Patent Document

RELATED APPLICATIONS 
   This patent application is a divisional of U.S. patent application Ser. No. 10/642,052, filed Aug. 15, 2003 now U.S. Pat. No. 7,066,314, which derives priority from U.S. Provisional Application No. 60/404,192, filed Aug. 16, 2002. 

   COPYRIGHT NOTICE 
   © 2003 Electro Scientific Industries, Inc. A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. 37 CFR § 1.71(d). 
   TECHNICAL FIELD 
   This invention relates to microelectronic component or “chip” handling equipment and, more particularly, to a transfer belt and a chip carrier employed in a chip termination process. 
   BACKGROUND OF THE INVENTION 
   As computers and related equipment are made with greater capacity for more complex tasks, the internal components, in these computers and other components, have been downsized necessarily so that more and more components can be crowded into the same overall computer container. For example, the capacitor developed by Michael Faraday in the form of a Leyden jar has been reduced in size to that of a grain of salt.  FIGS. 1A and 1B  (generically  FIG. 1 ) show exemplary respective components  10   a  and  10   b  (generically components  10 ). With reference to  FIG. 1A , a typical capacitor component  10   a  is in the form of a rectangular parallelepiped of a length of 0.02 inch (0.51 mm), a width of 0.01 inch (25 mm), and a height of 0.03 inch (0.76 mm), e.g., over 33 of these components placed end to end, would measure almost one inch (25.4 mm). 
   Greater details of the external and internal structure of a typical component are shown in U.S. Pat. No. 5,226,382 (the &#39;382 patent) of Braden. After the components  10  are first manufactured, their electrical contact surfaces at ends  12   a  (or the sides) of component  10   a  are coated with a thin layer of solder paste  14   a  that also covers small adjacent portions of the sides. The solder paste  14   a , also called a “termination,” contains ingredients that upon firing at elevated temperatures render it hard, easy to handle, and easy to reheat for a solder connection to copper strikes on a circuit board. The process of coating and firing components  10  is called a “termination” process.  FIG. 1B  shows multi-element or array component  10   b  that has multiple discrete lines of solder paste  14   b   1 ,  14   b   2 , and  14   b   3  (generically  14   b ) applied across discrete electrical contact surfaces on end  12   b  (or the sides) in contrast to surfaces that can be coated on the entire end  12   a  or on any portion thereof. 
     FIG. 2A  is plan view of a prior art carrier belt  20 , and  FIG. 2B  is a cross-sectional view of a prior art carrier mask  22  that is molded onto carrier belt  20 . With reference to  FIGS. 2A and 2B , a conventional method of high-speed termination employs a continuous metal carrier belt  20  having a plurality of edges  23  that define laterally elongated apertures  24  formed therein that host a like plurality of masks  22  that are molded onto carrier belt  20  from silicon rubber and held by its molded flanges  30 . The components  10  are loaded in vertical orientation in component holes  26  in masks  22  with their respective ends  12  (or sides) exposed above and below masks  22 . The process employs drive spoke wheel holes  28  to advance the chip-loaded belt  20  to a dipper or “dauber” station where carrier belt  20  is slightly deformed to move one end  12  (or side) of components  10  into contact with termination paste and thereafter pass components  10  through an oven to set the paste before applying the paste to the other end  12  (or side) of the components  10  as disclosed in detail in the &#39;382 patent. 
   Belt-based termination systems are commonly used in the passive electronic component industry. The cost of replacing belts  20  is a significant portion of the overall operating cost of belt-based termination systems. Each new type of geometry for components  10  may require differently sized masks to hold them. Manufacturers with a high mix of component geometries may require frequent belt changes. The cost of a new endless belt  20  with newly sized masks  22  is significant, and the downtime encountered in changing and tuning new belts  20  takes away from production time and adversely affects throughput and price. Taking belts  20  on and off for temporary belt substitutions can also damage the belts  20 , making them useless or adversely affecting the quality of the parts processed on them. 
   Alternatively, employing the same mask  22  and belt  20  combination for a variety of component designs and sizes reduces the overall quality of the termination process primarily because sharp-edged components  10  tend to cut, shave, or otherwise fray the holding surfaces of the masks  22 . Once such damage is done, slightly smaller components  10  or those having a slightly altered body shape are generally not held in masks  22  with sufficient force to avoid misalignment or loss of components  10 . Masks  22  will also wear out even if they are used only to hold a single type of component  10 , and neither masks  22  nor belts  20  are inexpensive to replace. 
   Re-masking of a belt  20  with new masks  22  presents its own set of problems. The costs of physically cutting away the old mask makes labor costs high and is a source of physical damage to the typically thin stainless steel belt  20  from an errant knife cut or unintentional creasing. Dissolving away the old mask is possible; however, the solvent and the rubber-solvent solutions are not inexpensive and are candidates for environmental problems in storing and discarding the material. Typically, used belts  20  are discarded. 
   In addition to mask wear issues, typical mask material must be sufficiently elastic to releasably hold components  10 , but such elasticity is nearly incompatible with desired alignment tolerances for holding certain types of components  10 , such as multiple element or array components  10   b , within masks  22  for processing with greater precision and incompatible with increases in the number of rows  30  of holes  26 . 
   Alignment of the belt  20  to processing stations is typically accomplished by aligning the drive holes  28  to the processing station. Unfortunately, this method of alignment necessitates tight alignment tolerances on the drive holes  28 , drive wheels, pulleys, walking beams, and/or other belt translation devices, and processing stations and necessitates labor-consuming alignment of the processing stations to each other. Such alignment requirements increase wear, cost of the equipment, and setup and realignment time, and decrease equipment processing speed and overall throughput. Despite such expensive alignment procedures, components  10   b  often suffer from misalignment of respective pairs of contact pads  16   b   1 ,  16   b   2 , and  16   b   3  (generically  16   b ) of solder paste  14   b  such that components  10   b  cannot be simultaneously functionally and squarely seated in a circuit board. 
   SUMMARY OF THE INVENTION 
   An object of the invention is, therefore, to provide a replaceable component carrier. 
   Another object of the invention is to provide such component carriers that can be independently aligned to one or more processing stations. 
   The present invention employs replaceable component carriers for retaining components in a modular belt during termination and other processes and during transport to and from processing stations. In some embodiments, the carriers are adapted to be snapped into transverse elongated apertures formed in the belt such that the carriers are freely floating in the apertures. Each of such carriers has two or more alignment features, such as spaced-apart conical holes, mated to features, such as tapered pins, in processing stations to temporarily hold the freely floating carrier and its components in a fixed position in the belt during various processes. In some embodiments, the carriers include a more rigid substructure to maintain alignment and process quality and a less rigid, more elastic covering that lines support holes such that they are suitable for receiving and holding the components during the various processes. The shape of the resulting elastic receiving holes can be adapted for receiving a particularly shaped component, and the carriers can quickly and easily be exchanged or replaced whenever differently shaped holes are desired or whenever the receiving holes become too worn to reliably handle components. The carriers can be replaced without removing the belt, thereby reducing the risk of damage to the belt, the cost of replacing the belt, and the operational downtime associated with removing or replacing the belt. 
   Additional objects and advantages of the invention will be apparent from the following detailed description of preferred embodiments thereof, which proceeds with reference to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIGS. 1A and 1B  are isometric views of exemplary electronic components with at least one end coated with a termination paste. 
       FIG. 2A  is plan view of a prior art carrier belt. 
       FIG. 2B  is a cross-sectional view of a prior art carrier portion that is molded onto the carrier belt of  FIG. 2A . 
       FIGS. 3A and 3B  are respective plan and cross-sectional views of an embodiment of a replaceable carrier. 
       FIGS. 4A and 4B  are respective plan and side elevation views of an exemplary removable carrier engaged with a carrier belt. 
       FIG. 4C  is a side elevation view of a removable carrier having an alternative projection engaged with a carrier belt. 
       FIG. 5  is a fragmentary cross sectional view of an embodiment of a removable carrier showing details of an radio-frequency identification tag, an aperture-engagement projection, and mated alignment features between a carrier and a processing station. 
       FIG. 6  is a simplified side elevation view of a processing station alignment fixture positioned over mated alignment features on a removable carrier. 
       FIG. 7  is a simplified fragmentary cross-sectional view of an exemplary carrier attachment system. 
       FIG. 8  is a simplified side elevation view of an exemplary carrier extraction system. 
       FIG. 9A  is a simplified fragmentary plan view of an alternative exemplary carrier attachment system. 
       FIG. 9B  is a simplified fragmentary isometric view of an alternative carrier belt system that can employ an alternative embodiment of a removable carrier. 
       FIG. 10  is a simplified part side elevation and part isometric fragmentary cross-sectional view of an alternative exemplary carrier attachment system. 
       FIG. 11  is a simplified part side elevation and part isometric fragmentary cross-sectional view of an alternative exemplary carrier attachment system that employs securing pins. 
       FIG. 12  is a simplified side elevation cross-sectional view of an alternative exemplary carrier attachment system that employs an alternative type of belt engagement feature. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIGS. 3A and 3B  (generically  FIG. 3 ) are respective plan and cross-sectional views of an embodiment of a replaceable component carrier  40  having multiple rows  42  and columns  44  of component receiving holes  46  for resiliently and firmly holding components  10  during transport to, and processing at, various processing stations, and  FIGS. 4A and 4B  (generically  FIG. 4 ) are respective fragmentary plan and side elevation views of an embodiment of a replaceable component carrier  40  engaged with a carrier belt  72 . With reference to  FIGS. 3 and 4 , a preferred embodiment of carrier  40  comprises a substantially rigid substructure  50  and a resilient or elastomeric coating material or layer  60 . Carrier  40  may alternatively comprise only a single material sufficiently rigid to maintain hole alignment and sufficiently elastic to gently but firmly hold components  10  for processing. 
   Substructure  50  can be made of metal, such as aluminum, magnesium, or steel, or a hard plastic, such as a polyetherimide, with a Vicat softening temperature of above about 200 degrees Celsius, a broad chemical resistivity, and good thermal stability. The material of substructure  50  is preferably adapted to rigidly maintain alignments and distances between components  10 . A preferred embodiment of substructure  50  includes a body  52  that has side walls  54  and end walls  58  and is perforated by rows  42  and columns  44  of support holes  56  that run between substantially parallel and symmetrically positioned recessed areas  62  on opposite sides of the body  52  of substructure  50 . Recessed areas  62  and inside edges  64  of support holes  56  are preferably filled or coated with resilient coating layer  60 , such as with an elastomer like silicon rubber, having an exemplary durometer value of 50 to 80 Shore A to form receiving holes  46  that have a narrower diameter than, and line the internal edges of, support holes  56 . Resilient coating layer  60  is preferably thick enough to reduce the internal dimensions of support holes  56  to desired internal dimensions to capture and hold a component  10  therein with sufficient strength to pass undamaged or unmoved through several processing operations, including termination operations having a paste application step, while being sufficiently pliable or elastic to permit movement of components  10  when directed by a given processing station. The elastomer coating or layer  60  fills in the recessed area  62  about support holes  56  so that the elastomer material at the edges of support holes  56  is not damaged by the insertion of the components into the receiving holes  46 . 
   Substructure  50  and resilient coating layer  60  can be sequentially produced by any number of injection molding processes as are well known to skilled practitioners. Skilled persons will appreciate that substructures  50  can be loaded into belts  72  (as later described), and coating layer  60  can be applied to substructures  50  while they are associated with belts  72 ; or, coating layer  60  can be applied to substructures  50  in a process where they are not supported by a belt  72 . Resilient material  60  can also be made separately and then inserted into substructures  50 . Skilled person will also appreciate that that substructures  50  and/or resilient material  60  can be color coded, such as with colorant additives or processes well-known to skilled practitioners, by sizes, shapes, or patterns of support holes  56  and receiving holes  46  to facilitate sorting or other identification-related processes. 
   Skilled persons will also appreciate that even though support holes  56  and receiving holes  46  are preferably coaxial, neither support holes  56  nor receiving holes  46  need be circular or have similar concentric shapes as shown. For example, support holes  56  may exhibit a diamond-shaped horizontal cross section, while receiving holes  46  may exhibit a square, rectangular, oval, slot or circular horizontal cross section and may be adapted to secure components  10  having specific rectangular parallelepiped or other configurations. Support holes  56  and receiving holes  46  may even have matched or unmatched irregular geometries. 
   Substructure  50  also includes a flange  68  and an engagement feature or projection  70  that cooperate to engage a carrier belt  72  that can be identical to, or different from, the prior art belt  20 . A typical carrier belt  72  is flat, thin, and made from stainless steel, another metal, plastic, or another suitable material and is bordered by a pair of spaced-apart, parallel side edges  76 . Carrier belt  72  typically includes a series of drive holes  78  formed along one or both side edges  76  for engagement with spokes of a drive wheel (not shown) that is used in a typical chip termination machine such as disclosed in the &#39;382 patent. Carrier belt  72  also typically includes a plurality of elongated and parallel carrier-receiving areas or apertures  74  oriented transversely to an elongated axis of carrier belt  72  and lying centrally between side edges  76  and spaced evenly from drive holes  78 , such that belt  72  is symmetrical on either side and from either direction. Apertures  74  preferably have an oval or elliptical perimeter to avoid sharp corners along internal edges  82  of belt  72  that could promote stress cracks, and are generally made by a stamp-cutting process wherein a cutter in the outline of an aperture  74  is brought downward against belt  72  as it passes underneath the cutter. Skilled persons will appreciate that apertures  74  need not be symmetrical or symmetrically positioned, and that apertures  74  can be positioned at angles with respect to side edges  76  of belt  72 . Similarly, the elongated axis of apertures  74  may be oriented to be parallel to the elongated axis of carrier belt  72 , and such apertures  74  could be grouped parallel to each other in sets. 
   The body  52  of carrier  40  is shaped to be similar to, but dimensionally smaller than, aperture  74  such that side walls  54  fit within internal edges  82 . Side walls  54  are preferably adapted to be spaced away from internal edges  82  along one or both sides  84  and/or one or both ends  86  of aperture  74  by a gap  88  of about 0.3 to 2 mm (and preferably about 1 mm), for example, such that when carrier  40  is inserted into aperture  74 , carrier  40  is able to move or “float” within the internal edges  82  of aperture  74 . The shape of body  52  or aperture  74  can be designed to permit symmetrical or asymmetrical gaps along sides  84  and/or ends  86  and can be designed such that the gaps  88  along sides  84  and ends  86  can be the same or different. Exemplary lengths  90  and widths  92  of body  52  are respectively 75 mm and 8 mm, and exemplary lengths  94  and widths  96  of aperture  74  are respectively 76 mm and 9 mm. 
   While most dimensions of body  52  are smaller than the respective dimensions of aperture  74 , the thickness (or height)  100  of carrier  40 , defined by a distance between a top carrier surface  102  and a bottom carrier surface  104 , is preferably greater that the thickness (or height)  106  of belt  72  or internal edges  82  such that top surface  102  of carrier  40  is located above belt  72  and bottom surface  104  of carrier  40  is located below belt  72  when carrier  40  is inserted into aperture  74 . Typical belt heights  106  are about 0.5 mm to about 2 mm, and preferred carrier heights  100  are about 3 mm to about 6 mm. The larger height  100  of carrier  40  facilitates adaptation of a flange  68  that has a top surface that is preferably planar with top surface  102  and extends outwardly from body  52  so that flange  68  overhangs and preferably contacts top surface  108  of belt  72  whenever carrier  40  is positioned within aperture  74 . Flange  68  is preferably attached to or integrated with substructure  50  and made from its same material. Flange  68  is also preferably continuous around the entire perimeter of body  52  and is preferably designed to have a symmetrical overlap  110  of top surface  108  around the perimeter of aperture  74  and/or a symmetrical overhang  98  around body  52 . Skilled persons will appreciate that flange  68  may alternatively be discontinuous and may comprise, for example, numerous “teeth” that overlap top surface  108  along portions of sides  84  and/or ends  86  of aperture  74  or may simply comprise a minimum number of nubs  70   a  ( FIG. 4C ), such as one at each end  86 , sufficient to prevent flange  68  from being pulled through aperture  74 . Flange  68  may alternatively or additionally be designed to have dissimilar amounts of overhang  98   a  and  98   b  (generically  98 ) around body  52  at different positions around the perimeter of aperture  74 , such as in proximity to the sides or ends of body  52 . 
   In an alternative embodiment, belt  72  has height dimension  106  that extends between its respective top and bottom surfaces  108  and  112 , and the carrier-receiving areas have one or more apertures  74  that extend through a vertical side of belt  72  and have height dimensions that are smaller than height dimension  106  of belt  72 , such that body  52  or the entirety of carrier  40  can be inserted through a vertical side of belt  72 . In such an embodiment, flange  68  and/or projection  70  are positioned about the ends of body  52  and may encompass both top and bottom surfaces  102  and  104 , and these belt-engagement features may be replaced with or enhanced by a different type of belt-engagement feature that is generally horizontally positioned with respect to body  52  and that engages carrier attachment points such as holes or protrusions in internal walls or edges  82  of belt  72 . 
   Carrier  40  preferably has a projection  70  that is attached to or integrated with substructure  50  or flange  68  and extends outwardly from body  52 , is preferably made from its same material, and may permit carrier  40  to be “snapped” into aperture  74 . Projection  70  is adapted to rest against bottom surface  112  of belt  72  and cooperates with flange  68  to engage belt  72  at sides  84  and/or ends  86  of aperture  74  to removably secure carrier  40  in aperture  74 . Projection  70  may be continuous around the entire perimeter of body  52  or may be discontinuous and may comprise, for example, one or more “teeth” that overlap bottom surface  112  along portions of sides  84  and/or ends  86  of aperture  74  or may simply comprise a minimum number of nubs  70   a  ( FIG. 4C ), such as one at each end  86 , sufficient to secure carrier  40  in aperture  74 . Projection  70 , if discontinuous, may have the same or different dimensions along different portions of body  52 . 
     FIG. 5  is a simplified fragmentary cross-sectional view of an embodiment of carrier  40  showing details of an exemplary projection  70 , a radio-frequency identification tag (RFID tag)  150 , and mated alignment features  160  and  162  between carrier  40  and a processing station. With reference to  FIGS. 4 and 5 , projection  70  comprises one or more flexible fastener tabs (tabs or tab projections  70 ), and most preferably one at each end  120  of body  52 , that are integrated with substructure  50  and/or flange  68  near the junction between them. Each tab projection  70  preferably has an angled flexible arm  122  that allows generally radial movement  126  such that arm  122  can be pushed inward toward side wall  54  of carrier body  52 , and arm  122  is “spring loaded” to return to about its original position or a position suitable for engaging bottom surface  112  of belt  72 . 
   Arm  122  terminates in a hand  124  with a finger  128  that may be generally parallel to side wall  54  of body  52 . Hand  124  preferably has a projection surface  130  that is generally parallel to bottom surface  132  of flange  68  such that it is adapted to engage bottom surface  112  of belt  72 . Projection surface  130  is spaced apart from bottom surface  132  of flange  68  by a height  136  that is about the same as belt height  106 . Hand  124  preferably also has an angled insertion surface  138  that is adapted to deflect away from the junction between top surface  108  and internal edge  82  to facilitate insertion of carrier  40  into aperture  74 , and finger  128  preferably has a flat release surface  140  that facilitates compression of arm  122  toward body  52  to release carrier  40  from aperture  74 . Skilled persons will appreciate that the dimensions, angles, and other features or surface characteristics of tab projection  70  can be modified to address specific belt or carrier features and to cooperate with specific tools or equipment, such as for inserting or removing carriers  40  from apertures  74 . 
   With reference again to  FIG. 5 , a preferred embodiment of carrier  40  has one or more carrier-information or carrier-identification tags or devices, such as bar codes or RFID tags  150  embedded in an epoxy, silicon rubber, or other material layer  152  within respective recesses  154  in substructure  50 . Carrier-information tags are discussed herein only by way of example to RFID tags  150  and permit products to be identified individually and/or by group characteristics. With respect to carriers  40 , RFID tags  150  can be employed to identify different types of carriers  40 , such as those adapted to hold different types or sizes of components  10 , and to facilitate sorting or other tasks. In particular, RFID tags  150  would permit carriers  40  to be individually tracked, such as for the number of times a carrier  40  has been used, or the insertion force exerted to load or reverse components  10 , and can indicate to a control system that a carrier  40  is becoming worn and needs to be replaced. Carrier-information tags can also be used for typical lifetime tracking of batches of carrier  40 , such that each component need not be individually identified, and carrier-information tags can be used in addition to (or instead of) color coding of substructures  50  and/or resilient material  60 . 
   Since RFID tags  150  are becoming inexpensive, skilled persons will appreciate that it could be advantageous to employ two cooperating or cross-identified RFID tags  150  per carrier  40  that are symmetrically positioned such that the exemplary carrier  40  can be inserted into aperture  74  in either of its two possible orientations and still have an RFID tag  150  in proximity to a single receiver or other sensor or information-gathering device, such as a bar-code reader. RFID tags  150  can be positioned, for example, within flange  68  or body  52 , such as within a special hole within recessed area  62  and embedded in resilient coating material  60 . Skilled persons will appreciate, however, that the positions and numbers of RFID tags  150  within carriers  40  can be adapted to suit the particular sizes and shapes of carriers  40  and the locations of the sensors employed to retrieve the information from the RFID tags  150 . 
     FIG. 6  is a simplified side elevation view of a processing station alignment fixture  164  with a pair of alignment features  162  positioned over alignment features  160  on an exemplary carrier  40 . With reference to  FIGS. 5 and 6 , preferred mated alignment features  160  and  162  are holes and pins. Preferably, alignment holes are positioned in carrier  40  and alignment pins are employed by a processing station, but skilled persons will appreciate that carriers  40  could be adapted to include pins and that processing stations could employ holes. Although alignment features  160  could be positioned in flange  68 , alignment features  160  are preferably positioned on, in, or through body  52  of carrier  40  toward end walls  58 . Alignment features  160  are also preferably positioned through at least part of rigid substructure  50  rather than solely through coating layer  60  to increase their useful life and long-term alignment precision against wear. 
   Each carrier  40  preferably includes at least two symmetrically positioned alignment features  160  to simplify carrier orientation requirements such as for loading carriers  40  into aperture  74 . Alignment features  160  are preferably positioned along a central axis of carrier  40 , but can be positioned at any locations on surfaces  102  or  104 , preferably spaced apart by a large distance. Two or more alignment features  160  also facilitate precise alignment with processing stations and prevent lateral movement of carriers  40  within the plane of belt  72  within gaps  88  between body  52  and internal edges  82  of apertures  74  during sensitive processing operations. Such operation might include, for example, simultaneous application of multiple spaced-apart lines of termination paste across surfaces of array components  10   b.    
   In an exemplary embodiment, each alignment feature  160  is implemented as a coaxial pair of connected conical alignment holes  170  having larger openings with a dimension  172  at surfaces  102  and  104  that narrow along angled walls  174  to a smaller dimension  176  at about a middle height  178  (about half of height  100 ) of carrier  40  to permit carrier  40  to be aligned from either side of surface  108  or  112  of belt  72 . (Typically, components  10  are processed on both ends during a continuous belt revolution before components  10  are removed from carrier  40 .) Dimension  172  is preferably a diameter that is at least about the dimension of total play of body  52  within aperture  74  or at least about two times the dimension of (equal) gaps  88 , plus half of dimension  180  of tip  182  of an alignment pin that is a preferred embodiment of alignment feature  162 . Neither the pin nor the hole need be tapered. 
   In a practical application, alignment fixture  164  can be lowered at a processing station under control of a guide rod  184  or other guide mechanism onto carrier  40  such that tips  182  engage respective alignment holes  170 . However, an alignment fixture  164  could be urged against carrier  40  from below bottom belt surface  112 . Alternatively, belt  72  can be pushed against a stationary alignment fixture  164  at a processing station. Processing stations may include, but are not limited to, carrier loading or unloading stations, component loading or unloading stations, paste applying stations, drying stations, component reversing stations, or carrier tracking stations. 
   Mating alignment features  160  of a carrier  40  floating in aperture  74  with alignment features  162  of processing stations have several advantages over conventional methods of aligning belts to processing stations. Floating carrier alignment permits relaxation of alignment tolerances between different processing stations and between them and belt drive mechanisms because each station aligns to carrier  40  independently. Independent alignment of carriers  40  also reduces torsion and other stresses on belt  72  between processing stations so that belts  72  last longer. Similarly, alignment tolerances of drive holes  78  can be relaxed, and wear at drive holes  78  becomes less significant so belts  72  can maintain a relaxed drive alignment for much longer periods of time, even though many generations of carriers  40  may be replaced. Belts  72  may also bend around pulleys, corners, or other deflection points or at processing stations, while rigid carriers  40  will maintain their shape. The rigid shape and independent alignment of carriers  40  permit component processing characteristics to be better optimized and more precise and permit greater uniformity of processed components  10  within and between batches. Such precise characteristics or uniformity may include, but are not limited to, paste thickness, flatness, and/or alignment or orthogonal seatability. Processed components  10  having greater uniformity reduce downstream production costs and increase reliability. 
   In an alternative embodiments, alignment features  162  of processing stations are substituted with vision-type positioning correction systems, such as those employed in the laser, semiconductor-processing, or other industries. In such embodiments, carrier alignment features  160  take the form of fiducials or other surface features that can be used by the positioning system to achieve very precise and very accurate positioning between processing station equipment and carriers  40  and/or their components  10 . The fiducials could even be placed on the components  10 . In such embodiments, combinations of mated alignment features  160  and  162  could additionally be designed to allow some freedom of movement between carrier processing stations and carriers  40  to provide “rough” alignment that could then be refined by the vision system. 
     FIG. 7  is a simplified fragmentary cross-sectional view of an exemplary carrier attachment or insertion system  190  that employs a supply vehicle, such as a carrier feeding tube  192 , to feed carriers  40  into a carrier feeding chamber  194  where a linear actuator  196  pushes a carrier  40  through or along one or more spring-loaded carrier guides or carrier arm guides  198  that may compress projections  70  or their arms  122  toward body  52  and guide body  52  into aperture  74 . Feeding tube  192  preferably has cross-sectional area dimensions in proximity to feeding chamber  194  to permit only a single carrier  40  to enter feeding chamber  194  at a given time. Skilled persons will appreciate that tube  192  and chamber  194  of carrier attachment system  190  need not be vertical and could be angled or generally horizontal and that other types of feed systems and actuators could be employed. Skilled persons will also appreciate that tube  192  need not limit introduction to chamber  194  to one carrier  40  at a time, and several carriers  40  could be loaded simultaneously with multiple actuators  196  or multiple pronged actuators into respective apertures  74  in belt  72 . 
     FIG. 8  is a simplified side elevation view of an exemplary carrier extraction system  210  that employs actuated clamps  212  to compress flat surfaces  140  of fingers  128  of projection arms  122  toward body  52  of carrier  40  to release surfaces  130  from engagement with surface  112  of belt  72 . Substantially simultaneously or subsequently, actuator  214  pushes bottom surface  104  of carrier  40  to release carrier  40  from engagement with internal edges  82  of aperture  74  of belt  72 . Skilled persons will appreciate that carrier extraction system  210  need not be horizontal and could be angled, generally vertical, or facing downwards so that gravity can assist carrier removal and that other types of actuators could be employed. In an alternative embodiment, actuated clamps  212  are angled inwardly to meet angled insertion surface  138  and actuator  214  is eliminated. 
     FIG. 9A  is a simplified fragmentary cross-sectional view of an alternative exemplary carrier attachment system  190   b  for loading alternative types of replaceable carriers  40   b  onto alternative belts  72   b  having alternative carrier attachment features  220  for association with alternative carriers  40   b , and  FIG. 9B  is a simplified fragmentary isometric view of an alternative belt  72   b  that employs such an alternative embodiment of carrier  40   b . With reference to  FIGS. 9A and 9B  (collectively  FIG. 9 ), belt  72   b  may have a uniform solid thickness including and between drive strips  222  or may only have bracing segments  226  with a smaller height dimension than that of drive strips  222 , or drive strips  222  may be completely distinct and be connected only by, and having spaces  228  between, carriers  40   b , such as shown in  FIG. 9B . For convenience, reference numerals may be used without letter identifiers to refer to parts generically. 
   Carrier attachment features  220  of belts  72   b  may include, but are not limited to, apertures  74   b  between pairs of drive strips  222 , and apertures  74   c  that extend through vertical sides  224  of belts  72   b  or their drive strips  222 . Apertures  74   c  have height dimensions  232  that are smaller than height dimension  106   b  of drive strips  222 , such that body  52   b  or the entirety of carrier  40   b  can be inserted through vertical side  224  of belt  72   b . Apertures  74   c  are about the same size as or slightly larger than respective dimensions of the ends of carriers  40   b , but may have flared openings in one or more dimensions to facilitate entry of carriers  40   b . With reference to  FIG. 9 , which depicts several exemplary embodiments, aperture  74   c  has generally parallel openings at both sides of both drive strips  222 . Aperture  74   c   1  has a flared opening along only side dimensions and only on sides of drive strips  222  that are oriented toward carrier attachment system  190   b . Aperture  74   c   2  has a flared opening along both side and height dimensions and on both sides of drive strips  222  so that drive strips  222  are symmetrical from side to side and top to bottom so that they are easier to install. Skilled persons will appreciate that apertures  74   c  in the remote drive strip need not extend all the way through the second side of belt  72   b , or apertures  74   c  may instead take the form of open-topped troughs that may or may not extend through either side of either drive strip  222 , such that carriers  40   b  may be dropped into a secured position within belt  72   b.    
   Carrier attachment features  220  of belts  72   b  may also include, but are not limited to, bumps, small additional apertures or pits, or other features within or in proximity to apertures  74   b  for engagement with mated engagement features  230 , such as projections, bumps, small additional apertures or pits, or other features on carriers  40   b . Such carrier attachment features may be integrated with the internal side walls of apertures  74   c  as shown, but they may alternatively or additionally be positioned on or within the top and/or bottom surfaces of apertures  74   c . Similarly, mated engagement features  230  can be positioned alternatively or additionally on or within the top and/or bottom surfaces  102  and  104  of carriers  40   b.    
   Alternatively or additionally, carriers  40   b  may include flange  68  and/or projection  70  positioned about the ends of body  52  and may encompass both top and bottom surfaces  102  and  104 . In addition to carrier attachment features  220  and mated engagement features  230  that are integrated respectively with belts  72   b  and carriers  40   b , discrete attachment devices, such as securing pins  240 , may alternatively or additionally be employed to secure carriers  40   b  to belt  72   b.    
   In practice, carrier insertion system  190   b  may employ, for example, processes and equipment similar to that of carrier insertion system  190 , such as carrier feeding tube  192   b , carrier feeding chamber  194   b , linear actuator  196   b , and carrier arm guides  198   b  except that carriers  40   b  would be oriented differently and actuator  196   b  would exert force on a vertical side rather than at the top of carrier  40   b . Extraction can be automatically accomplished with an actuator similar to actuator  196   b.    
     FIG. 10  is a simplified part side elevation and part isometric fragmentary cross-sectional view of an alternative exemplary carrier attachment system  190   b . A major difference between the embodiments in  FIGS. 9 and 10  is the orientation of carriers  40   b  in feeding chambers  194   b . Such orientation can be controlled by adapting the design of feeding tubes  192   b  to present carriers  40   b  to chambers  194   b  in the desired orientation. Skilled persons will also note that belt  72   b  runs generally parallel to carrier attachment system  190   b  toward the insertion point in  FIG. 9 , but belt  72   b  runs generally orthogonal to carrier attachment system  190   b  toward the insertion point in  FIG. 10 . 
     FIG. 11  is a simplified part side elevation and part isometric fragmentary cross sectional view of an alternative exemplary carrier attachment system  190   b  that employs securing pins  240 . Carrier insertion system  190   b  of  FIG. 11  employs similar processes and equipment to that of carrier insertion system  190   b  of  FIG. 10 ; however, carrier insertion system  190   b  of  FIG. 11  additionally employs one or more securing pin insertion systems  250 . Securing pin insertion systems  250  may employ gravity feeds or actuators (not shown) to introduce securing pins  240  through belt pin holes  252  into carrier pin holes  254 . Belt pin holes  252  may be flared toward surface  108  of belt  72   b  and/or carrier pin holes  254  may be flared toward surface  102  of carrier  40   b  to facilitate insertion of securing pins  240  through them. Belt pin holes  252  may or may not have symmetrical openings on the belt faces and may not extend all the way through to the bottom of belt  72   b . Belt pin holes  252  and securing pins  240  may be circular or employ a variety of different shapes matching shapes or mated features. The securing pins  240  can be easily removed with an actuator, particularly in embodiments where belt pin holes  252  extend all the way through belt  72   b.    
     FIG. 12  is a simplified side elevation cross sectional view of an alternative exemplary carrier attachment system  190   b  that employs alternative types of belt attachment features  220  that cooperate with mated engagement features  230  to secure carriers  40   b  to belt  72   b . With reference to  FIG. 12 , belt attachment features  220  include projections with tabs  260 , and mated engagement features  230  comprise receiving apertures that are adapted to receive the projections. In a preferred embodiment, tabs  260  are divergent and reside at the ends of the projections and at a height from belt  72   b  such that they protrude above surface  102  or  104  of carrier  40   b  when it is secured to belt  72   b . The receiving apertures may be flared or take on a variety of shapes as discussed with other features in embodiments previously discussed. 
   Carrier insertion systems  190  and carrier extraction systems  210  may be positioned along a continuous belt loop of other processing stations and may be fully automated to extract and replace carriers  10  in response to information received from RFID tags  150  or from software tracking algorithms in a processing station or machine employing carriers  40 . Apertures  74  can also be individually tagged or otherwise identified or can be known as being between apertures containing identified carriers  40  so that empty apertures  74  can be identified if desirable. 
   In an alternative embodiment, belts  72  contain replaceable belt segments that each include one or more carriers  40  or masks  22 . The belt segments could be held together by removable pins or other known attachment means. The pins can be removed and belt segments containing worn carriers  40  or masks  22  could be easily popped out and replaced. 
   Skilled persons will appreciate with respect to belt-assisted termination or other microcomponent manufacturing processes that components  10  can be seated centrally (neither end  12  of component  10  protruding much, if at all, from receiving holes  46 ), and carriers  40  can be extracted from belt  72  while the carriers  40  are holding the components  10 . The filled carriers  40  could then be inserted into another belt that uses a different speed and/or takes the components  10  through a different process. The filled carriers  40  could alternatively be inserted into a cassette for a particular (bottleneck) process such as paste drying and then reinserted in a belt  72  for second end processing, for example, or the filled carriers  40  could be inserted into a cassette for storage, transport, or sale. 
   It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments of this invention without departing from the underlying principles thereof. The scope of the present invention should, therefore, be determined only by the following claims.

Technology Category: h