Abstract:
A system for processing wafers that will reduce the amount of time required for polishing wafers, increase worker safety while performing the process and increase the percentage of acceptable wafers after processing.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to wafer polishing pads and, more specifically, to a wafer polishing pad holder having a cavity for placing one or more polishing pad disc(s) components in the cavity. The components comprise spacer disc(s) and polishing pad disc(s) with the cavity also retaining aqueous solutions ranging from water to abrasive slurries. 
         [0003]    The walls of the holder cavity are designed with any numbers of recesses so that the spacer disc(s) and polishing pad disc(s) can be manufactured with or without peripheral tabs of substantially similar shape as the recesses thereby providing spacer disc(s) and polishing pad disc(s) that will rotate during the polishing process or not rotate during the process. 
         [0004]    2. Description of the Prior Art 
         [0005]    There are other polishing pads designed for polishing wafers. While these devices may be suitable for the purposes for which they where designed, they would not be as suitable for the purposes of the present invention as heretofore described. 
         [0006]    It is thus desirable to provide a polishing pad holder having a base with a peripheral wall where disc components of the polishing process can be placed therein. 
         [0007]    It is further desirable to provide recesses with the interior of the peripheral wall so that the polishing pad components can be manufactured as rotative or non-rotative disc components of the polishing process. 
       SUMMARY OF THE PRESENT INVENTION 
       [0008]    Polishing wafers to millimeter thicknesses is fraught with pitfalls beyond the operators&#39; control. Simply because it is a mechanical process involving fluid dynamic and the rotational speed of the article to be polished that easily results in a small percentage of acceptable wafers. Currently, assembling a polishing pad for mounting workpieces thereto mandates diligence, care and man hours. 
         [0009]    The present invention provides a system that will reduce man hours required, increase worker safety by not having to attach a polishing pad to the polishing table or plate for each wafer polishing cycle. 
         [0010]    The system of the present invention provides a polishing pad holder having a cavity where components of the polishing process are mounted within the cavity to effect a predetermined result on the wafer workpieces. 
         [0011]    Furthermore, the system provides for rotating and non rotating disc components within the cavity. Again providing the ability to vary the polishing process applied to the wafer depending on the type of wafer material and the desired result. 
         [0012]    A primary object of the present invention is to provide a polishing pad holder having a base with a peripheral wall rising therefrom for receiving at least one polishing pad component therein. 
         [0013]    Another object of the present invention is to provide a polishing pad holder where the peripheral wall has a plurality of recesses therein. 
         [0014]    Yet another object of the present invention is to provide a polishing pad holder that will retain aqueous solutions within said cavity during a wafer polishing process. 
         [0015]    Still yet another object of the present invention is to provide spacers and polishing pads with and without peripheral tabs of similar shape as the peripheral wall recesses so that said spacers and polishing pad can be rotating or non-rotating within said cavity during the polishing process. 
         [0016]    Additional objects of the present invention will appear as the description proceeds. 
         [0017]    The present invention overcomes the shortcomings of the prior art by providing a system for processing wafers that will reduce the amount of time required for polishing wafers, increase worker safety while performing the process and increase the percentage of acceptable wafers after processing. 
         [0018]    The foregoing and other objects and advantages will appear from the description to follow. In the description reference is made to the accompanying drawings, which forms a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. In the accompanying drawings, like reference characters designate the same or similar parts throughout the several views. 
         [0019]    The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         [0020]    In order that the invention may be more fully understood, it will now be described, by way of example, with reference to the accompanying drawing in which: 
           [0021]      FIG. 1  is an illustrative view of the present invention in use. 
           [0022]      FIG. 2  is a perspective view of the base of the polishing pad holder of the present invention. 
           [0023]      FIG. 3  is a perspective bottom view of the base of the polishing pad holder. 
           [0024]      FIG. 5  is an illustrative view of the assembled polishing pad holder. 
           [0025]      FIG. 6  is an illustrative view of the polishing pad holder having slurry held therein. 
           [0026]      FIG. 7  is an illustrative view of the polishing pad holder having water held therein. 
           [0027]      FIG. 8  is an illustrative view of the polishing pad holder. 
           [0028]      FIG. 9  is an illustrative view of the polishing pad holder. 
           [0029]      FIG. 10  is an illustrative view of the present invention. 
           [0030]      FIG. 11  is an illustrative view of the present invention. 
           [0031]      FIG. 12  is an illustrative view of the present invention. 
           [0032]      FIG. 13  is an illustrative view of the present invention. 
           [0033]      FIG. 14  is an illustrative view of the present invention. 
           [0034]      FIG. 15  is an illustrative view of one partially assembled embodiment of a 
           [0035]      FIG. 16  is an illustrative view of an assembled embodiment of the present invention. 
           [0036]      FIG. 17  is an illustrative view of the present invention. 
       
    
    
     DESCRIPTION OF THE REFERENCED NUMERALS 
       [0037]    Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views, the figures illustrate the Wafer Polishing Pad Holder Template of the present invention. With regard to the reference numerals used, the following numbering is used throughout the various drawing figures. 
         [0038]      10  Wafer Polishing Pad Holder Template of the present invention 
         [0039]      12  rotating head 
         [0040]      14  workpiece template 
         [0041]      16  polishing machine 
         [0042]      18  polishing pad 
         [0043]      20  pad holder base 
         [0044]      21  top peripheral side of  20   
         [0045]      22  bottom of  20   
         [0046]      24  milled island of  20   
         [0047]      25  ribs of  20   
         [0048]      26  milled recessed notch 
         [0049]      27  non-spin disc tab 
         [0050]      28  inside pocket 
         [0051]      30  adhesive layer of  20   
         [0052]      32  paper cover of  30   
         [0053]      34  polishing pad holder ring 
         [0054]      35  bottom side of  34   
         [0055]      36  double side tape of  34   
         [0056]      38  paper backing of  36   
         [0057]      40  cavity 
         [0058]      42  non-metallic material 
         [0059]      44  clear, shiny Mylar disc 
         [0060]      46  slurry 
         [0061]      48  water 
         [0062]      50  non-spin polishing disc 
         [0063]      52  red disc surface 
         [0064]      54  black disc surface 
         [0065]      56  double sided polishing pad accessory 
         [0066]      58  Napcon material film 
         [0067]      60  non-spin spacer 
         [0068]      62  top of  34   
         [0069]      64  plastic surface disc 
         [0070]      66  hard polishing pad 
         [0071]      68  soft polishing pad 
         [0072]      70  spin spacer or disc 
         [0073]      72  polishing pad material one 
         [0074]      74  polishing pad material two 
         [0075]      76  milled disc 
         [0076]      78  process one assembly 
         [0077]      80  process two assembly 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0078]    The following discussion describes in detail one embodiment of the invention (and several variations of that embodiment). This discussion should not be construed, however, as limiting the invention to those particular embodiments, practitioners skilled in the art will recognize numerous other embodiments as well. For definition of the complete scope of the invention, the reader is directed to appended claims. 
         [0079]      FIG. 1  is an illustrative view of the present invention in use. The present invention is a revolutionary polishing pad holder template  10  that achieves quick change of pad, quick pad dressing process, less labor, lower injury occurrence, reduces down time and provides better polishing results. The special design of “quick change” polishing pad allows the ability to stock polishing pad and final polishing pad on the same machine. Shown is the rotating head  12 , workplace template  14 , polishing machine  16  and polishing pad  18 . 
         [0080]      FIG. 2  is a perspective view of the base of the polishing pad holder of the present invention. Shown is the pad holder base  20  manufactured of non metal material or any fiberglass material with a bottom peripheral side  22 , a grid-like plurality of ribs  23  defining milled island(s)  24  forming the inside pocket  28  of the pad holder for back pressure relief. The milled islands  24  can be cut in any desired shape and size with the number of milled notches  26  a design consideration and can be more or less than the number depicted serving to prevent ring spin-off. 
         [0081]      FIG. 3  is a perspective bottom view of the polishing pad holder base  20 . Shown is an adhesive layer  30  on the back side  22  of the pad holder base  20  having a peelable removable paper liner  32  so that when removed the adhesive layer  30  on the base will adhere to any polishing machine table or platen. 
         [0082]      FIG. 4  is an illustrative view of the bottom side  35  of the polishing pad holder ring  34 . Shown is the polishing pad holder ring  34  having double sided tape  36  with a peelable removable paper backing  38  so that when removed it can be fixedly attached to the aforementioned polishing pad holder base. The ring is also preferably manufactured from a non-metallic material  42 . As illustrated, a predetermined plurality of milled notches  26  are disposed within the interior ring wall so that when mounted to the holder base forms a cavity  40  for mounting rotating and non-rotating spacer discs, milled disc(s), mylar disc(s) and polishing disc(s) therein and to retain aqueous solutions within the cavity during a wafer polishing process. 
         [0083]      FIG. 5  is an illustrative view of the assembled polishing pad holder. Illustrated is the polishing pad holder  10  comprising a polishing pad holder base  20  with a top side  21  secured to the bottom of said polishing pad holder ring  34  together forming a centralized cavity  40  having a plurality of interior periphery wall notches  26 . The cavity  40  will help in retaining the slurry (chemical and water) inside the cavity  40  longer during a polishing process. Also shown is a single side adhesive Mylar disc  44  fixed to the top side of the holder base with the non adhesive (shiny) side up. The assembled base, ring and Mylar form a completed polishing pad holder ready for use. 
         [0084]      FIG. 6  is an illustrative view of the polishing pad holder  10  having slurry  46  held within the cavity  40  formed by the polishing pad holder base  20 , the polishing pad holder ring  34  and the Mylar disc  44 . 
         [0085]      FIG. 7  is an illustrative view of the polishing pad holder  10  having water  48  held within the cavity  40  formed by the polishing pad holder base  20 , the polishing pad holder ring  34  and the Mylar disc  44 . 
         [0086]      FIG. 8  is an illustrative view of the polishing pad holder  10 . Shown is the polishing pad holder  10  having a spacer disc or non-spin polishing pad disc  50  with a contour substantially conforming to the polishing pad holder cavity  40  formed by the polishing pad holder base  20  and the polishing pad holder ring  34  thereby preventing independent rotation of the spacer disc or polishing pad disc held therein. The plurality of recessed notches  26  within the cavity  40  into which the disc tabs  27  reside is a design consideration and therefore may be more or less than depicted. The non spin spacer or polishing pad material protects the cavity  40  from being worn out and can be removed and replaced when worn out or not needed. The thickness of the spacer or polishing pad material can vary as required. It is also envisioned by the present invention that color can be used to identify a specific thickness, shown as red  52  in the illustration, which will expedite in changing to a desired thickness through color coding. 
         [0087]      FIG. 9  is an illustrative view of the polishing pad holder  10 . Shown is the polishing pad holder  10  having a spacer disc or non-spin polishing disc  50  having a contour substantially conforming to the polishing pad holder cavity  40  formed by the polishing pad holder base  20  and the polishing pad holder ring  34  thereby preventing independent rotation of the spacer disc or non-spin polishing disc  50  held therein. The plurality of recessed notches  26  within the cavity  40  is a design consideration and therefore may be more or less than depicted. The non spin spacer disc or polishing disc  50  protects the cavity  40  from being worn out and can be removed and replaced when worn out or not needed. The thickness of the spacer disc or polishing disc  50  can vary as required. It is also envisioned by the present invention that color can be used to identify a specific thickness, shown as black  54  in the illustration, which will expedite in changing to a desired thickness through color coding. 
         [0088]      FIG. 10  is an illustrative view of the polishing pad holder  10  of the present invention. Shown is a double sided polishing pad accessory  56  with Mylar  58  on top of the non spin spacer or polishing disc  50 . The polishing pad holder  10  is ready to be used. Different accessories can be utilized with the polishing pad holder  10  for different polishing processes. The polishing pad holder  10  can be of any size, thickness and cavity (pocket) depth from two inches and up. 
         [0089]      FIG. 11  is an illustrative view of the present invention. Shown is the Napcon material film  58  on top of the non spin spacer  60  or polishing pad material. The polishing pad holder  10  is ready to be used. Different accessories can be utilized with the polishing pad holder for different polishing processes. The polishing pad holder can be of any size, thickness and cavity  40  (pocket) depth from two inches and up as determined by the top  62  of the pad holder ring  34 . 
         [0090]      FIG. 12  is an illustrative view of the present invention. Shown are plastic material surface disc  64  with milled islands on both sides, Mylar material, hard polishing pad  66  and soft polishing pad  68 . Different materials can mount in the same disc. It can become a single or a double side polishing pad depending on what material it is mounted on double side polishing pad can be used to polish on the same machine by selecting the right pad by flipping over from disc surface  1  and  2  or exchange a disc surface pad in minutes. 
         [0091]      FIG. 13  is an illustrative view of the present invention. Shown is the Napcon material film  58  on top of the spin spacer or disc  70  within the cavity  40  formed by the polishing pad ring  34 . The polishing pad holder  10  is ready to be used. Different accessories can be utilized with the polishing pad holder template for different polishing processes. The polishing pad holder template can be of any size, thickness and cavity (pocket) depth from two inches and up. 
         [0092]      FIG. 14  is an illustrative view of the present invention. Shown, completed double side polishing pad  56  layered inside the cavity (pocket)  40  of the polishing pad holder  10 . If the disc surface pad is mounted with spacers, the formation is a double side spacer disc. 
         [0093]      FIG. 15  is an illustrative view of one partially assembled embodiment of a double sided polishing pad  56  of the present invention. Shown is Mylar material used as a non spin spacer  60 . The spacer is placed within the holder cavity to extend the life expectancy of the holder. It can be removed or changed to different thickness to accommodate the height adjustment of the polishing pad. Also shown is a milled disc  76  having polishing pad material one  72  on one side with polishing pad material two  74  placed on the other side of the milled disc  76 . 
         [0094]      FIG. 16  is an illustrative view of an assembled embodiment of the present invention. Shown are the wafer polishing spin components  70  comprising wafer polishing pad holder assembly  10  ready to run process one  78 . 
         [0095]      FIG. 17  is an illustrative view of the present invention. Shown, complete polishing holder assembly  10  ready to use for process two  80 . 
         [0000]    It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above. 
         [0096]    While certain novel features of this invention have been shown and described and are pointed out in the annexed claims, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention. 
         [0097]    Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.