Patent Publication Number: US-6710612-B2

Title: CSP BGA test socket with insert and method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of application Ser. No. 09/651,860, filed Aug. 30, 2000, now U.S. Pat. No. 6,628,128, issued Sep. 30, 2003, which is a divisional of application Ser. No. 09/234,593, filed Jan. 21, 1999, now U.S. Pat. No. 6,369,595, issued Apr. 9, 2002. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to testing or burn-in sockets and carriers for semiconductor dice and, more specifically, to an apparatus and method for testing dice which use ball grid array (“BGA”) technology, wherein the socket or carrier includes retaining elements, a force system, and a removable die contact insert capable of interfacing with chip scale package (“CSP”) BGA dice received within the carrier. 
     2. State of the Art 
     Semiconductor dice are used in virtually every electronic device because they are versatile and compact. In fact, each year technology advances, allowing for smaller semiconductor dice and resulting in smaller electronic devices. Although semiconductor dice are functional at the time they are created, inherent manufacturing defects, caused by factors such as contamination or process variability, are generally expected in some percentage of dice. Dice with inherent manufacturing defects have shorter lifetimes than dice without such defects and are the largest contributors to early-life failure rates, or “infant mortality.” Semiconductor manufacturers perform test processes to discover dice with these types of inherent manufacturing defects and achieve a lower early-life failure rate, thereby increasing product reliability. 
     “Burn-in” refers to the process of accelerating early-life failures. This is done by cycling a semiconductor die through a series of stresses at raised temperature designed to simulate extreme field conditions to cause failure of the die and remove those dice which would have otherwise failed during early field use. Typical burn-in begins by placing a semiconductor die package into a socket containing probes or terminals for connecting to all electrical inputs and outputs of the die. Testing includes pre-burn-in and post-burn-in testing as well as burn-in testing. Many sockets in the art can be used for many forms of testing and can be either permanently connected to a testing center, or may act as a carrier which is easily moved and attached to one or more different testing centers for various tests. 
     One concern in relation to BGA die test sockets is that the semiconductor die be held in the socket securely enough to maintain a valid testing process through sufficient continuous electrical communication between the socket and the die, yet not so securely held that the die or its electrical connections are damaged. Examples of test sockets which hold dice with leads in place can be found in U.S. Pat. No. 5,504,436 (Okutsu, 1996), and U.S. Pat. No. 5,088,930 (Murphy, 1992). However, these sockets only work to hold the die in place if the electrical connections are of specific given types, namely extending leads. Examples of test sockets which hold BGA dice in place can be found in U.S. Pat. No. 5,531,608 (Abe, 1996), and U.S. Pat. No. 5,518,410 (Masami, 1996). However, none of these conventional sockets can adequately test CSP BGA dice because the array of terminals in a CSP BGA die is significantly smaller and of finer pitch (i.e., spacing between ball centers) than larger scale BGA dice. 
     A second concern, related to the first, is that the test probes used within a socket have sufficient rigidity and conductive capacity to accurately test the die. As semiconductor dice and their conductive elements get smaller, testing of those dice gets more difficult. For example, the test probes used to communicate with the BGA die conductive element array in U.S. Pat. No. 5,518,410 to Masami and U.S. Pat. No. 5,531,608 to Abe, although apparently sufficient for larger scale BGA dice, are not practical for use with CSP BGA dice due to the fine pitch array of minute balls employed. Using known materials and technology to make the probes small enough to distinctly test each conductive element (ball) in the array creates test probes which are insufficiently rigid and/or have insufficient conductive capacity. If test probes are insufficiently rigid, they may bend or break, causing the socket to perform an inaccurate test process. Furthermore, if the test probes have insufficient conductive capacity, they may fail or give inaccurate results. Current technology does not yet permit manufacture of probes small enough to adequately test CSP BGA dice while maintaining the required probe rigidity and conductive capacity. 
     A third concern in relation to test sockets is minimizing the number of automated operations required to load and unload a socket, yet maintain simplicity of socket design. Many conventional sockets and carriers used for testing non-packaged and non-encapsulated dice include multiple parts or parts which must be disassembled to insert or remove a die from the socket or carrier, thus requiring additional automated steps. An example of a carrier with an assembly which must be disassembled to insert or remove a die is disclosed in co-owned U.S. Pat. No. 5,519,332 to Wood et al. (May 21, 1996), herein incorporated by reference. One advantage of using a carrier which must be disassembled, such as that disclosed by Wood et al., is there are fewer moving parts than in carriers which do not require disassembly for use and, thus, less opportunity for mechanical failure. Carriers and sockets in the current art for testing BGA dice which do not require disassembly to insert and remove dice, although they require fewer automated operations, also contain many moving parts. This presents greater opportunity for malfunction and error. 
     A fourth concern in relation to test sockets used in automated test processes is to avoid lids or other socket parts which protrude so far they interfere with the automated processes. Many sockets in the art for testing BGA dice include hinged lids which extend well beyond, or above, the socket and thus may be broken off during automated processes. This result is clearly undesired, as it causes delay, causes possible equipment damage, adds expense for repair, and causes lower die yield. 
     A fifth concern in dealing with BGA dice in test sockets is the build-up of static electricity on the equipment. Current BGA interface die test processes typically include the steps of opening the socket, placing the die within the socket, releasing the die, then closing the socket. Although this may work for larger scale BGA devices which are sufficiently heavy to overcome the static electricity created between the releasing device and the die, it may not work for CSP BGA die test processes. A specific problem experienced more often when testing CSP BGA dice is that static causes the dice to stick to the releasing device instead of remaining in the socket. 
     It would be advantageous to have a die socket and carrier for use with CSP BGA interface dice which holds the die within the socket, has few moving measuring parts, does not require disassembly to insert and remove a die, has a low profile lid and has terminals adequate to accurately interface with and test a CSP BGA die. Furthermore, it would be advantageous to have a method for testing BGA dice which overcomes the static electricity problem. 
     BRIEF SUMMARY OF THE INVENTION 
     According to the present invention, a test socket assembly is disclosed wherein a removable die contact insert, having terminals of sufficient number and disposed to distinctly and accurately interface with and test a CSP BGA die, is disposed within the test socket containing retaining elements and a force system. In general, the invention includes a test socket assembly comprising an electrically insulating base containing a die contact insert and electrically insulating die retaining elements which, in cooperation with the base, apply pressure against the back side of a BGA die to maintain continuous contact between the conductive element array of the die and an array of electrically conductive contacts or terminals on the die contact insert. By operating the retaining elements appropriately, the socket may be opened to insert or remove a BGA die from the socket. 
     In a particular and preferred aspect of the invention, the die contact insert comprises electric terminals in an array in mirrored orientation to that of the conductive elements of a CSP BGA die and is dimensioned such that each conductive element in the array is discretely connected to the socket in electrical communication sufficient to test the die. In one embodiment, the die contact insert is removable and interchangeable. In this way, versatility is afforded for multiple conductive element array configurations using the same socket. In a more simple embodiment, the die contact insert is affixed to or integral with the base. In another embodiment, the electric terminals are wells having electrically conductive material which extend in conductive paths to a peripheral side of the die contact insert. The paths are then adapted to communicate with a testing station or other external station. Such an adaptation allows for mobility and easier connection to the station. In still another embodiment, the electric terminals of the die contact insert employ conductive paths to communicate with a corresponding external interface integral with the base. Such base external interface can then be fit into an existing socket of a burn-in board or otherwise connected to a testing station. 
     In another particular and preferred aspect of the invention, a vertical force is used to assist in maintaining sufficient continuous electrical contact between the BGA die terminals and the die contact insert. In one preferred embodiment, the vertical force is applied by the combination of an insulating plate suspended and urged toward a retaining element by at least one spring. The die contact insert is disposed between the insulating plate and the BGA die such that when the socket is closed, vertical force is exerted toward the BGA die, causing it to remain in substantially continuous electrical contact with the die contact insert. In another preferred embodiment, the retaining element comprises retention tongs which move between open and closed positions by applying or releasing pressure on a tong activating frame. In still another embodiment, the upper member comprises a clamshell lid, spring-loaded latch and resilient foam member. When the clamshell lid is moved into the closed position over a die, the resilient foam member applies downward pressure on the die. Yet another embodiment comprises retention tongs, each having an end affixed to at least one spring urging the retention tong toward the base. Thus, a force is applied from the tongs to any die placed within the socket. The socket is opened and closed by applying pressure on a tong activating frame which moves the retention tongs into an appropriate position. In still yet another embodiment, a low-profile lid is pivotally attached to the insert to open or close the socket and is held closed by a latch. Using a lid allows for a portable robust package which may be transferred between various test processes. Using a low-profile lid, the robust package may be used in automated processes more easily and with less risk that the lid will be broken off. 
     A method for testing CSP BGA dice is also disclosed wherein the static electricity problem experienced in prior art is overcome. According to the method, a BGA die is brought above a vertical compression test socket by a die deposit probe surrounded by a sufficiently rigid sleeve. The sleeve is independently lowered to apply a vertical force to a retaining element activating mechanism, thus opening the socket. The die deposit probe then lowers the die into, and aligned with, the socket containing an insert for accommodating that particular CSP BGA die. Instead of then removing the probe as is currently done in the art, the sleeve is withdrawn to close the socket. With the die held in place, the die deposit probe is then withdrawn. The die is removed by reversing the previous steps. 
     Other features, advantages, and objects of the present invention will become apparent from a consideration of the drawings and ensuing description. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     In the drawings, which depict presently preferred embodiments of the invention and in which like reference numerals refer to like parts in different views: 
     FIG. 1 is a perspective view of an IC socket according to one embodiment of the invention. 
     FIG. 2 is a top view of a die contact insert according to one embodiment of the invention showing a terminal well array and traces extending to peripheral bond pads. 
     FIG. 3 is a sectional view of one embodiment of the die contact insert showing a preferred cross-sectional shape for the wells. 
     FIG. 4 is a sectional view of one embodiment of the socket with portions of the base, tong activating frame, plate and die contact insert removed to expose the die contact insert wells. FIG. 4 also depicts a probe and sleeve with the housing partially removed to show socket operation. 
     FIG. 5 is a view similar to FIG. 4 showing the socket open before a BGA die is deposited. 
     FIG. 6 is a view similar to FIG. 4 showing the socket open after a BGA die is deposited. 
     FIG. 7 is a view similar to FIG. 4 showing the socket closed after depositing a BGA die, but before removing the probe. 
     FIG. 8 is a view similar to FIG. 4 showing the socket closed after depositing a BGA and removing the probe. 
     FIG. 9 is a view similar to FIG. 4, but illustrating a second embodiment of the socket operation. 
     FIG. 10 is a view similar to FIG. 4, but illustrating a second embodiment of the socket open after depositing a BGA die. 
     FIG. 11 is a perspective view of a die carrier insert according to a third embodiment of the present invention. 
     FIG. 12 is a sectional view of the die carrier insert having gull-wing leads disposed in a TSOP socket where a portion of the housing has been removed to show the carrier. 
     FIG. 13 is a sectional view of a die carrier insert according to an embodiment of the invention with a portion of the external casing removed to show an up-loaded spring and pivot rod attached to the rotating lid. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 depicts a preferred test socket  31  according to the invention for use in BGA die test processes. This socket is operated by applying a vertical force or pressure to a tong activating frame  33 , thus compressing the socket  31  and causing retaining elements  35 A and  35 B (embodied here as tongs  35 A and  35 B) to pivot outwardly sufficient to permit a BGA die  37  (see FIG. 4) within the socket  31 . Preferably, socket guides  39 , integral with the tong activating frame  33 , are slidably associated with a base  41  having corresponding guide slots  43  to ensure the tong activating frame  33  and the base  41  are securely aligned during operation to prevent tilting, twisting and jamming of the cooperating components. When pressure is released from the tong activating frame  33 , socket closing springs  45  urge the tong activating frame  33  upward, causing the tongs  35 A and  35 B to pivot inward. 
     Conventional vertical compression IC sockets are well known in the art. Specific examples of the mechanics of vertical compression sockets are described in U.S. Pat. No. 5,364,286 to Matsuoka (1994), and U.S. Pat. No. 5,531,608 to Abe (1996), herein incorporated by reference. No further description is believed to be necessary in regard to the mechanics and operation of conventional vertical compression sockets. While it is contemplated that some conventional vertical compression sockets might be modified to work with the insert the inventors have disclosed, conventional vertical compression sockets still maintain the aforementioned disadvantages. According to the present invention, a die contact insert  47  containing an array of electrical terminal wells  49  resides inside a simplified socket  31  to provide support and a sufficient communication path between a BGA die  37  (see FIG. 4) and the test socket  31 . 
     FIG. 2 depicts a top view of a preferred embodiment of the die contact insert  47  containing the array of terminal wells  49 . The die contact insert  47  with its array of terminal wells  49  can be manufactured as small as is needed from silicon or ceramic using IC fabrication techniques known in the art. The terminal wells  49  each preferably have an opening  51  wider than the well bottom  53  to ensure contact when a conductive element configured as a ball  55  (see FIG. 4) from a BGA die  37  is placed in the terminal well  49  and accommodate some variance. This results in a terminal well  49  having a cross-section with a trapezoidal shape  61  (see FIG.  3 ). A trapezoidal cross-section is achieved preferably with an inverted truncated conical or inverted truncated pyramidal shape. Although it is preferred, a trapezoidal cross-section is not required for accurate testing. Other cross-sectional shapes such as a square, half circle, rectangle, or other shapes which allow the balls  55  (see FIG. 4) of the BGA die  37  (see FIG. 4) to contact a conductive surface of the terminal well  49  are sufficient. The dimensions of each terminal well  49  and the spacing (pitch) between each terminal well  49  are respectively dependent upon the dimensions of the balls  55  used and the spacing (pitch) of the balls  55  on the BGA die  37 . No single dimension or array spacing (pitch) is sufficient for every variety of BGA die arrangement. However, for any given BGA die arrangement, one of ordinary skill in the art may easily calculate the necessary dimensions and spacing (pitch) for the terminal well array  49 . By using IC fabrication techniques, each terminal well  49  can be manufactured for electrical communication with the socket  31 . One way this may be accomplished is by lining each terminal well  49  with a conductive material  69  (see FIG. 3) such as a metal. Such techniques are well known in the art. 
     As should be clear from the above description, by using IC fabrication techniques well known in the art, the die contact insert  47  can be manufactured with many different forms of external contacts and interfaces. By way of example only, depending on the type of contact or interface needed for a given socket  31 , the die contact insert  47  can be manufactured simply to have aluminum traces  59  extending to bond pads  63 , as shown in FIG. 2, which can then be wire bonded out to conductors carried on the socket body, or have pins  65  receivable in a standard socket, as shown in FIG. 3, to a lead frame  67  employing J-leads or gull wings, as shown in FIG. 12, or to a larger BGA interface or adaptor board for connection to a socket made for another device. 
     FIGS. 4-8 depict the operation of one preferred embodiment of the invention. According to this embodiment, an IC test socket  31  is manufactured for use with CSP BGA dice  37  using a die contact insert  47 . The die contact insert  47  is supported from its underside by an electrically insulating plate  71  borne by at least one and preferably a plurality of plate support springs  73  held in place by wrapping each spring around opposing, aligned spring nodes  75  located on the bottom of the electrically insulating plate  71  and on the inside of the base  41  directly below the plate spring nodes  75 . During operation, a probe  77  carrying a CSP BGA die  37  and surrounded by a probe sleeve  79  is brought above an empty test socket  31  (FIG.  4 ). The BGA die  37  is preferably held to the probe tip  81  by suction applied through an aperture  83  in the probe tip  81 , but other means known in the art are also adequate. For example, multiple probes having multiple probe tips comprising vacuum quills may alternatively be used. Once the probe  77  and surrounding probe sleeve  79  are directly above the socket  31 , the probe sleeve  79 , which is sufficiently rigid and of sufficient dimensions to contact the tong activating frame  33  and compress the socket  31 , applies pressure to the tong activating frame  33  to compress the socket  31  and open the tongs  35 A and  35 B (FIG.  5 ). For reliable operation, the probe sleeve  79  of the probe  77  carrying the CSP BGA die  37  preferably extends beyond the BGA die  37  to prevent the die  37  from being knocked loose from the probe  77  or damaged while the socket  31  is being opened. Furthermore, the dimensions of the tongs  35 A and  35 B, although not particularly significant to the operation of the socket  31 , are selected so as to not interfere with the probe  77 , die  37 , or probe sleeve  79  during operation of the socket  31 . 
     Once the socket  31  is compressed and open, the probe  77 , which moves independently of the probe sleeve  79 , lowers a CSP BGA die  37  into the socket  31  so that the array of balls  55  aligns with the mirrored array of terminal wells  49  on the die contact insert  47  (FIG.  6 ). Because the plate support springs  73  urge the electrically insulating plate  71  upward, preferably with enough force that the die  37  in a closed socket  31  is pressed firmly between the tongs  35 A and  35 B and the die contact insert  47 , the probe  77  preferably applies pressure to the die  37  once in the socket  31  to sufficiently depress the plate support springs  73  for the tongs  35 A and  35 B to close over the die  37 . To avoid damage to the plate support springs  73  or other elements of the socket by establishing a limit for the probe&#39;s  77  extension into the socket, plate stops  85  are preferable. 
     After CSP BGA die  37  is securely seated on the die contact insert  47 , but before the probe  77  is withdrawn, the probe sleeve  79  is withdrawn and the closing springs  45  urge the tong activating frame  33  into its rest position. This causes the tongs  35 A and  35 B to pivot back to their position above the BGA die  37  (FIG.  7 ). The probe  77  is then withdrawn, releasing the die  37  (FIG.  8 ). With the plate support springs  73  urging the plate  71  and die contact insert  47  toward the die balls  55  and the tongs  35 A and  35 B exerting equal, opposite force against the die substrate  87 , the die balls  55  are preferably held against the terminal wells  49  in substantially continuous electrical communication throughout the test processes. Also, by closing the tongs  35 A and  35 B before removing the probe  77 , any static electric charge built up between the probe  77  and the die substrate  87  is overcome when the probe  77  is withdrawn; the die  37  remains in the socket  31 . 
     FIGS. 9-10 illustrate a second embodiment of the invention to show that although it is preferable to have force applied within the socket  31  to hold the die balls  55  against the terminal wells  49  for sufficiently continuous electrical communication throughout test processes, such pressure need not come solely from plate support springs  73  (see FIG. 8) urging the die contact insert  47  toward the tongs  35 A and  35 B. At least one other option is to attach coiled tong springs  89  in tension to the tongs  35 A and  35 B at a point on each of the tongs  35 A and  35 B such that without any lateral support, such as provided by tong activating frame  33  in FIG. 9, the tongs  35 A and  35 B would rotate away from the die  37 . Such coiled tong springs  89  can thereby pull the tongs  35 A and  35 B against the die substrate  87  to force the die balls  55  into substantially continuous electrical contact with the terminal wells  49  when the socket is closed. As shown in FIG. 10, when the socket  31  is compressed, the tong activating frame  33 , which moves independently of the tongs  35 A and  35 B, forces the tongs  35 A and  35 B upward contrary to the tension provided by the coiled tong springs  89 . Due to the manner in which the coiled tong springs  89  are attached to the tongs  35 A and  35 B, the tongs rotate away from the die when tong activating frame  33  reaches a point in relation to the tongs  35 A and  35 B where lateral support for the tongs  35 A and  35 B is no longer provided. When the pressure on the socket  31  is released, the tongs  35 A and  35 B are pulled back down into the socket  31 , are again given lateral support by the tong activating frame  33 , rotate back toward the die  37 , and again apply pressure to the die  37 . 
     FIGS. 11-12 depict a third embodiment of the invention wherein a die contact insert  47  for use in testing CSP BGA die  37 , using existing larger-scale sockets, contains a force mechanism  91  and lid  93  within the die contact insert  47 . According to this embodiment, a die contact insert substrate  95 , manufactured using IC fabrication techniques, is disclosed wherein the die contact insert  47  also includes a clamshell lid  93  and spring-loaded latch  97 , rotationally spring-loaded so as to close when released, for holding a CSP BGA die  37  in place for easy transfer of this die contact insert  47  from one test station to another. A probe opening  99  is included in the lid  93  so the lid  93 , like the tongs  35 A and  35 B in previous embodiments, can be closed before withdrawing the probe  77  (not shown) to overcome any static electricity built up between the probe  77  and the die  37 . The clamshell lid  93  used in this embodiment also comprises a resilient force system such as springy foam force mechanism  91  (e.g. an air-filled elastomer), which applies pressure to secure the CSP BGA die balls  55  (not shown, see FIG. 9) against the array of terminal wells  49  (not shown, see FIG. 9) exposed on the upper surface of the die contact insert substrate  95 . In the present embodiment, a die contact insert lid adaptor  101  is used to attach the clamshell lid  93  and spring loaded latch  97  to the die contact insert substrate  95 . As can be seen in FIG. 11, the die contact insert lid adaptor  101  can also be used to provide additional support and protection for the BGA die  37  by extending the die contact insert lid adaptor  101  across the die contact insert substrate  95 , leaving an aperture  103  in which to insert the BGA die  37 . As will be obvious from the discussion herein, the die contact insert  47  can be manufactured having the terminal wells  49  contained within the die contact insert substrate  95 , or an additional removable die contact insert can be created and placed upon the die contact insert substrate  95  for additional flexibility of design and application. 
     Thus, an appropriately sized and adapted die contact insert  47  can be placed in an existing conventional socket  31 . FIG. 12 depicts a die contact insert  47  according to the embodiment described in relation to FIG. 11, but having a lead frame  67  and gull-wing leads  67  and being deposited in a conventional TSOP socket  31 . The TSOP socket  31  depicted in FIG. 12 includes a socket activating mechanism  107 , a socket base  41 , and die contact leads  104  in electrical communication with external pins  105 . By using a die contact insert  47  which comprises a lid  93  and force mechanism  91 , the die contact insert  47  and BGA die  37  can more easily be transferred between pre-burn-in, burn-in, and post burn-in test processes using existing equipment and processes. The die contact insert  47  further allows CSP BGA dice  37  to be tested reliably. 
     FIG. 13 depicts a fourth embodiment of the invention wherein a die contact insert  47  for use in testing CSP BGA die  37  using existing sockets is also used as a carrier for a CSP BGA die  37  throughout the various stages of testing. According to the embodiments shown, a die contact insert substrate  95  is manufactured using IC fabrication techniques. To such substrate  95 , a rotating lid  109  and latch  115  are attached to allow a CSP BGA die to be deposited onto and removed from the die contact insert  47  (not shown, see FIG.  12 ). As will be clear to one of ordinary skill in the art, various forms of rotating lids  109 , latches  115 , and external pins  65  may be substituted for those depicted in the embodiment of FIG. 13 without departing from the nature of the invention. Preferably, the pivot  111  includes an up-loaded pivot spring  123  to urge the lid  109  upward above the spring-loaded latches  115  and stop upward movement with a pivot spring stop  125 . 
     It is contemplated that the various elements of this invention are not restricted to any particular size or shape. For example, although most conventional sockets in the industry are square or rectangular in shape, suggesting a square or rectangular shaped insert would be most appropriate, it is contemplated that such inserts need not be square or rectangular, or of similar size to currently known BGA dice. An insert need only be of a size sufficient to be deposited in a given socket. The terminal wells, although preferably wells which extend below the surface of the insert lined with aluminum, copper or other conductive substance such as metal, can also be flat pads made of similar substances which rest on the surface of the insert, provided the BGA die is sufficiently held in place in alignment over the pads by the tongs, or by some other retaining element or guide. 
     It is also contemplated that the various interfaces between the insert and different sockets are not restricted to a particular method. For example, electronic communication between an insert and a semiconductor socket can be accomplished using various interfaces including, but not limited to, pins, leads, BGAs, bond pads with wiring, and direct wiring. It is also contemplated that such an insert may be removable, like the embodiments shown, or fixed to the socket by adhesive or other means. Although it is contemplated that this invention will be of primary benefit to the art by providing a device and method to reliably test CSP BGA dice, it is intended that this device may also apply to testing large pitch BGA dice or other dice for adapting a socket to test a different size, interface, or type of die. 
     As will be clear to one of ordinary skill in the art, one general advantage of using an insert within a socket is the ability to adapt existing sockets for use in testing BGA dice, and testing BGA dice with varying pitch, ball dimensions and array configurations using the same socket. As will also be clear to one of ordinary skill in the art, an advantage of using an insert manufactured of silicon or ceramic is the ability to create a durable array of rigid contact terminals of any desired shape or electronic property using IC fabrication techniques which can withstand the rigid testing processes applied to semiconductor dice and provide a compatible coefficient of thermal expansion (CTE) to the die material. Another advantage is the ability to create a dense array of precise wells for use with CSP BGA dice where other types of manufacturing techniques are inadequate. Using an insert such as the ones described here, a CSP BGA die can be adapted for use with standard board pitch, thus overcoming previously experienced testing problems. 
     Although the invention has been described with regard to certain preferred embodiments, the scope of the invention is not limited by these embodiments and is to be defined by the appended claims.