Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to handling equipment for semiconductor and integrated circuit (IC) devices or semiconductor devices, such as different types of semiconductor die used as microprocessors, memory devices, etc., and the components thereof. More particularly the present invention relates to movement control and singulation of semiconductor devices during a manufacturing or testing process. 
     2. State of the Art 
     In the manufacture and testing of semiconductor devices, such as bare semiconductor die or packaged semiconductor die, the semiconductor devices, being either packaged or bare semiconductor die, are transferred through various locations and experience extensive handling. In performing specific tests or particular manufacturing operations, it is often required to separate a single semiconductor device from a plurality of similar semiconductor devices. This act of separation can and may be typically referred to as “singulation”. The singulation of a semiconductor device may be accomplished by various means. However, singulation is generally accomplished by implementing an actuating member to stop, advance, or otherwise manipulate a. semiconductor device in some manner with respect to one or more adjacent semiconductor devices. The actuating member is often one or more stop members in the form of pins, rods, cams or lever arms motivated by a pneumatic cylinder. In some alternative designs a solenoid or hydraulic cylinder may be employed. 
     Singulation for semiconductor die marking is one example of isolating a semiconductor device during the manufacturing process. In processing semiconductor devices for semiconductor die marking a plurality of semiconductor devices may be fed to a die marking station by placing them on an inclined track or pathway and feeding them toward the semiconductor die marking station in a serial fashion. Once an semiconductor device enters into a predetermine position on the track an actuation member, such as a pneumatic cylinder, may then contact the semiconductor device to hold it in a fixed position on the track, or alternatively the cylinder may move the semiconductor device to a new position and then hold it in place. Once the marking operation has taken place, the cylinder retracts and releases the semiconductor device for further processing, testing or packaging as may be required. 
     While processing semiconductor devices in such a manner is typically reliable, there are certain inefficiencies associated with such a method. For example, when using mechanical type cylinders, whether they be pneumatic, hydraulic or a solenoid, damage to the individual semiconductor devices is not only a possibility, it is at times a reality. The force of such actuators often mars or leaves marks on the surface of a device and may even cause functional or operational damage in certain instances. Also, in attempting to achieve greater efficiency, the cycle time of such mechanical devices may be increased which results in greater likelihood of damage due to the rapid deployment and impact with the semiconductor IC device or component. Additionally, such actuators require careful positioning such that contact, and thus likely damage, is not made with conductive elements of the semiconductor device. Direct and abrupt contact with the conductive elements would likely result in damage thereto possibly rendering the device inoperable. For this reason, actuators are typically positioned to avoid contact with the conductive balls or bumps on a ball grid array (BGA) type device. 
     Furthermore, pneumatic type cylinders and similar actuators require a certain amount of time to cycle through engagement and retraction, being limited by the high mass of the moving components. Thus, it becomes difficult to improve cyclical times in existing systems even if potential damage from impact of the actuators could be reduced. 
     In light of the shortcomings of the art, it would be advantageous to provide an apparatus and method for handling and singulating semiconductor devices, or semiconductor device components, which may assist in improving cyclical time of such singulation. It would also be advantageous to provide an apparatus and method which reduces or eliminates damage to the processed devices or components during singulation. Such an apparatus or method may advantageously be utilized in conjunction with various phases or aspects of semiconductor device production including both manufacturing and testing. Additionally, it would be advantageous to provide such an apparatus or method with the ability to contact conductive elements of the semiconductor devices without the risk of damage thereto. 
     SUMMARY OF THE INVENTION 
     In accordance with one aspect of the invention an apparatus for singulation of semiconductor devices or components thereof is provided. The apparatus includes two plates each having an opening passing therethrough. A flexible membrane is disposed between the two plates with the opening of each plate being substantially aligned with the other. The flexible membrane is configured to receive an applied fluid pressure adjacent the opening in the first plate and to extend outwardly through the opening of the second plate. The flexible membrane is also configured to contact and immobilize a semiconductor device moving adjacent the flexible membrane upon outward extension through the opening of the second plate. 
     The flexible membrane of the singulating apparatus may be formed of latex, rubber or another suitable material conducive to contacting an semiconductor device without marking or causing physical damage to the device. Use of the flexible material allows the apparatus to contact virtually any surface of the semiconductor device including conductive elements, such as the balls or bumps of a BGA type semiconductor device. The apparatus may also include additional openings to allow for the same membrane, or a separate membrane, to contact the same semiconductor device at a different surface location, to separate the first semiconductor device from a second semiconductor device, or to contact a second semiconductor device. Such a configuration may also be employed such that one flexible membrane contacts and immobilizes an semiconductor device or component while a second flexible membrane subsequently contacts the semiconductor device or component in such a manner so as to reposition it. 
     In accordance with another aspect of the invention, an apparatus is provided for singulating semiconductor components, such as, for example, die or lead frames. The apparatus includes a flexible membrane which is configured to receive an applied fluid pressure on a surface of the membrane such that it expands and contacts an semiconductor device moving adjacent to the membrane. The membrane serves to temporarily immobilize the semiconductor device component for a predetermined manufacturing or testing operation. As described above, the apparatus may be configured with multiple flexible membranes. 
     In accordance with another aspect of the present invention, an automated semiconductor device handler is provided. The handler includes an input location for receiving a plurality of semiconductor devices. A pathway, such as a gravity fed track, carries the semiconductor devices as they are advanced from the input location. A flexible membrane is located adjacent the pathway and is configured to receive an applied fluid pressure on a surface of the membrane such that the membrane extends toward and contacts an semiconductor device traveling along the pathway. As with the other aspects of the present invention, various features or techniques may be incorporated with the automated handler for further enhancement, or alternative implementation. For example, the handler may be coupled with a testing station wherein the flexible membrane contacts and immobilizes a semiconductor device in conjunction with the testing of the device. Similarly the handler might be used in conjunction with various manufacturing processes. 
     In accordance with yet another aspect of the present invention, a method of singulating semiconductor devices is provided. In accordance with the method, a plurality of semiconductor devices are advanced along a predetermined path. A flexible membrane is provided at a location adjacent the predetermined path in anticipation of singulating the semiconductor devices. A fluid pressure is applied to a surface of the membrane to effect an extension or expansion of the membrane towards the path. Upon proper extension or expansion of the membrane, a semiconductor device is contacted and immobilized thereby. The method may further include providing additional membranes. The additional membranes may be operated similarly to that described above for various purposes including physical separation of two or more devices. 
     In accordance with yet another aspect of the present invention, a method of testing semiconductor devices is provided. According to the method a plurality of semiconductor devices are advanced along a predetermined path. A flexible membrane is provided at a location adjacent the predetermined path in anticipation of singulating the semiconductor devices. A fluid pressure is applied to a surface of the membrane to effect an extension or expansion of the membrane towards the path. Upon proper extension or expansion of the membrane, a semiconductor device is contacted and immobilized such that the semiconductor device may be subjected to a predetermined test. The fluid pressure is released from the membrane allowing the membrane to retract from and release the semiconductor device in preparation of receiving and testing an additional device. 
     In accordance with yet another aspect of the present invention, a method of manufacturing a semiconductor device is provided. According to the presently considered method, a plurality of semiconductor devices are advanced along a predetermined path. A flexible membrane is provided at a location adjacent the predetermined path in anticipation of singulating the semiconductor devices. A fluid pressure is applied to a surface of the membrane to effect an extension or expansion of the membrane towards the path. Upon proper extension or expansion of the membrane, a semiconductor device is contacted and immobilized such that the semiconductor device may be subjected to a predetermined manufacturing operation. The fluid pressure is released from the membrane allowing the membrane to retract from and release the semiconductor device in preparation of receiving and performing the manufacturing operation to an additional device. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     The foregoing and other advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which: 
     FIGS. 1A-1C show partial sectional views of one embodiment of the present invention during various phases of engagement with an IC device 
     FIGS. 2A and 2B show partial sectional views of an alternative embodiment of the present invention; 
     FIGS. 3A and 3B show an elevational view of an alternative embodiment of the present invention; 
     FIGS. 4A-4C show an elevational view of singulating mechanism according to one aspect of the present invention; and 
     FIGS. 5A and 5B show partial sectional views of an alternative embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to drawing FIGS. 1A through 1C, an apparatus  10  for singulating or controlling the movement of an integrated circuit (IC) device or semiconductor device  12  is shown. While the semiconductor device  12  is depicted as a ball grid array (BGA) type semiconductor device, the present invention is compatible with numerous types of semiconductor devices as well as semiconductor device components utilized to manufacture the resulting semiconductor device. The apparatus  10  includes a body  14  which is shown in the form of a plate. A first opening  16  is formed in the body  14  and is communicative with a second opening  18  or cavity. The first opening  16  is configured to be coupled with a fluid pressure source such as, for example, a pneumatic or hydraulic supply. The opening  16  thus may include threads or may be otherwise adapted for various fittings or connections to the fluid pressure source as are known to those of ordinary skill in the art. The second opening  18  has a flexible membrane  20  sealingly coupled thereto. Illustrated in drawing FIG. 1A is the flexible membrane  20  in a relaxed and disengaged position. The flexible membrane  20  remains in the disengaged position until a fluid pressure is supplied to the second opening or cavity  18  via the first opening  16 . Upon introduction of a fluid pressure into the cavity  18 , a pressure builds against the interior surface of the flexible membrane  20  until a sufficient amount of pressure causes the flexible membrane  20  to expand outwardly from the cavity  18  and towards the semiconductor device  12 . Ultimately, the flexible membrane  20  contacts the semiconductor device  12  as shown in drawing FIG. 1B and, upon application of sufficient fluid pressure, immobilizes the semiconductor device  12  by pressing it against an opposing surface  22  such as a track or pathway adjacent the apparatus  10 . 
     Referring to drawing FIG. 1C, the apparatus  10  is shown with the flexible membrane  20  expanded or actuated and with the semiconductor device  12  shown in an alternative orientation. The semiconductor device  12  is oriented with the conductive elements  24 , in this case the conductive bumps or balls, exposed to the flexible membrane  20 . Thus the flexible membrane  20  actually contacts the conductive elements  24  while pressing the semiconductor device  12  and holding it against the opposing surface  22 . The use of a flexible membrane  20  in contacting and immobilizing a semiconductor device  12  allows for sufficient stopping and holding power in controlling the movement of the semiconductor device  12 , while minimizing, if not eliminating, the risk of damage to the semiconductor device  12 . Such an apparatus  10  allows for various orientations of the semiconductor device  12  regarding its relative position with respect to the flexible membrane  20 . Additionally, the apparatus  10  prevents damage even during rapid deployment of the flexible membrane  20  since the flexible membrane will conform to the surface of the semiconductor device  12  with which it makes contact. 
     The flexible membrane  20  shown in the above described embodiments, as well as those discussed below herein, may be formed of a latex material. Latex exhibits desirable properties of durability and a high degree of elasticity. However, other flexible materials such as various polymers and rubbers may be suitable for use in the presently described invention. Where the apparatus  10  may be utilized in areas of high temperature, such as, for example, in conjunction with burn-in testing of a semiconductor die or an semiconductor device, it may be desirable to form the flexible membrane  20  from a silicone based material in order to avoid premature deterioration of the membrane  20 . 
     Referring to drawing FIGS. 2A and 2B an alternative embodiment of the present invention is shown. An apparatus  30  is shown for singulating or controlling the movement of a semiconductor device (not shown). The apparatus  30  includes a first plate  32  having a first and second opening  34  and  36  therethrough. The openings  34  and  36  are configured to be coupled with a fluid pressure source and thus may be adapted to receive various fittings or couplings therein. A second plate  38  also includes a first and second opening  40  and  42  therethrough which shall be referred to as apertures for sake of clarity. The apertures  40  and  42  are generally aligned with the openings  34  and  36  respectively. A first and a second flexible membrane  44  and  46  are sandwiched between the two plates  32  and  38  and a portion of each is exposed to the openings  34  and  36  as well as the apertures  40  and  42  respectively. It is noted that while the flexible membranes  44  and  46  are designated as individual components, they are actually shown to be formed of single sheet or film of material  48 . Such designation of separate membranes  44  and  46  is used for convenience in describing the individual components, but also indicates that separate and individual sheets or films of material could be placed between the two plates  32  and  38  so long as the material was oriented in a sealed manner between the openings  34  and  36  and the apertures  40  and  42  to properly form the membranes  44  and  46  respectively. Likewise, while both plates  32  and  38  are shown as unitary members, either may be formed of multiple components. For example, the bottom plate  38  may be formed of separate flange members, each having an opening therethrough, and each serving to seal the flexible membrane adjacent its respective opening. 
     As shown in drawing FIG. 2B, the flexible membranes  44  and  46  expand outwardly upon introduction of a fluid pressure via the openings  34  and  36 . Such outward expansion allows the membranes to extend toward a semiconductor device (not shown) located adjacent the apertures  40  and  42  and contact the semiconductor device to immobilize it for a predetermined purpose similar as described above. 
     The two openings  34  and  36  may be connected to a common fluid source such that they operate simultaneously and synchronously, or, in the alternative, the openings may have independent controls associated with the introduction of a fluid pressure to each. Thus, each membrane, if so desired may be operated independently of the other to assist in singulating and controlling the movement of one or more of a plurality of semiconductor devices. The embodiment illustrated in drawing FIGS. 2A and 2B provides the advantage of simplified maintenance. For example, if one of the flexible membranes  40  or  42  should rupture or leak at any time, replacement is effected rather simply by disassembling the two plates  32  and  38  and replacing the membrane. 
     Referring to drawing FIGS. 3A and 3B, another alternative embodiment of an apparatus  60  for singulating semiconductor devices or semiconductor device components is depicted. The apparatus includes a bladder  62  formed of a flexible material such as the flexible membranes discussed above. The bladder  62  is held, at one end, by a clamping mechanism  64 . The clamping mechanism  64  serves to hold one end of the bladder in fixed position, and may cause the bladder  62  to be in a relatively low state or tension when in a disengaged or empty status as depicted in drawing  3 A. The clamping mechanism  64  may also be used to seal an open end of the bladder  62  depending on the particular construction of the bladder  62 . The second end of the bladder  62  is sealingly connected with a coupling or fitting  66  to accommodate the introduction of a fluid pressure into the interior of the bladder  62 . The coupling  66  is connected to a fluid pressure source (not shown) via tubing  68  or a similarly adequate structure. Upon introduction of fluid pressure into the bladder  62  via the tubing  68  and coupling  66 , the bladder  62  expands outwardly as shown in drawing FIG.  3 B. The bladder  68  expands sufficiently to contact and immobilize a semiconductor device, or a semiconductor device component passing thereby. The use of the apparatus  60  shown in drawing FIGS. 3A and 3B allows for installation in areas where space is limited, or where a compact design is required. Such a design might allow for easier modification or retrofit or existing machinery and device handlers. 
     Referring now to drawing FIGS. 4A through 4C a portion of an automated handler  80  is shown wherein flexible membranes or bladders, similar to those described above, are employed. The handler  80  includes an input location  82 , such as a hopper or magazine, for loading a plurality of semiconductor devices  84 . The semiconductor devices  84  dispense serially onto an inclined track  86  which feeds the semiconductor devices to a singulation device  88  such as by means of gravity. As the semiconductor devices  84  pass along the track  86  adjacent the singulation device  88 , a flexible membrane or bladder  90 , similar to that described above, is actuated such that it contacts and immobilizes the semiconductor device  84 ′ furthest down the track  86  as seen in drawing FIG.  4 A. Immobilization of the semiconductor device  84 ′ adjacent the singulation device  88  also causes all of the upstream semiconductor devices to stop as well. A second flexible membrane or bladder  92  then engages the semiconductor device  84 ″ directly adjacent and upstream from the first immobilized semiconductor device  84 ′ as shown in drawing FIG.  4 B. Thereafter, the first flexible membrane  90  is disengaged allowing the first semiconductor device  84 ′ to advance while the remaining semiconductor devices  84  are held in place by the immobilization of the second semiconductor device  84 ″ via the second flexible membrane  92 . While stopped by the first flexible membrane  90 , the first semiconductor device  84 ′ may be subjected to a testing or manufacturing process. Or alternatively, following the release of the first semiconductor device  84 ′ it may be stopped by a third flexible membrane (not shown) at a predetermined distance down the track  86  to be subjected to a specified manufacturing or testing process. Subsequent the release of the first semiconductor device  84 ′, the second semiconductor device  84 ″ may be released and advanced until it is contacted and immobilized by the first flexible membrane  90  and the cycle will continue. 
     Referring to drawing FIG. 5A, a singulating apparatus or device  100  is shown in conjunction with a testing device  102 . The singulating device  100  employs a flexible membrane or bladder  104  to singulate a semiconductor device  106  as described above. The semiconductor device  106  is then subjected to a test or a series of tests conducted via the testing device  102 . For example, the testing device might include an apparatus which engages with the plurality of conductive elements  108  through which the internal circuitry may be tested. Alternatively, the testing device  102  may include componentry used to test the integrity of soldered joints. Similarly, other various tests may be performed upon the semiconductor device  106  subsequent singulation as known and understood by those of ordinary skill in the art. 
     Referring to drawing FIG. 5B, the singulation apparatus  100  is shown to be used with a manufacturing or processing apparatus  110 . The semiconductor device  106  is inverted as compared to that shown in drawing FIG.  5 A and the flexible membrane  104  is shown to be contacting a plurality of the conductive elements  108  on the semiconductor device  104 . With the semiconductor device  104  oriented as shown in drawing FIG. 5B, a manufacturing process such as marking or de-marking the semiconductor device  104  may be carried out. For example, the processing device may be a laser marking apparatus used to mark the semiconductor device  104  during singulation. Likewise, similar manufacturing steps may be carried out in a like manner. Also, multiple bladders may be strategically positioned to motivate or reposition a semiconductor device or component into a desired position. 
     It is noted that the various described embodiments may be combined in various forms in implementation, and that such descriptions have been exemplary and should not be considered as limiting. For example, the flexible membrane or bladder of any of the above described embodiments need not contact the major surface of a semiconductor device or component thereof to effect singulation. Rather, such bladders may be used to effect singulation by contacting a minor surface, such as the relatively thin side or edge of a device. Similarly, the bladders may be used to separate a first device from a second device. Additionally, multiple bladders may be used to contact a single device including contact on opposing sides of the device or component. 
     Thus, while the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.

Technology Category: 7