Patent Publication Number: US-10773420-B2

Title: Device and method for cleaving a substrate

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation-in-part of application of U.S. patent application Ser. No. 15/339,923 filed Oct. 31, 2016, which is a continuation-in-part of application of U.S. patent application Ser. No. 13/664,125 filed on Oct. 30, 2012, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/558,122 filed on Nov. 10, 2011, the contents of which are hereby incorporated by reference. This application is also a continuation-in-part of application of U.S. patent application Ser. No. 15/191,293 filed Oct. 31, 2016 which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/183,674 filed Jun. 23, 2015, the contents of which are hereby also incorporated by reference. 
    
    
     TECHNICAL FIELD 
     This description relates generally to a methods and devices for cleaving substrates typically used in the semiconductor industry and more specifically to cleaving crystalline, mono-crystalline, and amphorous materials such as a silicon or gallium arsenide, or sapphire, glass or the like. 
     BACKGROUND 
     Cleaving substrates produced by the semiconductor industry is a common operation to separate circuits processed on a common substrate into individual units for subsequent packaging typically in a highly automated and precise operation. During fabrication the circuits may often be sampled and tested as part of the quality control effort or the like. Since testing is not a high volume operation it is not as highly automated as production operations, and typically utilizes less automated methods to cleave the substrates or wafers into samples for testing. 
     As circuit features are decreased in size it has become more difficult to accurately cleave the substrates for testing by hand, or other laboratory suitable methods. Currently, an alternative to hand cleaving is to use expensive and highly accurate machinery that is available, that tends to be more than is needed in the testing lab. 
     Currently, there are two typical approaches to cleaving mono-crystalline substrate materials and the like. The first approach is a low-cost, low-sophistication option, which requires a highly skill-dependent procedure (based on experience and expertise and training). It involves manually aligning by human sight a substrate, and using hand tools, such as scriber pens or rudimentary cleaving apparatus. In particular the procedure involves manually scribing a line on the back side of a substrate using a scribing knife, placing the wafer over a cleaving bar from the glass industry, and manually pushing down on the work piece using two pins. 
     The second approach, which is more high cost but less error prone, utilizes a mechanized approach that is capital intensive in both equipment cost and operator training and, as a result, is used by approximately the top 25 semiconductor manufacturers (worldwide). Such an approach may utilize microscopic alignment to a target feature and an induced shock wave to cause cleaving. This later type of cleaving apparatus is not only complicated to make and use, but requires a much larger footprint and takes valuable space in the lab and has an ongoing high cost of operation. 
     These approaches have shortcomings that may include on the low tech side: a reliance on a pre-scribed cleave line in the silicon, significant human skill and or training to operate, high variability due to the human factor. On the high precision end of the available equipment spectrum the equipment available may be very large and require high capital initial expenditure, with high operating costs, complexity, and is overly precise for many operations. 
     Accordingly, it would be desirable to provide a machine to cleave substrates that is highly accurate, low cost and suitable for use in a testing lab or similar environment. 
     SUMMARY 
     The following presents a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not identify key/critical elements of the invention or delineate the scope of the invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later. 
     The device includes a stationary stage upon which a sample is initially and approximately positioned for cleaving with the aid of a fixable guide coupled to a stage. A block structure including an indenter with a scribe is movable along an edge of the fixed stage. The block also includes a vertically movable cleaving bar. The indenter is slidably (vertically) disposed in the block and under spring bias to keep it in an upward position. The block is coupled to a top portion of a Newport stage, and the bottom portion of the Newport stage is attached to the housing body or platform. The top portion of the Newport stage and the bottom portion of the Newport stage are slidably coupled in a linear direction via a conventional ball bearing mechanism. Movement of the top portion relative to the bottom portion is controlled via a knob controlled conventional micrometer mechanism. The block includes a bottom breaker pin disposed in line with the indenter scribe. The cleaving bar includes two breaking pins positioned on either side to the bottom breaking pin disposed in the block. 
     The device may further include a vacuum pump and switch coupled to vacuum holes in the stage to hold a sample in place. The device may further include a microscope positioned to view the indenter and sample under magnification. A camera may also be included to view the indenter and sample area, and is typically coupled to a computer equipped with software to project a virtual guide line on the image displayed to aid in positioning the indenter. In a further alternative example a laser device may be positioned and coupled to the device so that a laser line is projected on the sample that is indicative of the indenter position over the sample. 
     Many of the attendant features will be more readily appreciated as the same becomes better understood by reference to the following detailed description considered in connection with the accompanying drawings. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The present description will be better understood from the following detailed description read in light of the accompanying drawings, wherein: 
         FIG. 1  is a front view of a first example of a device for cleaving a substrate. 
         FIG. 2  is a side view of a first example of a device for cleaving a substrate. 
         FIG. 3  is a front isometric view of a first example of a device for cleaving a substrate. 
         FIG. 4  is a top view of a first example of a device for cleaving a substrate. 
         FIG. 5  is a partial cutaway of the stage showing a first example of a device for cleaving a substrate showing the exemplary Newport stage and an indenter with a compound dial. 
         FIG. 6  is a full cutaway of the stage showing a first example of a device for cleaving a substrate showing the exemplary Newport stage and an indenter with a compound dial. 
         FIG. 7  is a front view of a second example of a device for cleaving a substrate. 
         FIG. 8  is a right side view of a second example of a device for cleaving a substrate. 
         FIG. 9  is an isometric frontal view of a second example of a device for cleaving a substrate. 
         FIG. 10  is a partial front view of a second example of a device for cleaving a substrate. 
         FIG. 11  is a detail view of the second example of a device for cleaving a substrate of  FIG. 10  along the line  8 - 8 . 
         FIG. 12  is a frontal view of the of a second example of a device for cleaving a substrate. 
         FIG. 13  is a detail view of the of a second example of a device for cleaving a substrate of  FIG. 12  along the line  9 - 9 . 
         FIG. 14  is a partial front view of the second example of a device for cleaving a substrate. 
         FIG. 15  is a detail view along the line  13 - 13  of  FIG. 14 . 
         FIG. 16  is a partial offset frontal view of the second example of a device for cleaving a substrate. 
         FIG. 17  is a detail view along the line  12 - 12  of the example of  FIG. 16 . 
         FIG. 18  is a partial side view of the example of  FIG. 16 . 
         FIG. 19  is a detail view along the line “C” of  FIG. 18 . 
         FIG. 20  is a front view of a third example illustrating a camera system example of a device for cleaving a substrate. 
         FIG. 21  is a flow chart of a method for cleaving a substrate. 
         FIG. 22  illustrates one step of a method for cleaving a substrate. 
         FIG. 23  illustrates an alternative step of the method of  FIG. 22 . 
         FIG. 24  illustrates an alternative step of the method of  FIG. 22 . 
         FIG. 25  illustrates a sample being cleaved by the method of  FIGS. 22-24  at first point in time. 
         FIG. 26  illustrates the sample of  FIG. 25  at a second point in time. 
         FIG. 27  is a cross sectional view of a portion of a sample S having an Indentation I according to at least one example of the present invention. 
     
    
    
     Like reference numerals are used to designate like parts in the accompanying drawings. 
     DETAILED DESCRIPTION 
     The detailed description provided below in connection with the appended drawings is intended as a description of the present examples and is not intended to represent the only forms in which the present example may be constructed or utilized. The description sets forth the functions of the example and the sequence of steps for constructing and operating the example. However, the same or equivalent functions and sequences may be accomplished by different examples. 
     The examples below describe a semiconductor wafer (or equivalently “substrate”) cleaving system. Although the present examples are described and illustrated herein as being implemented in a general wafer cleaving system, the system described is provided as an example and not a limitation. As those skilled in the art will appreciate, the present examples are suitable for application in a variety of different types of flat planar wafer cleaving systems utilized in cleaving crystalline and amphorous substrates. 
     The cleaving device provides a low cost, high quality, high accuracy cleaving of mono-crystalline material and other brittle substrates. Further, the device and method of the present invention offers successful cleaving through a target even with operators having minimal experience and expertise are using it, as it does not rely on human capabilities, such as hand and eye coordination, skill, or extensive training. 
     Further, the present invention is well-adapted for use for site specific, cross-sectional examination, with accuracy of a few (typically +/−10 microns) microns to the area of interest. The present invention works well with various samples including front-end, back-end, TSVs, and single die, for example. Another well-suited use includes a bulk removal step prior to FIB “focused ion beam”. The present invention has accuracy on the order of +/−10 microns. The present invention can be used to reduce large substrate pieces to small samples suitable for further preparation in ion beam and direct viewing in electron beam instruments. Yet another use for the present invention includes quality analysis of wafers where a quality analysis of wafer sample cross-section is desired, for example. Another use for the present invention includes sample preparation for failure analysis, process monitoring, and product development. 
     The description of directions regarding various movements may be referenced to the Cartesian coordinates  1008  shown in  FIG. 4 . In general, the x axis is motion from right to left on the stage, the y-axis is top to bottom positioning on the stage, and motion along the z axis is motion above or below the stage (vertical motion or position). 
       FIGS. 1-6  show a first example of a device for cleaving substrates  10 . 
     The device  10  includes a stationary stage  20  with a guide  92  for initially positioning a desired cleave line  1002  of a sample  1005  relative to an indenter mechanism  40  that includes a diamond tip scribe  48  used to indent the sample  1005  on the cleave line  1002  target. In sample preparation it is often desired to accurately place a cleave line  1002  since inaccurate positioning can ruin the devices on the sample or otherwise spoil the sample. The device  10  facilitates accurate cleaving of the sample by providing initial rough sample positioning on the fixed stage  20  followed by fine adjustment of the diamond tip scribe  48  position by moving the scribe. 
     The sample to be cleaved typically has at least one straight edge, and typically has at least one substantially right angle in its shape so that visual alignment is facilitated. For odd shaped samples the procedure outlined below may be modified as needed, including being aided by use of jigs and fixturing as known to those skilled in the art, to provide an edge for use against the guide  92  or otherwise aid in aligning a sample. An example would be a fixture (not shown) with a square outline and a round aperture for use in scribing a round silicon wafer positioned in the fixture. 
     To use the device  10  the cleaving bar  60  is typically initially in the lowered position. The sample cleave line position is first aligned with the diamond tip scribe  48  roughly by eye. Once the desired cleave line  1002  on a sample  1005  is approximately lined up with the scribe tip  48 , and the guide  92  is set  96  against the side of the sample. Next the diamond tip scribe  48  is moved in position with its position finely adjusted over the desired cleave line in a second iteration of alignment. The sample  1005  remains in a fixed position on the stage  20  with the vertical edge (y direction) of the sample resting against the guide  96 . As the fine adjustment is made, the diamond tipped scribe  48  may be moved from side to side (in the x direction) by turning a knob  24  adjustment actuating a conventional Newport Stage  16  upon which a block  14 , including a cleaving bar  60  and the indenter mechanism  40  with diamond tipped scribe  48  are attached. As the knob  24  is turned the diamond tipped scribe  48  moves (in the x direction) and can be precisely positioned over a desired indentation position for initiating a cleave (i.e., cleave line  1002 ) on the stationary substrate  1005 . It is worth pointing out that the diamond tipped scribe  48  protrudes slightly outward from the face of the cleaving bar  60 , so that when the diamond tipped scribe is lowered the substrate resting against the cleaving bar  60  may be indented. 
     Alignment of the diamond tipped scribe  48  over the cleave line  1002  position may be achieved by eye, by aid of magnification (typically with a microscope, or alternatively with a camera microscope combination shown in  FIG. 20 ). Also, to aid alignment a conventionally constructed laser device (not shown) may be used to project a line along a desired cleave line to aid the positioning of the scribe. In an alternative example of a positioning aid, a camera may be used in conjunction with a computing device (as shown in  FIG. 20 ) such as a laptop to run software that produces a cleave line on a screen image of the sample extending from the sample to the diamond tip scribe. Once the tip  48  is in position the projected line overlays the cleave line and the diamond tip. The diamond scribe tip  48  may then be brought down to indent the sample. 
     Once the diamond tip scribe  48  is finally aligned (as viewed either by eye or by use of the above described aids) using the micrometer  2602 , over the desired cleave indent location (typically along the edge of the sample  1005  abutting the cleaving bar  60 , where the cleave line  1002  is to begin) the indenter mechanism is lowered (z direction) in a controlled manner to indent the surface of the sample  1005 , typically to a controlled depth. This indent will serve to initiate, in a subsequent step, a cleave along cleave line  1002  in the sample that has been accurately placed thanks to the aid of the device  10 . The diamond tip  48  is attached to an indenter mechanism  40  that may include a compound screw and dial mechanism ( 2006  of  FIGS. 5-6 ) to control the indent depth in a repeatable manner. A first dial ( 2607  of  FIGS. 5-6 ) is used to lower the diamond tipped scribe  48  to just touching the surface of the sample. Next a second concentric outer dial ( 2608  of  FIGS. 5-6 ) is turned a desired number of degrees to provide an indent of a controlled and repeatable depth. 
     During the preceding, a horizontal edge (x direction) of the sample  1005  has been resting against the front face of a lowered cleaving bar  60 . To cleave the sample, the cleaving bar  60  is raised, exposing three breaking pins (lower pin  50  and upper pins  2501  of  FIG. 25 ) that will be used to cause the sample to cleave along a cleave line  1002  initiated at the indent made in the substrate. The breaking pins are disposed in the block  14  and its components (namely cleaving bar  60 ). The lower breaking pin  50  is positioned in the block  14  facing up, so that its apex is in alignment with the diamond tipped scribe  48  (y direction) and is positioned behind or rearwards of the scribe tip (in the y direction). Disposed in the cleaving bar  60  are an upper pair of breaking pins ( 2501  of  FIG. 25 ) positioned typically equidistant from the diamond tipped scribe  48 . 
     To cleave the sample a three point cleaving is utilized to create a clean cleave. The cleaving bar is raised and the sample&#39;s alignment against the vertical guide bar  92  is maintained as the sample is pushed back over the exposed lower breaking pin  50 , now that the cleaving bar  60  has been raised. This movement utilizing the guide  92  keeps the indent on the sample ( 2505  of  FIG. 25 ) in line with the apex of the bottom breaking pin  50 . The cleaving bar  60  is lowered and the two breaking pins ( 2501  of  FIG. 25 ) disposed in the cleaving bar  60  contact the substrate  1005  (note the indenter tip  48  need not be retracted as the thickness of the upper breaker pins causes the pins to contact the substrate surface well before the diamond tip  48  would when lowering the cleaving bar  60 ). As the cleaving bar  60  is pushed down (either manually, or equivalently by the screw  80 ) to provide an applied force ( 2503  of  FIG. 25 ) the sample is cleaved precisely along the desired cleave line  1002  due to its accurate positioning, and the maintaining of that position during the cleaving process that is aided by the device  10 . 
     The forces applied in the cleaving process are as follows: as the breaker bar  60  is pushed downward by means of the left and right handles  62 ,  62 , which causes the pins  2501  to apply a downward force on the top surface of the sample. This force is resisted by the pin  50 , which contacts the bottom surface of the sample. This bottom pin  50  aligns along the same vertical axis as the indentation on the top of the sample,—thus, the indenter, the indentation and the pin  50  all lie in the same line albeit at different heights on that common vertical axis—and the indenter is operable up and down whereas the pin  50  is stationary. Because the top surface of the sample has an indentation, the downward force transmitted through breaker pins  2501 , and resisted by pin  50 , is concentrated at the indentation and the sample is cleanly cleaved at the indentation. Now that the operation of the device  10  has been described in relation to its various components the components themselves will now be described in more detail. 
     Base  12  of the device for cleaving substrates is a platform upon which the device may be assembled. The base  12  is a non-moving part, typically made from aluminum or an equivalent material. 
     The stage  20  is fixed to the base  12 , and does not move during operation of the device  10  for cleaving substrates (or “samples”). The stage  20  provides a flat surface  22  upon which a substrate may be supported while being indented and cleaved. The stage  20  has a substantially flat top  22 , and is typically made from aluminum or its equivalent. The top of the stage  22  includes a horizontal (x direction) guide slot  94  that is narrower at the table top than at the bottom of the slot (i.e., an inverted “V” shaped slot). A vertical guide  92  and guide lock  96  are coupled to the stage  20  via the guide slot  94 . 
     The vertical guide  92  is a typically rectangular elongate member that may be moved across the stage (in the x direction) and may be locked in place via guide lock  96 . To maintain vertical orientation of the guide, a generally “V” shaped member  402  (conventionally constructed) is part of the guide, disposed in the guide slot  94  and thus slidably coupled to the generally “V” shaped guide slot  94 . Coupled to and at right angles to the “V” shaped member  402  is the guide  92 . Accordingly the guide  92  is thus slidably coupled to move across the stage  20  in the x direction, and provides a vertical (y axis  1008 ) surface against which the vertical edge of a sample  1005  may rest. 
     A conventionally constructed guide lock  96  allows the scribe guide to be fixed in place (typically by a knob and screw arrangement, disposed in a threaded aperture in the guide  92 , so that the end of the screw contacts the base of the grove  94 ) so that the guide  92  does not move when the screw is extended. In equivalent examples alternative constructions of the guide lock known to those skilled in the art may be employed. 
     A plurality of suction holes  86  may be disposed in the top  22  of the stage  20  to aid in keeping the sample  1005  in place. The holes may be coupled to a vacuum system (not shown) whereby activation of a vacuum “on” switch (not shown) draws suction through the holes  86  to more securely hold the sample temporarily to the stage. Deactivating the switch releases the sample. Although not depicted in the appended drawings, the device  10 , accordingly, includes a vacuum pump, power source, controller, and related components as would be readily understood in the art to provide and control the vacuum source. 
     The stage  20  also provides a recess underneath the stage top  22  to provide clearance for a movable Newport stage  16  partially diposed underneath the stage  20 , including the Newport stage adjustment mechanism  2601 ,  2602  that operates freely in the recess. The recess advantageously allows the adjustment knob  24  controlling movement of the diamond tip scribe  48  to be placed at a lower right hand corner of the device  10  so that the operator may conveniently turn the knob at a distance from the moving block  14  and diamond tip scribe  48 . 
     As previously mentioned the indenter mechanism  40 , including the diamond tip  48  is also movable in the x direction  1008  by turning the knob  24  coupled to the micrometer adjustment mechanism  2602 . The stage  20  is typically square or rectangular and one edge is in parallel alignment and abutting (with a small gap) a straight edge of the block  14 , so that when the block  14  (via the Newport stage movement) is moved in the x direction  1008 , the indenter  40  and cleaving bar  60  also move in the x direction in close proximity to the fixed stage  20  (and sample). 
     The Newport stage  16  includes Newport stage top portion that moves linearly from side to side in the x direction, is slidably coupled to a Newport stage bottom portion fixedly coupled to the base  12 . The Newport stage  16  with a micrometer adjustment  2602  is conventionally constructed and causes a top portion of the Newport stage  16  to move back and forth in the x direction  1008  with micrometer precision. 
     The Newport stage  16  is conventionally constructed and includes a bottom portion slidably coupled to a top portion in a linear direction (here oriented in the x direction). In this device  10  the Newport stage  16  is oriented so that it slides in the x direction  1008 . To move the top portion of the Newport stage in relation to the bottom portion a conventional micrometer screw mechanism  2602  is utilized. A knob  24  is coupled to a micrometer screw mechanism  2602  having a first end fixedly coupled to the Newport stage bottom portion and a second end coupled to the top portion of the Newport stage. The first end and second ends being coupled via a spindle  2601  with the intervening micrometer screw mechanism  2602 , such that turning the knob  24  causes the Newport stage top piece  2603 , and anything attached to it such as the diamond tip  48  to move in the horizontal x direction  2605  from side to side. 
     Since adjusting position with a micrometer takes many turns to move the diamond tip scribe  48  a small amount, the device  10  advantageously allows for rough positioning of the sample  1005  on the fixed stage  20  and final fine positioning of the scribe  48  to create an accurately positioned indent for cleave line  1002  on the sample  1005 . The micrometer adjustment tends to minimize the amount of time spent spinning the micrometer knob  24 . 
     A block assembly  14  is fixedly coupled to the movable (x direction) top portion of the Newport stage  16 . Block  14  supports an indenter mechanism  40  that is vertically slidable (in the Z or vertical direction) in a track  42  of  FIG. 3  in the block  14 , also a cleaving bar  60  is vertically slidable (in the Z or vertical direction) and coupled to the block  14  via guide rods  98 . 
     The indenter mechanism  40  is slidably coupled in the vertical direction to the block  14 , and may include conventional spring bias (not shown) to keep the surface of the indenter handle  44  pushed upwards (Z direction) against an end of a threaded rod  82  opposite to the knob end  80  of the threaded rod  82 . Such a retraction spring, is adapted to hold the slide member at a top position in the track. The threaded rod  82  is disposed in a threaded hole in a protrusion from the block  14 , or as shown in the FIGs, a rectangular tab member fixedly attached to the block and protruding from it. 
     Indenter mechanism  40  includes a handle  44  and the indenter  40  that further includes a tip holder  46  supporting and housing a diamond tip scribe tip  48 . The tip holder  46  for holding the scribe tip  48  is conventionally constructed. The diamond scribe tip  48  is positioned so that it slightly protrudes past the face of the cleaving bar  60 . This is so that in operation when the indenter mechanism  40  is depressed (z direction) the diamond tip scribe  48  contacts the sample  1005  that has been pushed up against the face of the cleaving bar  60 . Vertical motion (z direction) of the indenter mechanism through the cleaving bar  60  is facilitated by a let out channel disposed in the cleaving bar  60  so that clearance for the indenter mechanism  40  operating in the z direction is provided. 
     The indenter mechanism  40  is generally “T” shaped with the top of the “T” functioning as a handle  44 , and as a support structure to which a diamond tip  48  is coupled to the leg of the “T”. The diamond tip is shown in a vertical orientation. However, in equivalent examples the tip may be provided with a conventionally constructed adjustment mechanism so that it may be tilted at an angle deviating from the vertical. Such a mechanism may provide detents of specific angles or constructed to provide continuous variation in the deviating angle. 
     Although a 90-degree dent is described here the “scribe” could be made at various angles between 45-135 (+/−45) degrees (see  FIG. 24 ). A derivative of the current example may be implemented with this angle adjustment to improve positioning accuracy and minimize the contact area between the sample and the diamond tip. 
     The leg of the “T” is operable through the handle  44  to move the lever vertically downward, the lever further carrying the diamond tip scribe  48  in a tip holder  46 , the indenter  40  thus has a diamond tip  48  at a lower, leading edge. In alternative examples the diamond tip scribe may be replaced by equivalent scribing materials. 
     A precision knob  80  positions above the indenter  40 . The precision knob includes a threaded rod to enable precision adjustment of the indenter  40  relative to the stage  20 , or more particularly a sample on the stage. With the breaker or cleaving bar down, the operator turns the indenter drive precision knob  80  clockwise to push the indenter to touch the top of the sample, then by turning the knob  80  as needed the operator can feel pressure of the indenter and scribe as an indentation is made on the sample. This enables a more accurate and repeatable cleaving operation as the knob can be controlled in a precise manner whereby a vertical distance traveled can be translated into “turns of the knob” in an instruction manual for the operation. In alternative examples, knob  80  may be replaced by one or more dials constructed to bring the scribe down to the sample surface, and then to next provide a measured indent depth. 
     Cleaving bar  60  is made from aluminum or equivalent, and is slidably coupled (y direction) to right and left guide rods  98  anchored in the block  14 . For fine adjustments the cleaving bar  60  includes a scale  90  graduated in any desired units. The cleaving bar  60  includes a right handle  62 , and a left handle  62 . On a bottom surface of the cleaving bar  60  are disposed a pair of breaking pins ( 2501  of  FIG. 25 ) disposed equidistant from the point of the diamond tip  48 . 
     The pair of guide rods  98  vertically protrude through the right and left sides of the cleaving bar  60 . The guide rods may include bushings to better align the breaker  60  along a vertical axis. The guide rods are used in place of the sliders, described in the second example, below. The guide rods of this example provide a more stable alignment of the cleaving bar  60  and have less degrees of freedom compared to the sliders of the second example. 
     The cleaving bar  60  is typically one long piece extending the entire width of the stage. The bar  60  thus extends from a left side, which includes a left handle  62  to the right side having a corresponding right handle  64 . This bar  60  moves up and down on a vertical axis and the left handle  62  and right handle  62  cooperate to enable an operator to move the bar  60  up and down to break the sample after cleaving. The cleaving bar includes a left side breaker pin and a right side breaker pin, both located on a bottom surface of the bar and disposed on either side of a vertical axis defined between the indenter and pin  50 . This way when the bar  60  is in the down position, the left pin  70  and right pin  72  pushes evenly against the sample. The pins ( 70  and  72  of  FIG. 15 , and also  2501  of  FIG. 25 ) move vertically with the breaker bar  60  as seen in  FIG. 25 , for example. 
     Returning to the block  14  that provides support for the abovementioned mechanisms, it is generally “L” shaped when viewed from the side as in  FIG. 2 , and is fixedly coupled to the moving top piece of the Newport Stage  16 . An edge at the bottom of the “L” closely abuts the table top  22 , and adjusting the Newport stage via knob  24  and the associated micrometer mechanism  2602  causes the block  14  to move typically slowly in the x direction  1008  back and forth along edge of the fixed tabletop  12 . Clockwise and counterclockwise rotation of the knob  24  causes movement to the right or left in the x direction  1008  of the block  14 . The Micrometer mechanism  2602  may be equipped with a right hand screw, or equivalently a left hand screw. In equivalent examples the knob  24  may protrude from the left hand of the device. 
     The bottom of the “L” of the block  14  may include two vertical (in the z direction  1008 ) guide rods  98  over which the cleaving bar  60  with matching apertures may be slidably disposed. The upper surface of the bottom of the “L” is dimensioned such that it is generally the same height as the top of the stage  22 , so that when the cleaving bar  60  is resting against the upper surface of the bottom of the “L” the bottom of the cleaving bar  60  is approximately in the same x-y plane as the stage top  22 . 
     A breaking pin ( 50  of  FIG. 1 , and  FIG. 25 ) is disposed under the cleaving bar  60 . The pin  50  is centered to align with the vertical axis of the diamond tip  48  that creates the indentation on the sample ( 2502  of  FIG. 25 ). The diamond tip  48  indents the top surface of the sample  1005 , but the breaking pin  50  is arranged to contact the bottom surface of the sample when it is pushed further in along the guide  92 . The breaking pin  50  is positioned in line with the diamond tip  48  in the y direction  1008 , and behind it so that after the sample is indented by the indenter  40 , it may be pushed further back under the cleaving bar  60  so that the cleaving line  1002  defined by the indent on the work piece  1005  is centered side to side in the x direction  1008  over the breaking pin. The cleaving bar includes on its underside two breaking pins ( 2501   FIG. 25 ) so that as force is applied on either side of the breaker pin  50  as the cleaving bar  60  breaker pins are pressed down against the work piece  1005  cleaving at the indent, and thus the cleave line is achieved. 
     Upright portion of the “L” shaped block  14  may be unitary with the bottom of the “L”, or equivalently be a separate pieces attached together. Block  14  provides support and a channel for slidably coupling the indenter mechanism  40  in the vertical or, z direction  1008 . To keep the indenter  40  retracted upward until needed spring bias is provided by conventional methods to push the indenter mechanism upwards. Upward travel of the indenter is limited by a screw  80  threadabaly engaged in an aperture protruding from the block  14 . The indenter mechanism  40  may be pushed downward or up by utilizing the screw  80 , or equivalently the handle  44  of the indenter  40  may be pressed down to create an indent in a sample. 
       FIG. 5  is a cutaway view showing further detail of the exemplary Newport stage, and further including a more precise knob adjustment mechanism  2606  to control the indenter. Here the recess under the stage may be seen, as the stage has been partially cut away. The knob  2606  is conventionally constructed so that the inner  2607  and outer  2608  knobs turn independently. In operation the center knob is turned to position the diamond tip scribe just above the sample. Next the outer knob is turned a desired amount to further advance the diamond tip scribe into the sample to a given depth. The outer knob may include a scale to aid in repeatability. 
       FIG. 6  is a fully cutaway view (with the fixed stage completely removed) showing the exemplary Newport stage that is incorporated into the first example of the invention, and showing the micrometer coupling of the top and bottom portions of the Newport stage. 
       FIGS. 5 and 6  are cut away views that show the exemplary Newport stage  16  and adjustment mechanism. The stage includes a top piece  2603 , and a bottom piece  2604 , conventionally coupled by a conventionally constructed ball bearing race to allow linear movement—here oriented in the x direction. The stage is coupled to the knob  24  via a micrometer screw mechanism  2606 . The block assembly  14  shown with an indenter mechanism  40  moves in the X direction  2605  while the stage  20  holding the sample does not move. Since the entire top of the Newport stage is not needed, and to make the device  10  more compact, part of the Newport stage extends under the stage  20 , which has a cavity underneath to accommodate a portion of the Newport stage and the adjustment mechanism  2602 ,  2601 . The height of the cavity under the stage  20 , is sufficiently high so that the top portion of the Newport stage (including the block and the components attached to it) can move  2605  freely back and forth. 
     Typically the adjustment in the X direction is controlled by a micrometer screw mechanism  2602  coupled to a Newport stage bottom piece  2604  which is slidably coupled to a movable Newport stage top piece  2603 . The micrometer mechanism  2602  is coupled to the bottom piece  2604 , and the spindle  2601  is controlled by the micrometer mechanism  2602 . The spindle  2601  is coupled to the Newport stage top piece  2603 , whose movement is controlled by the micrometer screw mechanism  2602  to which it is coupled. The stage  2603  may be a commercially available High-Performance Low-Profile Ball Bearing Linear Stage such as the exemplary model  423  produced by the Newport corporation of Irvine Calif., a subsidiary of MKS Instruments or its equivalent. 
     The exemplary Newport stage may include a typically 3 inch square platform utilizing precision ball bearing construction—typically hardened balls rolling between opposing pairs of hardened and polished stainless steel rods providing better than 200 micro-radian angular deviation, for example. For stability, repeatability, and smooth motion, actuators may bear upon a hardened carbide insert. Springs may provide preloading against the actuator tip to eliminate backlash. Although the stage is typically capable of traveling a full 1 inch (25.4 mm) with an SM-25 micrometer drive, the actuator mounting blocks can be relocated to accommodate 0.5 inch (12.7 mm) drives like the SM-13. This stage can also be reconfigured into a left-handed version with the micrometer on the opposite side. A non-influencing lock (also reversible for left-handed configuration) provides positive stable positioning and guards against inadvertent adjustments. 
       FIGS. 7-19  show a second example of a device for cleaving substrates. In a second example the adjusting knob ( 80  of  FIG. 1 ) of the first example is omitted. Accordingly, the device  10  also includes a stage  20  disposed on the housing body  12 , the stage having a substantially flat top  22  and a mechanism for adjusting horizontally in the x-direction with sub-micron precision, and a knob  24  rotatably coupled to the mechanism for adjusting the stage. 
     The device  10  includes a base ( 912  of  FIG. 9 ) comprising a rear upright member  14  arranged on a lower frame  16  at about a right angle, the rear upright member including a first track  32 , a second track  34 , and a third track  36  wherein each track is substantially coplanar and extending vertically along a front face  30  of the rear upright member. 
     The device  10  further includes a lever comprising  40  a slide member  642  (of  FIG. 9 ) slideably inserted in the first track  32 , the lever further including a handle  44  and a retraction spring, which is adapted to hold the slide at a top position in the first track and the handle member is operable to move the lever vertically downward, the lever further carrying a diamond tip scribe  48  in a tip holder  46 , the indenter having a diamond tip  48  at a lower, leading edge. Although a 90-degree dent is described here this “scribe” could be made at various angles between about 45-13 5 (+/−45) degrees. A derivative of the current example could be implemented with this angle adjustment to improve positioning accuracy and minimize the contact area between the sample and the diamond tip. 
     The breaker assembly  60  is disposed on the rear upright member  14 . The breaker assembly is one solid bar having a left side  62  slideably inserted in the second track  34  and a right side  62  slideably inserted in the third track  36  and a center portion inserted in a center track. These three tracks cooperate to enable the bar  60  to move only in the up and down direction. 
     As in the first example, the breaker  60  includes a left and right breaker pin  70  and  72  (also see  2501  in  FIG. 25 ) on its bottom surface, and these pins operate as described in the first example. The breaker pins  50 ,  70 ,  71  position behind the scribe tip  48  as seen from the side is shown in  FIG. 19 . The arrangement of the breaker pins behind the scribe tip is the same in both the first and second examples of the cleaving device  10 . 
     It will be appreciated by those skilled in the art that any of the sub-components of the first and second examples can be combined with each other and still lie within the scope and spirit of the contemplated invention. 
       FIG. 20  shows a third example  200  of a device for cleaving substrates including a camera system. The camera includes a vertical mounting pole arranged perpendicular to table. Also an optical microscope may be included with the device to improve target and positioning accuracy. An optional vacuum or CDA may be included to create a vacuum, which will improve the cleanliness and accuracy of the cleave. For example, compressed air is used to hold the sample on the table, but also can be used to remove dust from the table by manually using a nozzle to dust off the table. In addition, suction devices, such as a vacuum pen, may be included for aiding in the removal of the cut sample from the table. 
     To provide magnification, the entire device, may be placed under an Optical Microscope with long working distance optics ( FIG. 20 ). Another option is to use a compact digital camera or other magnifying optics with the device. 
     A camera system  210  is coupled to the device  10 , of either the first or second examples. The camera system  200  includes a camera  210  mounted to a camera support  220  that allows for vertical positioning of the camera  210  and movement 360 degrees around this vertical axis and about 360 degrees rotation parallel to this axis so that the camera may be positioned to image the sample S on the stage  20  of the device. 
     The camera  210  is in data communication with a computer  230  by means of a cable  232  or wirelessly using standard protocols such as Bluetooth or WIFI, for example. The computer includes a software program that projects a virtual line over the image of the sample on the screen. This line corresponds to the axis of the diamond indenter  50  of the device  10  to better enable precision cleaving of the sample S. 
     The camera system of the third example would work equally well in conjunction with the first and/or second examples. For brevity, the camera system  200  is described with reference to the second example, however those skilled in the art will appreciate its applicability to any of the examples and the camera system can be readily modified and adapted for use with any of the examples without undue experimentation. 
     The computer  230  can be any Mac, PC, or Unix-based system, laptop, desktop or equivalent, as would be well-appreciated by those of ordinary skill in the art. 
     A base of the camera stand  220  may be coupled to the base ( 12  of  FIG. 1 ) for the device  10  for stability. In equivalent examples the base is not coupled to the device  10 . 
     A stage with X-Y motion (not shown) can be coupled to the base ( 12  of  FIG. 1 ) which can then be coupled to the base of the camera support  220 . X-Y motion enables viewing of a larger area of the sample prior to selecting the cleaving direction. 
       FIG. 21  is a flow diagram showing a method of cleaving a substrate using the devices for cleaving a substrate described above. The method of cleaving a substrate may be accomplished using any of the three previously described examples. For brevity, a method of use is described herein with reference to one of the examples and those skilled in the art will understand that additional steps could be augmented without detracting from the scope of the invention. Conversely, and equally applicable, elements could be eliminated or combined and still not detract from the scope and spirit of the invention. 
     A first step is to clean the stage (block  170 ), especially under the cleaving bar as dust and other debris on the stage can damage the cleave, result in an inaccurate cleave, damage the mechanism, or otherwise waste or make inefficient the process of cleaving a substrate. One possible way to clean the stage is with a fine bristle brush, another way is to blow compressed air across the surface, or clean by equivalent techniques. 
     The cleaving bar is extended to its full down position and the sample is positioned on the stage with its front edge flush against the cleaving bar (block  172 ). This helps roughly positions the sample on the stage. 
     Next the sample is placed on the stage (block  172 ) and positioned manually in front to the indenter, and the scribe guide is set. 
     Manual (or coarse) positioning of the sample is adjusted by putting the area of interest (“AOI”) of the square or rectangular sample, and the knife-edge in approximate alignment. The substrate ( 1005  of  FIG. 4 ) is approximately positioned on the stage with a desired cleave line ( 1002  of  FIG. 4 ) visually lined up with the diamond tip ( 48  of  FIG. 1 ). 
     The diamond tip has previously been positioned somewhere along the edge of the stage, for example to accommodate the size of the sample. If the work piece has an edge perpendicular to the edge that has been aligned against the cleaving bar then the work piece may also be held secure by the scribe guide ( 92  of  FIG. 4 ) with the guide adjuster ( 96  of  FIG. 4 ) secured. The cleave line is now approximately positioned in line with the diamond tip. 
     Next, for systems that do not include a camera system, the spring-loaded indenter ( 40  of  FIG. 1 ) is pushed down by hand until the diamond tip of the indenter is just above the top surface of the sample, but not touching the surface (block  178 ). 
     The diamond tip can now be moved to fine position it over the desired cleave line of the stationary sample on the stage. Turning the knob  24  moves the diamond tip over the desired location of the cleave (block  180 ) on the sample. The sample had been positioned on the stage previously, so that excessive movement of the knob is not necessary to position the tip over the cleave line to achieve a more accurate cleave 
     For systems that include a camera system, a more precise alignment of the cleave can be positioned by using a line drawing feature of the software associated with the camera system (as described above) (block  182 ). The line drawing feature superimposes a visual line on a monitor with a live image of the sample on the stage in focus. Again, the stage drive knob provides precise x-direction alignment of the virtual line relative to the sample. 
     In another example, a laser beam can be projected on the sample (block  184 ) corresponding to the location of the indenter apex. This laser beam system may be incorporated into with the camera system. An advantage of the laser is that the camera is not required to visualize where the cleave would lie on the sample. However, also using the camera allows magnification of the sample and therefore allow a more precise visual and manual aligning of the sample relative to the indenter. 
     With the indenter positioned accurately over the sample, next continued pressure on the indenter results in the indenter pushing into the sample (block  186 ). If the device includes an indenter drive knob, this knob can be turned until the indenter is touching the top of the sample and the sample is now pinched between the indenter and the breaker, or cleaving bar. Next an indent to a desired depth is made by turning an indenter knob a desired amount. 
     Then, a twist of the knob clockwise corresponding to the needed movement for downward travel creates sufficient pressure on the sample to enable smooth operation of the indent. If this indenter drive knob  80  is not included in the system, then the operator uses hand pressure on the indenter bar while manipulating the scribe. 
     Next, the breaker, or cleaving bar is lifted (block  187 ), and the sample is re-positioned for cleaving. With the cleaving bar lifted, the sample is slid under the cleaving bar until it is over the breaking pins (block  192 ). The indentation line that is physically on the sample as a result of the scribe line just described is visually aligned to a reference mark on the back wall. The scribe is positioned on the breaker pin hill. For systems with a camera system, accuracy can be verified by viewing the monitor. 
     Next, the cleaving bar is pushed down against the sample. Downward pressure on the knobs causes the sample to break at the scribe line (block  194 ). Next, lift up the cleaving bar and remove the cleaved sample from the stage (block  196 ). 
     The device  10  of the present invention, in all of its various examples, is well suited for cleaving substrates of most known diameters from about ¼ inches to about 12 inch diameters, but this should not be limiting. However, other sized substrates would work equally well with little or no modification to the components of this invention. 
       FIGS. 21-25  illustrate the process of cleaving a sample that is carried out by the examples of the device  10 . The process includes creating an indentation on a top surface of the sample by applying a downward force along a vertical axis. The vertical axis is perpendicular to the top surface of the sample, and the downward force can align with the vertical axis or be offset +/−45 degrees. Further, the process includes providing a breaking pin and arranging the breaking pin under the sample, coincident to a bottom surface of the sample at a position that is directly opposite from the indentation. The process also includes applying a downward force on the sample wherein the downward force comprises a left-side downward force and right-side downward force, each left-side and right-side downward force arranged on opposite sides of the indentation on the top surface. 
     More specifically,  FIGS. 22-24  depict indenting, and  FIGS. 25-26  depict breaking (or cleaving). From  FIGS. 22-26 , it will be appreciated that the two steps work together to provide a complete and improved cleaving process. Accordingly,  FIGS. 22-23  shows an indentation being created on the top surface of a sample.  FIG. 24  illustrates that this indentation can be created at 90 degrees+/−45 degrees tilt from the vertical axis. Then, with the indentation complete from  FIGS. 22-25 , as appropriate, the cleaving (or breaking) process can begin.  FIGS. 25-26  show a downward directed applied force pushing against the top surface of the sample. The downward force is split to the left and right sides of the indentation. And, an opposite resisting force is applied by the breaking pin, which touches the bottom surface of the sample. As the downward force increases, and because of the indentation on the top surface, the sample yields at the indentation and a clean break or cleave is obtained. It will be appreciated from these figures that the indentation and bottom breaking pin are aligned in a common vertical axis. 
     Further, this process contemplates providing a knife or indenter having a diamond tip and enabling the indenter to adjust up to +/−45 degrees from perpendicular, arranging the indenter on the vertical axis and enabling the indenter to be operable from a first retracted position to a second extended position wherein the extended position causes the indenter to contact the top surface of the sample. 
     Another contemplated process includes either cleaving or indenting or both on one machine or on two separate machines. 
     Another contemplated process includes a first machine for indenting a sample and a second machine for cleaving the sample. The operations of cleaving and indenting can then be done independently and one operation would not need the other operation. For example, a machine could indent a sample, but the cleaving of that sample could be done by hand, or by another traditional cleaving device known in the art. 
     Another contemplated process holds the top left and right pins stationary and makes the bottom breaking pin move upward towards the left and right pins. One example is that the entire stage could be operable to move from a retracted, down position to a second upward position that causes the indenter and/or left and right pins to contact the sample, and to continue moving to either indent the sample or to cleave the sample, or both. The relative movement of the breaking pin in relation to the left and right pins, which are positioned on either side of the indentation is desired. However, how the indentation was made, or which pins move, and which direction the pins move, is not as important as the relative motion between these elements. 
     Another contemplated process includes the steps of providing a cleaving device comprising a stage horizontally disposed on a housing body, the stage having a substantially flat top and a means for adjusting horizontally in the x-direction with micron precision; an indenter slideably arranged to be operable along a vertical axis arranged perpendicular to the top of the stage, the indenter slideably mounted to the housing body, the indenter comprising an indenter comprising a diamond tip, the indenter disposed to operate from a first retracted position to a second extended position along the vertical plane; a breaking pin mounted on the housing body under the indenter; and a breaker, or cleaving bar disposed on the housing body and being operable along a vertical axis from a first retracted position to a second contacting position, the breaker, or cleaving bar further including a left side breaker pin arranged on a bottom surface of the breaker, or cleaving bar and a right side breaker pin on the bottom surface wherein the left and right side pins are disposed on opposite sides of the breaker bar relative to the vertical axis; placing the sample on the stage; creating an indentation on a top surface of the sample by applying a downward force along a vertical axis, the axis perpendicular to the top surface of the sample; applying a downward force on the sample wherein the downward force includes a left-side downward force and right-side downward force, each left-side and right-side downward force applied on opposite sides of the indentation on the top surface. 
     This process also includes pushing on the left and right breaker handles simultaneously causing the breaker assembly to move downward, causing the left and right breaker pins to press against the sample; contacting the sample on an underside by the breaking pin; and breaking the sample along the indentation by means of the breaking pin and left and right breaker pins. 
     This process further includes providing a camera system comprising a camera and software resident on a computer, the computer is in signal communication with camera the software adapted to display on the computer an image; and using the camera system to align the sample. 
       FIG. 25  is a cross sectional view of a portion of a sample S having an Indentation I. The indentation is generally “V” shaped, matching that of the scribe  48  that made the indentation. 
     Those skilled in the art will realize that the process sequences described above may be equivalently performed in any order to achieve a desired result. Also, sub-processes may typically be omitted as desired without taking away from the overall functionality of the processes described above.