Patent Abstract:
A semiconductor wafer saw and method of using the same for dicing semiconductor wafers are disclosed comprising a wafer saw including variable lateral indexing capabilities and multiple blades. The wafer saw, because of its variable indexing capabilities, can dice wafers having a plurality of differently sized semiconductor devices thereon into their respective discrete components. In addition, the wafer saw with its multiple blades, some of which may be independently laterally or vertically movable relative to other blades, can more efficiently dice silicon wafers into individual semiconductor devices.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application is a divisional of application Ser. No. 09/875,063 filed Jun. 6, 2001, pending. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     This invention relates generally to a method and apparatus for dicing or sawing semiconductor substrates having encapsulated semiconductor devices thereon and more specifically to a saw and chuck and method of using the same employing using multiple indexing techniques and multiple blades for more efficient sawing from an array of semiconductor devices on a substrate.  
         [0004]     2. State of the Art  
         [0005]     An individual integrated circuit semiconductor device, semiconductor die, or chip is usually formed from a larger structure known as a semiconductor wafer, which is usually comprised primarily of silicon, although other materials such as gallium arsenide and indium phosphide are also sometimes used. Each semiconductor wafer has a plurality of integrated circuits arranged in rows and columns with the periphery of each integrated circuit being rectangular. Typically the wafer is sawn or “diced” into rectangularly shaped discrete integrated circuits along two mutually perpendicular sets of parallel lines or streets lying between each of the rows and columns thereof. Hence, the separated or singulated integrated circuits are commonly referred to as dice.  
         [0006]     One exemplary wafer saw includes a rotating dicing blade mounted to an aluminum hub and attached to a rotating spindle, the spindle being connected to a motor. Cutting action of the blade may be effected by diamond particles bonded thereto, or a traditional “toothed” type blade may be employed. Many rotating wafer saw blade structures are known in the art. The present invention is applicable to any saw blade construction so further structures will not be described herein.  
         [0007]     Because semiconductor wafers in the art usually contain a plurality of substantially identical integrated circuits arranged in rows and columns, two sets of mutually parallel streets extending perpendicular to each other over substantially the entire surface of the wafer are formed between each discrete integrated circuit and are sized to allow passage of a wafer saw blade between adjacent integrated circuits without affecting any of their internal circuitry. Prior to the sawing of a semiconductor wafer to singulate the wafer and to create individual semiconductor die from the wafer, a piece of tape, typically referred to as wafer tape, is applied to the back side of the wafer so that once the wafer has been singulated, the individual semiconductor die remain attached to the wafer tape for further handling and processing.  
         [0008]     Once the wafer tape has been applied to the back side of the wafer, a typical wafer sawing operation includes attaching the semiconductor wafer to a wafer saw carrier, mechanically, adhesively or otherwise as known in the art and mounting the wafer saw carrier on the table of the wafer saw. A blade of the wafer saw is passed through the surface of the semiconductor wafer, either by moving the blade relative to the wafer, the table of the saw and the wafer relative to a stationary blade, or a combination of both. To dice the wafer, the blade cuts precisely along each street, returning back over (but not in contact with) the wafer while the wafer is laterally indexed to the next cutting location. Once all cuts associated with mutually parallel streets having one orientation are complete, either the blade is rotated 90° relative to the wafer or the wafer is rotated 90°, and cuts are made through streets in a direction perpendicular to the initial direction of cut. Since each integrated circuit on a conventional wafer has the same size and rectangular configuration, each pass of the wafer saw blade is incrementally indexed one unit (a unit being equal to the distance from one street to the next) in a particular orientation of the wafer. As such, the wafer saw and the software controlling it are designed to provide uniform and precise indexing in fixed increments across the surface of a wafer.  
         [0009]     Once the individual or singulated semiconductor die have been sawed, the semiconductor die are further processed by being removed from the wafer tape, attached to substrates and packaged, such as the semiconductor die being adhesively attached to a substrate in a board-over-chip configuration (BOC), connections made between the semiconductor die and the circuits of the substrate by wire bonding, and the semiconductor die and portions of the substrate being encapsulated. While the semiconductor die and substrate may be individually handled, it is more efficient to process a plurality of semiconductor die, each semiconductor die being individually mounted, on a substrate having a configuration providing for each individually mounted semiconductor die thereon and circuits for connection with each individually semiconductor die as well as for the encapsulation of each individual semiconductor die mounted on the substrate.  
         [0010]     However, existing process equipment and apparatus do not have the capability of singulating the packaged semiconductor die on a substrate when a plurality of semiconductor die are contained in an array on a substrate.  
       BRIEF SUMMARY OF THE INVENTION  
       [0011]     Accordingly, an apparatus and method for sawing semiconductor substrates, including substrates having a plurality of semiconductor devices of different sizes and/or shapes therein, is provided. In particular, the present invention provides a saw and method of using the same capable of “multiple indexing” of a saw blade or blades to provide the desired cutting capabilities. As used herein, the term “multiple indexing” contemplates and encompasses both the lateral indexing of a saw blade at multiples of a fixed interval and at varying intervals which may not comprise exact multiples of one another. Thus, for conventional substrate and/or wafer configurations containing a number of equally sized integrated circuits, the wafer saw and method herein can substantially simultaneously saw the substrates and/or wafers with multiple blades and therefore cut more quickly than single blade wafer saws known in the art. Moreover, for wafers having a plurality of differently sized or shaped integrated circuits, the apparatus and method herein provides a multiple indexing capability to cut nonuniform dice from the same wafer.  
         [0012]     The present invention includes a substrate chuck mounted on a table used in conjunction with the saw for holding a substrate having an array of encapsulated semiconductor devices mounted thereon for singulation. The chuck comprises a chuck table, at least one cutting pedestal, at least one clamp, at least one clamp pedestal, and an alignment apparatus for aligning a substrate for singulation in the chuck. The alignment apparatus may comprise at least one alignment pin having a portion thereof attached to the chuck table and having a portion engaging the substrate to be singulated or a recess in the chuck table for receiving the substrate to be singulated therein.  
         [0013]     In one embodiment, a single-blade, multi-indexing saw is provided for cutting a substrate containing variously configured semiconductor devices thereon which may be encapsulated. By providing multiple-indexing capabilities, the saw can sever the wafer into differently sized mounted encapsulated semiconductor devices corresponding to the configuration of the semiconductor devices contained thereon.  
         [0014]     In another embodiment, a saw is provided having at least two wafer saw blades spaced a lateral distance from one another and having their centers of rotation in substantial parallel mutual alignment. The blades are preferably spaced apart a distance equal to the distance between adjacent areas for cutting the substrate. With such a saw configuration, multiple parallel cuts through the substrate can be made substantially simultaneous, thus essentially increasing the speed of cutting a substrate by the number of blades utilized in tandem. Because of the small size of the individual semiconductor devices mounted and/or encapsulated on the substrate and the correspondingly small distances between adjacent cutting areas on the substrate, it may be desirable to space the blades of the saw more than one cutting area apart. For example, if the blades of a two-blade saw are spaced two cutting areas apart, a first cut would cut the first and third laterally separated cutting areas. A second pass of the blades through the substrate would cut through the second and fourth streets. The blades would then be indexed to cut through the fifth and seventh streets, then sixth and eighth, and so on.  
         [0015]     In yet another embodiment, at least one blade of a multi-blade saw is independently raisable relative to the other blade or blades when only a single cut is desired on a particular pass of the carriage. Such a saw configuration has special utility where the blades are spaced close enough to cut in parallel on either side of larger encapsulated semiconductor devices, but use single blade capability for dicing any smaller integrated circuits. For example, a first pass of the blades of a two-blade saw could cut a first set of adjacent cutting areas of the substrate defining a column of larger semiconductor devices on the substrate. One blade could then be independently raised or elevated to effect a subsequent pass of the remaining blade cutting along a cutting area of the substrate that may be too laterally close to an adjacent street to allow both blades to cut simultaneously, or that merely defines a single column of narrower semiconductor devices. This feature would also permit parallel scribing of the surface of the substrate to mutually isolate conductors from, for example, tie bars or other common links required during fabrication, with subsequent passage by a single blade indexed to track between the scribe lines to completely sever or singulate the adjacent portions of the substrate.  
         [0016]     In still another embodiment, at least one blade of a multi-blade saw is independently laterally translatable relative to the other blade or blades. Thus, in a two-blade saw, for example, the blades could be laterally adjusted between consecutive saw passes of the sawing operation to accommodate different widths between cutting areas of the substrate. It should be noted that this embodiment could be combined with other embodiments herein to provide a wafer saw that has blades that are both laterally translatable and independently raisable, or one translatable and one raisable, as desired. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0017]      FIG. 1  is a schematic side view of a first preferred embodiment of a wafer saw in accordance with the present invention;  
         [0018]      FIG. 2  is a schematic front view of the wafer saw illustrated in  FIG. 1 ;  
         [0019]      FIG. 3  is a schematic front view of a second embodiment of a wafer saw in accordance with the present invention;  
         [0020]      FIG. 4  is a schematic front view of a third embodiment of a wafer saw in accordance with the present;  
         [0021]      FIG. 5  is a top view of an array of semiconductor devices on a substrate;  
         [0022]      FIG. 6  is a bottom view of the array of semiconductor devices on a substrate illustrated in drawing  FIG. 5 ;  
         [0023]      FIG. 7  is a top view of a substrate chuck according to the present invention for the sawing of the array of semiconductor devices on a substrate illustrated in drawing  FIG. 5  and drawing  FIG. 6 ;  
         [0024]      FIG. 8  is a side view taken along line  8 - 8  of drawing  FIG. 7  of the substrate chuck according to the present invention;  
         [0025]      FIG. 9  is a schematic view of a silicon semiconductor wafer having variously sized semiconductor devices therein to be diced with the saw;  
         [0026]      FIG. 10  is a schematic view of another silicon semiconductor wafer having variously sized semiconductor devices therein to be diced with the saw;  
         [0027]      FIG. 11  is a top view of a portion of a semiconductor substrate bearing conductive traces connected by tie bars;  
         [0028]      FIG. 12  is a top view of a portion of a semiconductor substrate bearing three different types of components formed thereon;  
         [0029]      FIG. 13  is a top view of an alternative substrate chuck according to the present invention for the sawing of the array of semiconductor devices on a substrate illustrated in drawing  FIG. 5  and drawing  FIG. 6 ; and  
         [0030]      FIG. 14  is a side view taken along line  8 - 8  of drawing  FIG. 13  of the substrate chuck according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0031]     As illustrated in drawing  FIGS. 1 and 2 , an exemplary wafer saw  10  to be used with the present invention is comprised of a base  12  to which extension arms  14  and  15  suspended by support  16  are attached. A substrate saw blade  18  is attached to a spindle or hub  20  which is rotatably attached to the extension arm  15 . The blade  18  may be secured to the hub  20  and extension arm  15  by a threaded nut  21  or other means of attachment known in the art. The substrate saw  10  also includes a translatable substrate table  22  movably attached in both X and Y directions (as indicated by arrows in drawing  FIGS. 1 and 2 ) to the base  12 . The table  22  used to hold the chuck  500 ,  500 ′ (see drawing  FIGS. 7, 8 ,  13 , and  14 ) of the present invention thereon by any suitable attachment apparatus. Alternatively, blade  18  may be translatable relative to the table  22  to achieve the same relative X-Y movement of the blade  18  to the table  22 . A substrate  24  to be scribed or sawed at  24 ′ may be securely mounted to the table  22 . As used herein, the term “saw” includes scribing of a substrate, the resulting scribe line not completely extending through the substrate. Further, the term “substrate” includes any suitable type substrate to which a semiconductor device may be attached, such as FR-4 board, silicon substrate, traditional full semiconductor wafers of silicon, gallium arsenide, or indium phosphide and other semiconductor materials, partial wafers, and other equivalent structures known in the art wherein a semiconductor material table or substrate is present. For example, so-called silicon-on-insulator or “SOI” structures, wherein silicon is carried on a glass, ceramic or sapphire (“SOS”) base, or other such structures as known in the art, are encompassed by the term “substrate” as used herein. Likewise, “semiconductor substrate” may be used to identify wafers and other structures to be singulated into smaller elements.  
         [0032]     The saw  10  is capable of lateral multi-indexing of the table  22  having a chuck  500  or blade  18  or, in other words, translatable from side-to-side in drawing  FIG. 2  and into and out of the plane of the page in drawing  FIG. 1 , various nonuniform distances. As noted before, such nonuniform distances may be mere multiples of a unit distance, or may comprise unrelated varying distances, as desired. Accordingly, a substrate  24  having variously sized integrated circuits or other devices or components therein may be sectioned or diced into its non-uniformly sized components by the multi-indexing saw  10 . In addition, as previously alluded, the saw  10  may be used to create scribe lines or cuts that do not extend through the substrate  24 . The substrate  24  can then subsequently be diced by other methods known in the art or sawed completely through after the blade  18  has been lowered to traverse the substrate to its full depth or thickness.  
         [0033]     Before proceeding further, it will be understood and appreciated that design and fabrication of a substrate saw for use with the present invention having the previously referenced, multi-indexing capabilities, independent lateral blade translation and independent blade raising or elevation is within the ability of one of ordinary skill in the art, and that likewise, the control of such a device to effect the multiple-indexing (whether in units of fixed increments or otherwise), lateral blade translation and blade elevation may be effected by suitable programming of the software-controlled operating system, as known in the art. Accordingly, no further description of hardware components or of a control system to effectuate operation of the apparatus of the invention is necessary.  
         [0034]     Referring now to drawing  FIG. 3 , another illustrated embodiment of a substrate saw  30  is shown having two laterally spaced blades  32  and  34  with their centers of rotation “C” in substantial parallel alignment transverse to the planes of the blades. For a rectangular substrate or a conventional substantially circular silicon semiconductor wafer each having a plurality of similarly configured semiconductor devices  42  (not shown) or integrated circuits  42  (not shown) arranged in evenly spaced rows and columns, the blades can be spaced a distance “D” substantially equal to the distance between adjacent areas  44  or streets  44  (not shown) defining the space between each integrated circuit  42 . In addition, if the areas  44  of a substrate  40  or streets  44  of wafer  40  are too closely spaced for side-by-side blades  32  and  34  to cut along adjacent streets, the blades  32  and  34  can be spaced a distance “D” substantially equal to the distance between two or more areas  44  or streets  44 . For example, a first pass of the blades  32  and  34  could cut along streets  44   a  and  44   c  and a second pass along streets  44   b  and  44   d.  The blades could then be indexed to cut the next series of areas or streets and the process repeated as desired number of times. If, however, the semiconductor devices  42  of a substrate  40  or integrated circuits  42  of a wafer  52  have various sizes, such as integrated circuits  50  and  51  as illustrated in drawing  FIG. 9 , at least one blade  34  is laterally translatable relative to the other blade  32  to cut along the areas or streets  44 , such as street  56 , separating the variously sized integrated circuits  50 . The blade  34  may be variously translatable by a stepper motor  36  having a lead screw  38  or by other devices known in the art, such as high precision gearing in combination with an electric motor or hydraulics, or other suitable mechanical drive and control assemblies. For a substrate  40  or wafer  52 , the integrated circuits, such as integrated circuits  50  and  51 , may be diced by setting the blades  32  and  34  to simultaneously cut along areas  58  or  59  (see drawing  FIG. 6 ) streets  56  and  57 , indexing the blades, setting them to a wider lateral spread and cutting along areas  56  or  57  or areas  58  and  59 , indexing the blades while monitoring the same lateral spread or separation and cutting along streets  60  and  61 , and then narrowing the blade spacing and indexing the blades and cutting along other areas (not shown) and streets  62  and  63 . The substrate  40  or wafer  52  could then be rotated 90° and the blade separation and indexing process repeated for areas  58  or  59  or vice versa (see drawing  FIG. 6 ) and streets  64  and  65 , streets  66  and  67 , and streets  68  and  69 .  
         [0035]     As illustrated in drawing  FIG. 4 , a wafer saw  70  according to the present invention is shown having two blades  72  and  74 , one of which is independently raisable (as indicated by an arrow) relative to the other. As used herein, the term “raisable” includes vertical translation either up or down. Such a configuration may be beneficial for situations where the distance between adjacent cutting areas of a substrate and/or streets of a wafer is less than the minimum lateral achievable distance between blades  72  and  74 , or only a single column of narrow semiconductor devices or semiconductor dice is to be cut, such as at the edge of a substrate or wafer. Thus, when cutting a wafer  80 , as better illustrated in drawing  FIG. 10  depicting a wafer, the two blades  72  and  74  can make a first pass along streets  82  and  83 . One blade  72  can then be raised, the wafer  80  indexed relative to the unraised blade  74  and a second pass performed along street  84  only. Blade  72  can then be lowered and the wafer  80  indexed for cutting along streets  85  and  86 . The process can be repeated for streets  87  (single-blade pass),  88 , and  89  (double-blade pass). The elevation mechanism  76  for blade  72  may comprise a stepper motor, a precision-geared hydraulic or electric mechanism, a pivotable arm which is electrically, hydraulically or pneumatically powered, or other means well-known in the art.  
         [0036]     Finally, it may be desirable to combine the lateral translation feature of the embodiment of the substrate saw  30  illustrated in drawing  FIG. 3  with the independent blade raising feature of the wafer saw  70  of drawing  FIG. 6 . Such a wafer saw could use a single blade to cut along areas or streets that are too closely spaced for dual-blade cutting or in other suitable situations, and use both blades to cut along variously spaced areas or streets where the lateral distance between adjacent cutting areas or streets is sufficient for both blades to be engaged.  
         [0037]     It will be appreciated by those skilled in the art that the embodiments herein described while illustrating certain embodiments are not intended to so limit the invention or the scope of the appended claims. More specifically, this invention, while being described with reference to substrates for semiconductor devices thereon, either encapsulated or not, semiconductor wafers containing integrated circuits or other semiconductor devices, has equal utility to any type of substrate to be scribed or singulated. For example, fabrication of test inserts or chip carriers formed from a silicon (or other semiconductor substrate) or wafer and used to make temporary or permanent chip-to-wafer, chip-to-chip, and chip-to-carrier interconnections and that are cut into individual or groups of inserts, as described in U.S. Pat. Nos. 5,326,428 and 4,937,653, may benefit from the multi-indexing method and apparatus described herein.  
         [0038]     For example, illustrated in drawing  FIG. 11 , a semiconductor substrate  100  may have traces  102  formed thereon by electrodeposition techniques required connection of a plurality of traces  102  through a tie bar  104 . A two-blade saw in accordance with the present invention may be employed to simultaneously scribe substrate  100  along parallel lines  106  and  108  flanking a street  110  in order to sever tie bars  104  of adjacent substrate segments  112  from their associated traces  102 . Following such severance, the two columns of adjacent substrate segments  112  (corresponding to what would be termed “dice” if integrated circuits were formed thereon) are completely severed along street  110  after the two-blade saw is indexed for alignment of one blade therewith, and the other blade raised out of contact with substrate  100 . Subsequently, when either the saw or the substrate carrier is rotated 90°, singulation of the segments  112  is completed along mutually parallel streets  114 . Thus, substrate segments  112  for test or packaging purposes may be fabricated more efficiently in the same manner as dice and in the sizes and shapes.  
         [0039]     As shown in drawing  FIG. 12 , a portion of a substrate  200  is depicted with three adjacent columns of varying-width segments, the three widths of segments illustrating batteries  202 , chips  204  and antennas  206  of a semiconductor device, such as an RFID device. With all of the RFID components formed on a single substrate  200 , an RFID module may be assembled by a single pick-and-place apparatus at a single work station. Thus, complete modules may be assembled without transfer of partially assembled modules from one station to the next to add components. Of course, this approach may be employed to any module assembly wherein all of the components are capable of being fabricated on a single semiconductor substrate. Fabrication of different components by semiconductor device fabrication techniques known in the art is within the ability of those of ordinary skill in the art, and therefore no detailed explanation of the fabrication process leading to the presence of different components on a common wafer or other substrate is necessary. Masking of semiconductor device elements not involved in a particular process step is widely practiced, and so similar isolation of entire components is also easily effected to protect the elements of a component until the next process step with which it is involved.  
         [0040]     Further, the saw used with the present invention has particular applicability to the fabrication of custom or nonstandard integrated circuits or other components, wherein a capability for rapid and easy die size and shape adjustment on a substrate-by-substrate or wafer-by-wafer basis is highly beneficial and cost-effective. In the present saw it may be desirable to have at least one blade of the independently laterally translatable blade configuration be independently raisable relative to the other blade or blades, or a single blade may be both translatable and raisable relative to one or more other blades and to the target substrate or wafer. In addition, while for purposes of simplicity, some of the preferred embodiments of the substrate saw are illustrated as having two blades, however, the saw may have more or less than two blades.  
         [0041]     Referring to drawing  FIG. 5 , a first side  300  of a substrate  40  is illustrated having a plurality of semiconductor devices  42  located thereon. Each semiconductor device  42  having been previously encapsulated in a suitable molding process. The substrate  40  may be of any suitable material, such as described herein.  
         [0042]     Referring to drawing  FIG. 6 , another side  302  of the substrate  40  is illustrated having the plurality of semiconductor devices  42  connected to a plurality of solder balls or suitable type connectors  306  through suitable circuits (not shown) on substrate  40  and from the encapsulated semiconductor devices  42 . The substrate  40  may contain circuits thereon, such as illustrated in drawing  FIG. 11 .  
         [0043]     Referring to drawing  FIG. 7 , illustrated in a top view is a dicing chuck  500  suitable for use with the table  22  of the substrate saw  10  and the substrate  40  illustrated in drawing  FIGS. 5 and 6 . The chuck  500  comprises a chuck table  502  having a shaft  528  ( FIG. 8 ) attached thereto for mounting on the table  22  using suitable apparatus, a plurality of cutting pedestals  504  having the desired spacing to mate with the semiconductor devices  42  of substrate  40  and connectors  306  of another side  302  of substrate  40 , a pair of clamps  506  mounted on clamp pedestals  508  (see drawing  FIG. 8 ), and one or more alignment pins  510 , if desired, for aligning the substrate  40  on the chuck  500 . Each cutting pedestal  504  includes a portion  512  having an aperture  514  therein for mating with the portion of the semiconductor device  42  on another side  302  thereof and portions  516  having a plurality of recessed areas  518  therein for mating with the connectors  306  in areas  308  (see drawing  FIG. 6 ) of another side  302  of substrate  40 . The aperture  514  in the cutting pedestal  504  may be connected to a source of vacuum (not shown) to help retain the semiconductor devices  42  on the cutting pedestal  504 . The shape, size and spacing of the recessed areas  518  on each cutting pedestal  504  will vary with the type, size, and spacing of the connectors  306  of another side  302  of substrate  40 . The clamps  506  mounted on clamp pedestals  508  may be secured thereto by any suitable type of retaining apparatus, such as a threaded member  520 . The chuck  500  may be fabricated from any suitable material, such as metal commonly used for the dicing of substrates having semiconductor devices thereon.  
         [0044]     Referring to drawing  FIG. 8 , the chuck  500  illustrated in a side view. As shown, the apertures  514  in each cutting pedestal  504  has an aperture  522  connected to aperture  524  which, in turn, is connected to aperture  526  in the chuck shaft  528  to supply vacuum from a source of vacuum to each cutting pedestal  504 . The shape, size, configuration, and layout of the apertures  522 ;  524 , and  526  may be any suitable desired configuration to supply vacuum to each cutting pedestal  504 . The alignment pins  510  mate with alignment apertures  43  in the substrate  40  (see drawing  FIGS. 5 and 6 ). The alignment pins  510  may be any desired configuration, size, and shape to mate with any alignment aperture in substrate  40 . The threaded member  520  may be any suitable type to retain the substrate clamps  506  on the clamp pedestals  508 . The substrate clamps  506  may be of any suitable shape, size, and configuration to mate with portions of the substrate  40  to retain portions thereof on the cutting pedestals  504  and, if desired, on clamp pedestal  508 .  
         [0045]     Each of the cutting pedestals  504  is spaced from an adjacent cutting pedestal  504  by a space  503  and space  505  which also extends both between the cutting pedestals  504  and one the exterior of the cutting pedestals  504  to allow a saw blade  18  of a saw as described herein to cut a substrate  40  into the desired number of singulated semiconductor devices  42 , each singulated semiconductor device  42  having a plurality of connectors  306  attached to one side thereof. In this manner, an array of any desired number of semiconductor devices  42  on a substrate  40  may be retained in the chuck  500  to be singulated by a saw  10  having one or more blades  18 . Additionally, since the depth and width of a saw  10  may vary, any spacing of the semiconductor devices  42  on the substrate  40  may be used.  
         [0046]     Referring to drawing  FIGS. 13 and 14 , an alternative chuck  500 ′ according to the present invention is illustrated. In the alternative chuck  500 ′ of the present invention, the alignment pins  510  have been eliminated. The chuck table  502  includes a recess  510 ′ therein having the size, configuration, and shape to mate and align a substrate  40  within the recess  510 ′ prior to being retained therein by the clamps  506  on clamp pedestals  508 . In this manner, a substrate  40  may be located by the perimeter of the recess  510 ′ on the cutting pedestals  504  being retained thereon by a vacuum supplied through aperture  514  and clamps  506 . Except for the elimination of the alignment pins  510  and the addition of an alignment recess  510 ′ in the table  502  of the chuck  500 ′, the chuck  500 ′ is the same as the chuck  500  illustrated in drawing  FIG. 7  and drawing  FIG. 8 .  
         [0047]     The chuck  500  and  500 ′ of the present invention may include alterations and features, changes, additions, and deletions which are intended to be within the scope of the invention. For instance, the chuck may be of any size, shape, and configuration. The chuck may have any desired number of cutting pedestals of any size, shape, and configuration thereon, may have any desired number, shape, size, and configuration of clamps and clamp pedestals, may have any desired alignment apparatus for a substrate thereon, etc.  
         [0048]     Thus, while certain representative embodiments and details have been shown for purposes of illustrating the invention, it will be apparent to those skilled in the art that various changes in the invention disclosed herein may be made without departing from the scope of the invention, which is defined in the appended claims.

Technology Classification (CPC): 8