     According to the tenth form, the second power supply member end part can also come into contact with the front plane surface portion of the first substrate. Therefore, when the first substrate is held by this substrate holder, the first power supply member end part and the second power supply member end part come into contact with the front plane surface portion of the first substrate. Thus, as the number of contacts for supplying power to the first substrate increases, the current supply to the substrate becomes uniform and the in-plane uniformity of the film can be improved. 
     According to an eleventh form of the embodiment, in the plating method of the seventh form, at least one first power supply member end part and at least one second power supply member end part are disposed adjacent to each other alternately along the circumferential direction of the first substrate or the second substrate. 
     According to the eleventh form, it is possible to prevent the first power supply member end part or the second power supply member end part from unevenly coming into contact with the substrate, and to uniformize the distribution of current flowing through the substrate. Thus, when a substrate is plated by the plating method of the eleventh form, it is possible to make the thickness and the quality of the film formed on the substrate more uniform. 
     According to a twelfth form of the embodiment, in the plating method of the seventh form, the first power supply member end part is configured to be separable from the second power supply member end part. 
     According to the twelfth form, when either the first power supply member end part or the second power supply member end part has worn, only the one that has worn can be replaced. Therefore, the cost can be reduced compared with the case where the first power supply member end part and the second power supply member end part are configured integrally and need to be replaced integrally. 
     According to a thirteenth form of the embodiment, in the plating method of the seventh form, the first power supply member end part and/or the second power supply member end part comprises a protruding portion which comes into contact with the substrate. 
     According to the thirteenth form, it is possible to supply power stably to the substrate as the protruding portion comes into contact with a predetermined part of the substrate. 
     In the following, more detailed embodiments will be described with reference to the drawings. In the drawings to be described below, the same or equivalent components will be denoted by the same reference signs and a repeated description thereof will be omitted. 
       FIG. 1  is an overall arrangement plan of a plating apparatus equipped with a substrate holder according to one embodiment. As shown in  FIG. 1 , this plating apparatus  1  is equipped with two cassette tables  12  on which cassettes  10  storing substrates such as semiconductor wafers are loaded, an aligner  14  which orients the positions of an orientation flat, a notch, etc. of a substrate to a predetermined direction, a substrate mounting/dismounting part  20  which mounts or dismounts a substrate on/from a substrate holder  18  loaded on the a substrate mounting/dismounting part  20 , and a spin dryer  16  which dries plated substrates through high-speed rotation. At roughly the center of these units, a substrate carrier device  22  which is, for example, a carrier robot for carrying a substrate among these units is disposed. 
     The substrate mounting/dismounting part  20  includes a flat loading plate  52  which can be slid in the horizontal direction along rails  50 . In a state where two substrate holders  18  are loaded horizontally side by side on the loading plate  52 , the substrate carrier device  22  delivers or receives a substrate to or from one of the substrate holders  18 . Thereafter, the substrate carrier device  22  slides the loading plate  52  in the horizontal direction and delivers or receives a substrate to or from the other substrate holder  18 . 
     In the plating apparatus  1 , there are further disposed a stocker  24  for storing and temporarily placing the substrate holders  18 , a pre-wet tank  26  for immersing the substrate in pure water, a pre-soak tank  28  for removing by etching an oxide film from the surface of the seed layer formed on the surface of the substrate, a first water washing tank  30   a  for washing the surface of the substrate with pure water, a blow tank  32  for draining the washed substrate, a second water washing tank  30   b , and a plating tank  34 . 
     The plating tank  34  includes an overflow tank  36  and a plurality of copper plating units  38  housed inside the overflow tank  36 . Each copper plating unit  38  houses the substrate holder  18  holding a substrate inside the copper plating unit  38 , and performs a plating process such as copper plating on the substrate. While copper plating will be described in this example, the same plating apparatus  1  can be used for plating with nickel, solder, silver, gold, etc. as well. 
     The plating apparatus  1  is further equipped with a substrate holder carrier device  40  which carries the substrate holder  18  along with a substrate. For example, the substrate holder carrier device  40  is a linear motor system, and is located on one side of the substrate mounting/dismounting part  20  and the tanks. The substrate holder carrier device  40  has a first transporter  42  which carries a substrate between the substrate mounting/dismounting part  20  and the stocker  24 , and a second transporter  44  which carries a substrate among the stocker  24 , the pre-wet tank  26 , the pre-soak tank  28 , the water washing tanks  30   a ,  30   b , the blow tank  32 , and the plating tank  34 . However, the substrate holder carrier device  40  may be equipped with only the first transporter  42  without the second transporter  44 . 
     A paddle driving device  46  which drives a paddle (not shown) located inside each copper plating unit  38  and agitating a plating solution is disposed on one side of the overflow tank  36 . 
       FIG. 2  is a perspective view of the substrate holder  18  according to the embodiment used in the plating apparatus  1  shown in  FIG. 1 . As shown in  FIG. 2 , the substrate holder  18  has a first holding member  54  which is, for example, made of vinyl chloride and has a rectangular flat plate-like shape, and a second holding member  58  which is mounted through a hinge  56  on this first holding member  54  to be opened or closed. At roughly the center of the first holding member  54  of the substrate holder  18 , a holding surface  80  for holding a substrate (corresponding to one example of the substrate holding surface) is provided. On the outside of the holding surface  80  of the first holding member  54 , inverted L-shaped clampers  74  having a projecting portion projecting inward are provided at regular intervals along the circumference of the holding surface  80 . 
     A pair of substantially T-shaped hands  82 , which serves as a support when the substrate holder  18  is carried or suspended and supported, is coupled at the end of the first holding member  54  of the substrate holder  18 . Inside the stocker  24  shown in  FIG. 1 , the substrate holder  18  is suspended and supported vertically by hanging the hands  82  on the upper surface of the peripheral wall of the stocker  24 . This substrate holder  18  suspended and supported is carried by gripping the hands  82  of the substrate holder  18  with the first transporter  42  or the second transporter  44  of the substrate holder carrier device  40 . Also inside the pre-wet tank  26 , the pre-soak tank  28 , the water washing tanks  30   a ,  30   b , the blow tank  32 , and the plating tank  34 , the substrate holder  18  is suspended and supported on the peripheral wall through the hands  82 . 
     The hand  82  is provided with external contacts (not shown) to be connected with an external power supply unit. These external contacts are electrically connected through a plurality of wiring lines with a plurality of conductors  88  (see  FIG. 3 ) provided on the outer periphery of the holding surface  80 . 
     The second holding member  58  includes a base part  61  fixed on the hinge  56  and a ring-shaped seal holder  62  fixed on the base part  61 . A presser ring  64  for pressing and fixing the seal holder  62  on the first holding member  54  is rotatably mounted on the seal holder  62  of the second holding member  58 . The presser ring  64  has a plurality of ridges  64   a  projecting outward from the outer periphery. The upper surface of the ridges  64   a  and the lower surfaces of the inward projecting portions of the clampers  74  have tapered surfaces inclined in opposite directions from each other along a rotation direction. 
     To hold a substrate, first, the substrate is loaded on the holding surface  80  of the first holding member  54  with the second holding member  58  opened, and the second holding member  58  is closed through the hinge  56 . Next, the presser ring  64  is rotated clockwise to slide the ridges  64   a  of the presser ring  64  to the inside (lower side) of the inward projecting portions of the clampers  74 . The first holding member  54  and the second holding member  58  are thereby fastened and locked with each other through the tapered surfaces provided in each of the presser ring  64  and the clamper  74 , so that the substrate is held. To release the substrate from the holding, the presser ring  64  is rotated counterclockwise with the first holding member  54  and the second holding member  58  locked with each other. The ridges  64   a  of the presser ring  64  are thereby disengaged from the inverted L-shaped clampers  74 , so that the substrate is released from the holding. 
       FIG. 3  is a cross-sectional view showing the conductor and the electrical contact of the substrate holder  18  shown in  FIG. 2 ;  FIG. 3A  shows a state before holding a substrate and  FIG. 3B  shows a state after holding the substrate. As shown in  FIG. 3A , a substrate W is supported on the holding surface  80  of the first holding member  54 , and the plurality of conductors  88  (one is shown) which are connected with the plurality of wiring lines extending from the external contacts provided in the hand  82  are disposed between the holding surface  80  and the first holding member  54 . The plurality of conductors  88  are disposed on the outside of the circumference of the substrate W so that, when the substrate W is loaded on the holding surface  80  of the first holding member  54 , the ends of these conductors  88  are exposed while keeping a spring property on the surface of the first holding member  54  on the side of the substrate W. 
     A seal member  60 , with which the outer periphery of the surface of the substrate W and the first holding member  54  come into pressure contact when the substrate W is held by the substrate holder  18 , is mounted on the surface (lower surface in the drawing) of the seal holder  62  facing the first holding member  54 . The seal member  60  has a lip portion  60   a  for sealing the surface of the substrate W and a lip portion  60   b  for sealing the surface of the first holding member  54 . 
     A support  90  is mounted on the inside of the seal member  60  between the pair of lip portions  60   a ,  60   b . A plurality of electrical contacts  92  (power supply members) to which power can be supplied from the conductors  88  are fixed, for example, with a screw on the support  90 , and disposed along the circumference of the substrate W. 
     The electrical contact  92  has a first electrical contact end part  93   a  (corresponding to one example of the first power supply member end part) extending toward the inside of the holding surface  80  and a second electrical contact end part  94   a  (corresponding to one example of the second power supply member end part) extending toward the inside of the holding surface  80 . A portion of the first electrical contact end part  93   a  which comes into contact with the substrate is disposed on or above a first position of the holding surface  80 . A portion of the second electrical contact end part  93   b  which comes into contact with the substrate is disposed on or above a second position of the holding surface  80 . The first position of the holding surface  80  is located on the center side of the holding surface  80  relative to the second position of the holding surface  80 . Thus, the first electrical contact end part  93   a  comes into contact with the substrate W at an inner position in the radial direction (corresponding to one example of the first position), while the second electrical contact end part  94   a  comes into contact with the substrate W loaded on the holding surface  80  at an outer position in the radial direction (corresponding to one example of the second position). 
     The first electrical contact end part  93   a  and the second electrical contact end part  94   a  of this electrical contact  92  are formed to project in the shape of a flat spring in the central direction of the substrate W. The electrical contact  92  has leg portions  93   b ,  94   b , to which power can be supplied from the conductors  88 , at positions (on the lower surface in the drawing) of the support  90  facing the conductors  88 . 
     When the first holding member  54  and the second holding member  58  shown in  FIG. 2  are locked with each other, the short lip portion  60   a  on the inner peripheral surface side of the seal member  60  and the longer lip portion  60   b  on the outer peripheral surface side are pressed against the surface of the substrate W and the surface of the first holding member  54 , respectively, as shown in  FIG. 3B . The gap between the lip portion  60   a  and the lip portion  60   b  is thereby reliably sealed and the substrate W is held. 
     In a region sealed by the seal member  60 , namely, the region between the pair of lip portions  60   a ,  60   b  of the seal member  60 , the conductors  88  are electrically connected with the leg portions  93   b ,  94   b  of the electrical contact  92 , and at the same time the first electrical contact end part  93   a  and the second electrical contact end part  94   a  come into contact with the substrate W. Thus, it is possible to supply power to the substrate W through the electrical contact  92  while sealing the substrate W with the seal member  60  and holding the substrate W in the substrate holder  18 . 
     Next, the electrical contact  92  shown in  FIG. 3A  and  FIG. 3B  will be described in detail.  FIG. 4  is an exploded perspective view of the electrical contact  92 ,  FIG. 5  is a perspective view of the electrical contact  92 ,  FIG. 6  is a top view of the electrical contact  92 ,  FIG. 7  is a front view of the electrical contact  92 , and  FIG. 8  is an enlarged side view of the part A shown in  FIG. 5 . 
     As shown in  FIG. 4 , the electrical contact  92  has the first electrical contact  93  (corresponding to one example of the first power supply member) and the second electrical contact  94  (corresponding to one example of the second power supply member). The first electrical contact  93  has the plurality of first electrical contact end parts  93   a , a substantially plate-like first electrical contact body  93   c  for connecting these plurality of first electrical contact end parts  93   a  with one another, and the first leg portion  93   b  which is formed in a lower part of the first electrical contact body  93   c  and electrically connected with the conductors  88  (see  FIG. 3A  and  FIG. 3B ). 
     Similarly, the second electrical contact  94  has the plurality of second electrical contact end parts  94   a , a substantially plate-like second electrical contact body  94   c  for connecting these second electrical contact end parts  94   a  with one another, and a second leg portion  94   b  which is formed in a lower part of the second electrical contact body  94   c  and electrically connected with the conductors  88  (see  FIG. 3A  and  FIG. 3B ). 
     The plurality of first electrical contact end parts  93   a  are disposed to have a predetermined interval with one another and formed integrally with the first electrical contact body  93   c . The plurality of second electrical contact end parts  94   a  are disposed to have a predetermined interval with one another and formed integrally with the second electrical contact body  94   c . The first electrical contact body  93   c  and the second electrical contact body  94   c  are provided with a plurality of holes  93   d ,  94   d  for fixing these electrical contact bodies with screws etc. on the support  90  shown in  FIG. 3A  and  FIG. 3B . 
     To fix the electrical contact  92  on the support  90  shown in  FIG. 3A  and  FIG. 3B , first, the second electrical contact  94  is placed against the back surface side of the first electrical contact  93  as indicated by the dashed arrows in  FIG. 4 . In the state where the first electrical contact  93  and the second electrical contact  94  shown in  FIG. 5  through  FIG. 7  are placed against each other, the electrical contact  92  is fixed on the support  90  shown in  FIG. 3A  and  FIG. 3B . The first electrical contact  93  and the second electrical contact  94  are configured so that, when the first electrical contact body  93   c  and the second electrical contact body  94   c  are placed against each other with the holes  93   d  and the holes  94   d  coinciding with each other, the first electrical contact end parts  93   a  and the second electrical contact end parts  94   a  are disposed alternately. When the electrical contact  92  is fixed on the support  90  shown in  FIG. 3 , the first electrical contact end parts  93   a  and the second electrical contact end parts  94   a  are disposed adjacent to each other alternately along the circumferential direction of the substrate. 
     As shown in  FIG. 4  through  FIG. 8 , the first electrical contact end part  93   a  extends from the first electrical contact body  93   c  and is curved substantially at a right angle to the first electrical contact body  93   c . As shown in  FIG. 8 , a bent-up portion  93   e  (corresponding to one example of the protruding portion) which is bent up at a predetermined angle is provided at the tip of the first electrical contact end part  93   a . As will be described later, this bent-up portion  93   e  is a contact part which comes into contact with the substrate W. 
     Similarly, the second electrical contact end part  94   a  extends from the second electrical contact body  94   c  and is curved substantially at a right angle to the second electrical contact body  94   c . A bent-up portion  94   e  (corresponding to one example of the protruding portion) which is bent up at a predetermined angle is provided at the tip of the second electrical contact end part  94   a . As will be described later, this bent-up portion  94   e  is a contact part which comes into contact with the substrate W. Here, the bent-up portion  94   e  of the second electrical contact end part  94   a  is formed closer to the electrical contact body  93   c ,  94   c  than the bent-up portion  93   e  of the first electrical contact end part  93   a . Accordingly, as has been described with  FIGS. 3A and 3B , the first electrical contact end part  93   a  comes into contact with the substrate W at an inner position in the radial direction, while the second electrical contact end part  94   a  comes into contact with the substrate W loaded on the holding surface  80  at an outer position in the radial direction. 
     In this embodiment, the first electrical contact  93  and the second electrical contact  94  are separable from each other, and therefore the first electrical contact end part  93   a  and the second electrical contact end part  94   a  are separable from each other. That is, the first electrical contact end part  93   a  and the second electrical contact end part  94   a  are configured as separate members. However, the first electrical contact end part  93   a  and the second electrical contact end part  94   a  may be formed integrally by sharing the electrical contact body and the conductors. 
     Since the electrical contact  92  used for the substrate holder  18  is a consumable, it needs to be replaced after a predetermined period of use. If the first electrical contact end part  93   a  and the second electrical contact end part  94   a  are separable from each other as in this embodiment, when either the first electrical contact end part  93   a  or the second electrical contact end part  94   a  has worn, only the electrical contact that has worn can be replaced. Therefore, the cost can be reduced compared with the case where the first electrical contact end part  93   a  and the second electrical contact end part  94   a  are configured integrally and need to be replaced integrally. 
       FIG. 9  is a schematic view showing another embodiment of the first electrical contact  93  and the second electrical contact  94 . The first electrical contact  93  and the second electrical contact  94  shown in  FIG. 4  through  FIG. 8  are configured so that one first electrical contact end part  93   a  and one second electrical contact end part  94   a  are disposed alternately and adjacent to each other. However, as in the embodiment shown in  FIG. 9 , a set of first electrical contact end parts  93   a , formed of a plurality of first electrical contact end parts  93   a  adjacent to one another, and a set of second electrical contact end parts  94   a , formed of a plurality of second electrical contact end parts  94   a  adjacent to one another, may be disposed adjacent to each other alternately along the circumferential direction of the substrate. Thus, as the first electrical contact end parts  93   a  and the second electrical contact end parts  94   a  are alternately disposed adjacent to each other, it is possible to prevent the first electrical contact end part  93   a  or the second electrical contact end part  94   a  from unevenly coming into contact with the substrate, and to uniformize the distribution of current flowing through the substrate. Therefore, when a substrate is plated using this substrate holder, it is possible to make the thickness and the quality of the film formed on the substrate more uniform. 
     Although the first electrical contact body  93   c  and the second electrical contact body  94   c  shown in  FIG. 4  through  FIG. 9  have a flat plate shape, the first electrical contact body  93   c  and the second electrical contact body  94   c  are curved along the circumferential direction of the substrate when mounted on the support  90  shown in  FIG. 3A  and  FIG. 3B . Accordingly, the first electrical contact end parts  93   a  and the second electrical contact end parts  94   a  are disposed along the circumferential direction of the substrate. 
       FIG. 10  is a schematic cross-sectional view of the substrate W with a TSV formed in it and the electrical contact  92  which comes into contact with this substrate W. In the example shown in  FIG. 10 , a bonded substrate W composed of a support substrate W 1  and an active wafer W 2  bonded on the support substrate W 1  is the substrate W to be held by the substrate holder  18  according to this embodiment. In this bonded substrate W, for example, a TSV is formed in the active wafer W 2 , and the surface of the active wafer W 2  is the surface to be plated. Therefore, a seed layer  104  being a conductive layer is formed on the surface of the active wafer W 2 . It is often the case with such a bonded substrate W that due to the manufacturing process the diameter of the active wafer W 2  is smaller than the diameter of the support substrate W 1 , while the support substrate W 1  is manufactured in the size of a common substrate. 
     Here, the first electrical contact end part  93   a  (bent-up portion  93   e ) of the electrical contact  92  comes into contact with the active wafer W 2  at a position (first position P 1 ) on a front plane surface portion  101  to supply power to the seed layer  104  of the active wafer W 2 . 
     The second electrical contact end part  94   a  (bent-up portion  94   e ) of the electrical contact  92  comes into contact with the active wafer W 2  at a position (second position P 2 ) further outside in the radial direction than the first position P 1  to supply power to the seed layer  104  of the active wafer W 2 . 
     When the first electrical contact end part  93   a  and the second electrical contact end part  94   a  both can supply power to the seed layer  104  of the active wafer W 2  as in the example shown in  FIG. 10 , as the electrical contact  92  comes into contact with the active wafer W 2  more evenly along the circumference, the current supply to the seed layer  104  becomes uniform and the in-plane uniformity can be improved. 
     In the example shown in  FIG. 10 , not only the first electrical contact end part  93   a  but also the second electrical contact end part  94   a  supplies power to the active wafer W 2 . However, as long as at least the first electrical contact end part  93   a  can supply power to the active wafer W 2 , it is not absolutely necessary that the second electrical contact end part  94   a  comes into contact with the seed layer  104  of the active wafer W 2 . That is, since the first electrical contact end part  93   a  comes into contact with the substrate W at a position further on the inside in the radial direction than the second electrical contact end part  94   a , even when the second electrical contact end part  94   a  does not come into contact with the seed layer  104  of the active wafer W 2 , the first electrical contact end part  93   a  can come into contact with the seed layer  104  to supply power to the active wafer W 2 . 
     In the case where the second electrical contact end part  94   a  does not come into contact with the seed layer  104  of the active wafer W 2 , it is desirable that the tip of the second electrical contact end part  94   a  is long enough to be salient to the inside from the outer peripheral end of the active wafer W 2 . If the tip of the second electrical contact end part  94   a  lies closer to the outer side than the outer peripheral end of the active wafer W 2 , the tip may catch on the outer peripheral end of the active wafer W 2 , so that chipping or cracking of the active wafer W 2  occurs or the substrate holder  18  cannot be removed with the bonded substrate W held in it. 
       FIG. 11A  is a schematic cross-sectional view of the substrate W for forming a bump or a redistribution layer and the electrical contact  92  which comes into contact with this substrate W. In the example shown in  FIG. 11A , the substrate W in which a bump or a rewiring line is formed is the substrate to be held by the substrate holder  18  according to this embodiment. This substrate W for forming a bump or a rewiring line has a front plane surface portion  101 , a front bevel portion  102 , and a front shoulder portion  103 . The names of portions of a substrate are based on the definition of SEMI M73-0309. 
     The substrate W for forming a bump or a rewiring line has the seed layer  104  formed over the front plane surface portion  101 , the front bevel portion  102 , and the front shoulder portion  103 , and a resist  105  is formed on the seed layer  104  of the front plane surface portion  101 . The substrate W for forming a bump or a rewiring line refers to a substrate in which an opening is provided in the resist  105  formed on the seed layer  104  and the inside of the opening is plated to form a bump (protruding electrode) or a rewiring line. 
     Here, the first electrical contact end part  93   a  (bent-up portion  93   e ) of the electrical contact  92  is in contact with the substrate W for forming a bump or a rewiring line at a position (first position P 1 ) on the front plane surface portion  101 . Since the resist  105  is formed on the front plane surface portion  101  of the substrate W for forming a bump or a rewiring line, the first electrical contact end part  93   a  does not supply power to the seed layer  104 . 
     On the other hand, the second electrical contact end part  94   a  (bent-up portion  94   e ) of the electrical contact  92  is in contact with the substrate W for forming a bump or a rewiring line at a position (second position P 2 ) on the front bevel portion  102  or the front shoulder portion  103 . Since the resist  105  is not formed on the front bevel portion  102  and the front shoulder portion  103  of the substrate W for forming a bump or a rewiring line, the second electrical contact end part  94   a  can supply power to the seed layer  104 . 
     Thus, when the substrate holder  18  holds the substrate W for forming a bump or a rewiring line, the first electrical contact end part  93   a  does not supply power to the substrate W for forming a bump or a rewiring line, while the second electrical contact end part  94   a  can come into contact with the substrate W at the second position P 2  on the front bevel portion  102  or the front shoulder portion  103  and supply power. 
     In  FIG. 11A , the bent-up portion  94   e  of the second electrical contact end part  94   a  is in contact with the substrate W at a position on the front bevel portion  102  or the front shoulder portion  103 . However, a flat portion other than the bent-up portion  94   e  of the first electrical contact end part  93   a  may come into contact with the front shoulder portion  103 , for example. Alternatively, the second electrical contact end part  94   a  may be smoothly curved without having the specific bent-up portion  94   e.    
     As shown in  FIG. 11B , when the seed layer  104  of the substrate W for forming a bump or a rewiring line is also formed in an apex portion  106 , the second electrical contact end part  94   a  may come into contact with the substrate W at the second position P 2  on the apex portion  106  to supply power. As shown in  FIG. 11C , when the seed layer  104  is also formed in a back shoulder portion  107  and a back bevel portion  108  of the substrate W for forming a bump or a rewiring line, the second electrical contact end part  94   a  may come into contact with the substrate W at the second position P 2  of the seed layer on the back shoulder portion  107  or the back bevel portion  108  to supply power. Although not shown, when the seed layer  104  is also formed in a back surface portion  109 , the second electrical contact end part  94   a  may come into contact with the seed layer on the back surface portion  109  of the substrate to supply power. 
     As has been described, since the substrate holder  18  according to this embodiment has the first electrical contact end part  93   a , which can come into contact with the bonded substrate W at the first position P 1  on the front plane surface portion  101 , and the second electrical contact end part  94   a , which can come into contact with the substrate W for forming a bump or a rewiring line at the second position P 2  on the front bevel portion  102  or the front shoulder portion  103 , it is possible to supply power to substrates through at least either the first electrical contact end part  93   a  or the second electrical contact end part  94   a  even when the substrates have different properties. 
     Here, the different properties of substrates are of course not limited to the difference between the bonded substrate W and the substrate W for forming a bump or a rewiring line. For example, some substrates for forming a bump or a rewiring line have no seed layer formed on the front bevel portion  102  or the front shoulder portion  103 , unlike the substrate W for forming a bump or a rewiring line shown in  FIG. 11A  through  FIG. 11C . For such substrates, power is supplied from the seed layer formed on the front plane surface portion  101 . That is, there can be different types of substrates even among the substrates for forming a bump or a rewiring line; one type is a substrate to which power is supplied by bringing the contact into contact with the front plane surface portion  101 , while the other type is a substrate to which power is supplied by bringing the contact into contact with the front bevel portion  102  or the front shoulder portion  103 . 
     The first position and the second position at which the first power supply member end part and the second power supply end part which allow power to be supplied to substrates having different properties respectively come into contact with the substrate can be selected from different positions of the front plane surface portion, front bevel portion, front shoulder portion, apex portion, back shoulder portion, back bevel portion, and back surface portion. 
     Since the substrate holder  18  according to this embodiment allows power to be supplied to substrates having different properties such as the bonded substrate W and the substrate W for forming a bump or a rewiring line, it is possible to avoid an increase in the number of substrate holders to be loaded on the plating apparatus and thereby to avoid an increase in installation area of the plating apparatus, while maintaining a desired throughput of the plating apparatus. Since the manipulation for selecting the substrate holder according to the substrate to be processed is not required, the operation of the device is simplified compared with the conventional configuration and the cost of the plating apparatus can be reduced. 
     In this embodiment, the substrate holder  18  has two types of electrical contact end parts, the first electrical contact end part  93   a  and the second electrical contact end part  94   a . However, the present invention is not limited to this example, and the substrate holder  18  may has another electrical contact end part which, for example, comes into contact with the substrate at a different position in the radial direction from the first electrical contact end part  93   a  and the second electrical contact end part  94   a . In that case, it is possible to supply power to a larger number of types of substrates through the substrate holder  18 . 
     Next, an electrical contact according to another embodiment will be described. The electrical contact according to the another embodiment to be described below differs in the shape of the end part from the electrical contact  92  described with  FIG. 4  through  FIG. 11 , and the electrical contact end part of the electrical contact described below can be adopted instead of the first electrical contact end part  93   a  and/or the second electrical contact end part  94   a.    
       FIG. 12A  is a side view of the electrical contact according to the another embodiment,  FIG. 12B  is a front view of this electrical contact, and  FIG. 12C  is a top view of this electrical contact. As shown in the drawings, an electrical contact  95  has an electrical contact end part  95   a , a substantially plate-like electrical contact body  95   c  formed integrally with the electrical contact end part  95   a , and a leg portion  95   b  which is formed in a lower part of the electrical contact body  95   c  and comes into contact with the conductor  88  (see  FIG. 3 ). 
     The electrical contact end part  95   a  of the electrical contact  95  shown in  FIG. 12  has a bent-up portion  95   e  (corresponding to one example of the protruding portion) formed by being bent up into a spoon shape at the tip. When power is supplied to a substrate using this electrical contact  95 , the lower surface of the bent-up portion  95   e  comes into contact with the front plane surface portion, front bevel portion, or front shoulder portion of the substrate. 
     Since this electrical contact  95  has the bent-up portion  95   e , the bottom surface of the bent-up portion  95   e  reliably comes into contact with surfaces of different angles such as the front plane surface portion, front bevel portion, and front shoulder portion, and can supply power stably to the substrate. 
       FIG. 13A  is a side view of the electrical contact according to another embodiment, and  FIG. 13B  is a perspective view of the electrical contact end part. As shown in  FIG. 13A , an electrical contact  96  has an electrical contact end part  96   a , a substantially plate-like electrical contact body  96   c  formed integrally with the electrical contact end part  96   a , and a leg portion  96   b  which is formed in a lower part of the electrical contact body  96   c  and comes into contact with the conductor  88  (see  FIG. 3 ). 
     As shown in  FIG. 13B , the electrical contact end part  96   a  has a sharp claw portions  96   e  (corresponding to one example of the protruding portion) at the tip. When power is supplied to a substrate using this electrical contact  96 , the claw portions  96   e  come into contact with the front plane surface portion, front bevel portion, or front shoulder portion. Since the electrical contact end part  96   a  has the claw portions  96   e , the electrical contact  96  can supply power even to a substrate with a resist formed on it as the claw portions  96   e  penetrate the resist. 
       FIG. 14  is a side view of an electrical contact according to another embodiment. As shown in  FIG. 14 , an electrical contact  97  has an electrical contact end part  97   a , a substantially plate-like electrical contact body  97   c  formed integrally with the electrical contact end part  97   a , and a leg portion  97   b  which is formed in a lower part of the electrical contact body  97   c  and comes into contact with the conductor  88  (see  FIG. 3 ). 
     The electrical contact end part  97   a  of the electrical contact  97  shown in  FIG. 14  has a curved portion  97   e  (corresponding to one example of the protruding portion) which is bent up to have a curved lower surface. When power is supplied to a substrate using this electrical contact  97 , the lower surface of the curved portion  97   e  comes into contact with the front plane surface portion, front bevel portion, or front shoulder portion of the substrate. According to this electrical contact  97 , since the curved portion  97   e  reliably comes into contact with surfaces of different angles such as the front plane surface portion, front bevel portion, and front shoulder portion, power can be supplied stably to the substrate. 
       FIG. 15A  is a side view of an electrical contact according to another embodiment, and  FIG. 15B  is a front view of this electrical contact. As shown in the drawings, an electrical contact  98  has an electrical contact end part  98   a , a substantially plate-like electrical contact body  98   c  formed integrally with the electrical contact end part  98   a , and a leg portion  98   b  which is formed in a lower part of the electrical contact body  98   c  and comes into contact with the conductor  88  (see  FIG. 3 ). 
     The electrical contact end part  98   a  of the electrical contact  98  shown in  FIG. 15  has a convex portion  98   e  (corresponding to one example of the protruding portion) formed by embossing. When power is supplied to a substrate using this electrical contact  98 , the lower surface of the convex portion  98   e  comes into contact with the front plane surface portion, front bevel portion, or front shoulder portion of the substrate. 
     According to this electrical contact  98 , since the convex portion  98   e  reliably comes into contact with surfaces of different angles such as the front plane surface portion, front bevel portion, and front shoulder portion, power can be supplied stably to the substrate. 
     Next, a method for plating the substrate W held by the substrate holder  18  having been described above will be described. First, the bonded substrate W or the substrate W for forming a bump or a rewiring line is held by the substrate holder  18 . The substrate holder  18  holding the bonded substrate W or the substrate W for forming a bump or a rewiring line is housed in the copper plating unit  38  shown in  FIG. 1  and immersed in a plating solution. At this point, the bonded substrate W or the substrate W for forming a bump or a rewiring line is disposed in the plating solution to face an anode, with the surface to be processed of the substrate W and the plane of the anode substantially in parallel to each other. Voltage is applied to the bonded substrate W or the substrate W for forming a bump or a rewiring line and the anode while being immersed in the plating solution. The metal ion contained in the plating solution is thereby reduced on the surface to be processed of the bonded substrate W or the substrate W for forming a bump or a rewiring line, and a film is formed on the surface to be processed. 
     Here, when the substrate holder  18  holds the bonded substrate W, the first electrical contact end part  93   a  (bent-up portion  93   e ) of the electrical contact  92  comes into contact with the active wafer W 2  at the position (first position P 1 ) on the front plane surface portion  101  as shown in  FIG. 10 , and power is supplied to the seed layer  104  of the active wafer W 2 . On the other hand, when the substrate holder  18  holds the substrate W for forming a bump or a rewiring line, the second electrical contact end part  94   a  (bent-up portion  94   e ) of the electrical contact  92  comes into contact with the substrate W for forming a bump or a rewiring line at the position (second position P 2 ) on the front bevel portion  102  or the front shoulder portion  103  as shown in  FIG. 11 , and power is supplied to the seed layer  104 . Thus, the substrate holder  18  allows power to be supplied to substrates having different properties for plating. 
     REFERENCE SIGNS LIST 
     
         
           10  Cassette 
           12  Cassette table 
           14  Aligner 
           16  Spin dryer 
           18  Substrate holder 
           20  Substrate mounting/dismounting part 
           22  Substrate carrier device 
           24  Stocker 
           26  Pre-wet tank 
           28  Pre-soak tank 
           30   a  First water washing tank 
           30   b  Second water washing tank 
           32  Blow tank 
           34  Plating tank 
           36  Overflow tank 
           38  Copper plating unit 
           40  Substrate holder carrier device 
           42  First transporter 
           44  Second transporter 
           50  Rail 
           52  Loading plate 
           54  First holding member 
           56  Hinge 
           58  Second holding member 
           60  Seal member 
           60   a  Lip portion 
           60   b  Lip portion 
           61  Base part 
           62  Seal holder 
           64  Presser ring 
           64   a  Ridge 
           74  Clamper 
           80  Holding surface 
           82  Hand 
           88  Conductor 
           90  Support 
           92  Electrical contact 
           93   a  First electrical contact end part 
           93   b  First leg portion 
           93   c  First electrical contact body 
           93   d  Hole 
           93   e  Bent-up portion 
           94   a  Second electrical contact end part 
           94   b  Second leg portion 
           94   c  Second electrical contact body 
           94   d  Hole 
           94   e  Bent-up portion 
           95  Electrical contact 
           95   a  Electrical contact end part 
           95   b  Leg portion 
           95   c  Electrical contact body 
           95   e  Bent-up portion 
           96  Electrical contact 
           96   a  Electrical contact end part 
           96   b  Leg portion 
           96   c  Electrical contact body 
           96   e  Claw portion 
           97  Electrical contact 
           97   a  Electrical contact end part 
           97   b  Leg portion 
           97   c  Electrical contact body 
           97   e  Curved portion 
           98  Electrical contact 
           98   a  Electrical contact end part 
           98   b  Leg portion 
           98   c  Electrical contact body 
           98   e  Convex portion 
           101  Front plane surface portion 
           102  Front bevel portion 
           103  Front shoulder portion 
           104  Seed layer 
           105  Resist 
           106  Apex portion 
           107  Back shoulder portion 
           108  Back bevel portion 
           109  Back surface portion 
         P 1  First position 
         P 2  Second position 
         W Substrate 
         W 1  Support substrate 
         W 2  Active wafer