Method and apparatus for plating substrates

Abstract

Plating apparatus comprises a gear mechanism for imparting planetary motion to a set of holders for holding substrates in a plating bath. The holders are typically a non-conductive material such as plastic. The holders are coupled to a bearing comprising first and second plastic races and metallic balls therebetween. This embodiment reduces the amount of plastic moving against plastic, and therefore reduces the amount of wear, friction, and generation of contaminant parts. The holders comprise a central mandrel and outer mandrels connected to end pieces. The substrates are held at their outer edges between the outer mandrels and the central mandrels.

1 . Apparatus comprising: 
 a holder for holding workpieces in a plating bath;    a bearing having a first race and a second race, said first race being coupled to said holder, said second race being rotatable with respect to said first race, said first and second races being non-metallic, a metal mechanical interface between said first and second races; and    a rotating member coupled to said second race of said bearing for imparting motion to said holder.    
     
     
         2 . Apparatus of  claim 1  wherein the metal mechanical interface reduces the amount of contaminant particle generation that would occur if said holder slid against said member.  
     
     
         3 . Apparatus of  claim 2  wherein said metal mechanical interface comprises a set of balls or rollers.  
     
     
         4 . Apparatus of  claim 3  wherein said workpieces are magnetic disk substrates, said apparatus comprising a set of gears for imparting planetary motion to said substrates.  
     
     
         5 . Method for plating comprising: 
 placing one or more workpieces within a holder;    placing said holder in a plating bath; and    imparting motion to a mechanical member, said mechanical member being coupled to a first race of a bearing, said holder being coupled to a second race of said bearing, said first and second races being plastic, a metallic interface being provided between said first and second races, said mechanical member imparting motion to said holder via said bearing.    
     
     
         6 . Method of  claim 5  wherein said mechanical member comprises a rotating wheel, said first race being coupled to said wheel, and said metallic interface comprises balls or rollers.  
     
     
         7 . Method of  claim 6  wherein planetary motion is imparted to said one or more workpieces, and said workpieces are magnetic disk substrates.  
     
     
         8 . Apparatus comprising: 
 a plating bath;    a holder comprising a central mandrel and a plurality of other mandrels, said holder for holding a plurality of sets of workpieces such that each set of said workpieces is held by at least one of said other mandrels and against an associated side of said central mandrel, said holder holding said workpieces in said plating bath; and    a mechanical member imparting motion to said holder.    
     
     
         9 . Apparatus of  claim 8  wherein said workpieces are magnetic disk substrates and said mechanical member comprises a wheel for rotating said holder.  
     
     
         10 . Apparatus of  claim 9  further comprising a set of gears for imparting planetary motion to said holder.  
     
     
         11 . Apparatus of  claim 10  wherein at least one of said other mandrels is removable to facilitate loading and unloading of said substrates into said holder.  
     
     
         12 . Method for plating comprising: 
 placing a plurality of sets of workpieces in a holder, said holder comprising a central mandrel and a plurality of other mandrels, each set of said workpieces being held against an associated side of said central mandrel and against an associated plurality of said other mandrels;    placing said holder in a plating bath; and    applying motion to said holder.    
     
     
         13 . Method of  claim 12  wherein said applying motion to said holder comprises applying planetary motion to said holder.  
     
     
         14 . Method of  claim 13  wherein said workpieces are magnetic disk substrates, said substrates have an opening, and said placing of said substrates in said holder comprises: 
 providing a tool having a tool mandrel extending through the openings of said set of substrates;    manipulating said tool mandrel so that said set of substrates rests against said central mandrel and at least one of said other mandrels; and    removing said tool mandrel from said openings of said set of substrates.    
     
     
         15 . Method of  claim 14  further comprising removing said substrates from said holder, said removing comprising: 
 removing said holder from said bath;    placing said tool mandrel into said openings of said substrates; and    lifting said substrates out of said holder.    
     
     
         16 . Plating apparatus comprising: 
 a container for holding a plating solution;    one or more elongated members for holding a plurality of workpieces in said plating solution; and    first and second metallic plates adjacent first and second sides of said plurality of workpieces.    
     
     
         17 . Apparatus of  claim 16  wherein the presence of said metallic plates increases the similarity of the plating conditions of the workpieces adjacent to said metallic plates to the plating conditions of the workpieces that are surrounded by other workpieces.  
     
     
         18 . Method comprising: 
 placing a plurality of workpieces in a holder, said holder comprising first and second metallic plates adjacent first and second sides of said plurality of workpieces;    placing said holder and plurality of workpieces in a plating solution.    
     
     
         19 . Method of  claim 18  wherein the presence of said metallic plates increases the similarity of the plating conditions of the workpieces adjacent to said metallic plates to the plating conditions of the workpieces that are surrounded by other workpieces.  
     
     
         20 . Method comprising: 
 providing a substrate holder having one or more mandrels for holding a set of workpieces at an outer edge of said workpieces, said workpieces having an inner opening, said one or more mandrels being held at least at one end by an end piece;    holding said set of workpieces by inserting an elongated tool through said inner openings of said set of workpieces; and    moving said set of workpieces with said elongated tool so that said workpieces rest against said one or more mandrels, said end piece having a slot therein, said act of moving comprising moving said tool through said slot.    
     
     
         21 . Method of  claim 20  further comprising coupling one or more removable mandrels to said end piece, said removable mandrels holding said workpieces in place.  
     
     
         22 . Method of  claim 20  further comprising placing said holder into a plating bath and plating material onto said workpieces.  
     
     
         23 . Method of  claim 22  further comprising removing said holder from said plating bath and removing said workpieces from said holder.  
     
     
         24 . Method of  claim 23  wherein said workpieces are magnetic disk substrates and said holder comprises two end pieces, each end piece being coupled to an associated end of said mandrels.  
     
     
         25 . Method comprising: 
 providing a set of workpieces in a holder in a plating bath, said holder comprising a set of mandrels coupled to an end piece, said workpieces being held at their outer edges by said mandrels, said workpieces having an inner opening, said end piece comprising a slot for accommodating a tool;    removing said holder and workpieces from said plating bath;    passing an elongated tool into said inner opening of said workpieces; and    withdrawing said workpieces from said holder with said tool, said method comprising passing said tool through said slot.    
     
     
         26 . Method of  claim 25  wherein said workpieces are magnetic disk substrates, and said holder comprises two end pieces, each of said mandrels being coupled to said two end pieces.  
     
     
         27 . Method of  claim 25  wherein at least one of said mandrels is removable, said method further comprising removing said at least one removable mandrel from said holder prior to withdrawing said elongated tool into said inner opening of said workpieces.  
     
     
         28 . Apparatus comprising: 
 a set of mandrels for holding a set of workpieces at an outer edge of said workpieces, wherein said workpieces each have a central opening;    a first end piece coupled to a first end of said mandrels;    a second end piece coupled to a second end of said mandrels, said second end piece having a slot therein for accommodating a tool, wherein said workpieces are loaded into said apparatus by inserting said tool through said inner openings and sliding said tool through said slot so that said workpieces rest against said mandrels.    
     
     
         29 . Apparatus of  claim 28  wherein at least one of said mandrels is removable from said apparatus.  
     
     
         30 . Apparatus of  claim 28  further comprising a gear system for imparting planetary motion to said workpieces.  
     
     
         31 . Apparatus comprising: 
 a holder comprising one or more elongated members for holding workpieces;    a stationary member having an opening;    a pin for extending through said opening in said stationary member and engaging with said holder to prevent said holder from moving during loading and unloading of said holder.    
     
     
         32 . Apparatus of  claim 31  wherein said stationary member is a wall of said apparatus, said apparatus further comprising a second wall, said first and second walls holding a gear mechanism for imparting motion to said holder.  
     
     
         33 . Apparatus of  claim 31  further comprising a gear coupled to said holder, wherein said pin engages with teeth of said gear.  
     
     
         34 . Apparatus of  claim 31  further comprising a gear coupled to said holder, wherein said pin engages with an opening in said gear.  
     
     
         35 . Method comprising: 
 placing a pin through a stationary member so that said pin engages with a holder for holding workpieces;    loading workpieces into said holder, said pin preventing said holder from moving during loading.    
     
     
         36 . Method of  claim 35  further comprising; 
 removing said pin from said holder; and    placing said holder and said workpieces in a plating solution to plate said workpieces.    
     
     
         37 . Method of  claim 36  further comprising: 
 removing said holder from said plating solution;    causing said pin to engage with said holder; and    unloading said workpieces from said holder.    
     
     
         38 . Method of  claim 35  wherein said holder is coupled to a gear and said pin engages with teeth of said gear.  
     
     
         39 . Method of  claim 35  wherein said holder is coupled to a gear and said pin engages with an opening in said gear.  
     
     
         40 . Method comprising: 
 providing a holder containing workpieces;    placing a pin through a stationary member to engage with said holder to thereby prevent said holder from moving; and    removing said workpieces from said holder.    
     
     
         41 . Method of  claim 40  wherein said holder is coupled to a gear and said pin engages with teeth of said gear.  
     
     
         42 . Method of  claim 40  wherein said holder is coupled to a gear and said pin engages with an opening in said gear.  
     
     
         43 . Apparatus for plating substrates, said substrates being planar and having a centrally defined opening, said apparatus comprising: 
 a plating bath; and    a holder comprising a plurality of mandrels for holding said substrates at their outer edges in said plating bath.    
     
     
         44 . Apparatus of  claim 43  wherein at least one of said mandrels is removable for facilitating the loading and unloading of said substrates from said holder.  
     
     
         45 . Apparatus of  claim 43  further comprising a gear mechanism for imparting planetary motion to said holder.  
     
     
         46 . Method comprising: 
 placing substrates in a holder, said substrates being generally planar and having an opening therein, said holder comprising a plurality of mandrels for holding said substrates at outer edges of said substrates;    placing said holder and said substrates in a plating bath; and    plating said substrates.    
     
     
         47 . Method of  claim 46  further comprising: 
 removing at least one of said mandrels from said holder prior to placing said substrates in said holder; and    placing said at least one mandrel back onto said holder after placing said substrates in said holder.    
     
     
         48 . Method of  claim 46  further comprising imparting planetary motion to said substrates during plating.  
     
     
         49 . Method comprising: 
 removing a holder from a plating bath, said holder comprising a plurality of mandrels for holding a set of generally planar substrates at outer edges of said substrates, said substrates having an opening therein;    removing at least one of said mandrels from said holder; and    removing said substrates from said holder.