Patent Publication Number: US-11639956-B2

Title: Integrated circuit testing apparatus and method

Description:
RELATED CASES 
     This is a divisional application of U.S. patent application Ser. No. 16/795,316 filed on Feb. 19, 2020. The disclosure of that application is expressly incorporated by reference. 
    
    
     FIELD OF INVENTION 
     The present invention pertains generally to test sockets with high frequency test capability and more specifically to a test socket with high current carrying capacity which is suitable for chip. 
     BACKGROUND OF THE INVENTION 
     Manufacturers test integrated circuit devices to ensure that consumers receive devices of the highest quality. Manufacturers utilize a plurality of test apparatus to carry out the testing. A tester generally includes a printed circuit board which includes multiple conductive traces. Each trace is associated with a corresponding function of the test apparatus. 
     A lead, in the case of a leaded device being tested, or a pad, in the case of a nonleaded device being tested, is interconnected to a corresponding trace on the load board. A test set or test socket is used between the device being tested and the load board in order to achieve interconnection. One end of each probe is engaged by either the lead or terminal pad of the device being tested, and the opposite end of the probe engages the trace on the load board. 
     As technology has evolved, the shape, size and electrical properties of probes have evolved by necessity in response to the construction of test sets and load boards and the design of devices to be tested. Signal strength is also a vital consideration when designing a testing device. Maintaining impedance through a conducting portion of a probe interconnecting the integrated circuit lead or terminal pad to its corresponding load board pad at a particular desired level is also desirable. The impedance that is achieved is a function of a number of factors. These include width and length of conduction path, material of which the conductive structure is made, material thickness, etc. 
     The present invention includes a probe which improves the testing function beyond what is achieved with other probes. It takes into consideration the dictates of the prior art and overcomes problems extant therein. Thus, there is clearly a need for an integrated circuit testing apparatus which addresses these issues. 
     SUMMARY OF THE INVENTION 
     A test socket comprising a guide plate with a lower surface engaged with an upper surface of a main test structure, the guide plate further including an upper surface which is parallel to the lower surface and an opening extending through the guide plate, the main test structure includes a body with one or more apertures through the upper surface and one or more probes mounted within the main test structure, the probes including a front end which extends through the apertures for engagement by a lead or terminal pad of a device to be tested, and a tail end which is secured within the main test structure by an elastomeric material. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       For the purpose of illustrating the invention, there is shown in the drawings a form that is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown. 
         FIG.  1    is a side elevation view of one embodiment of an integrated circuit testing apparatus. 
         FIG.  2    is an exploded view of one embodiment of an integrated circuit testing apparatus. 
         FIG.  3    is a side elevation view of one embodiment of an integrated circuit testing apparatus. 
         FIG.  4    is a side elevation view of one embodiment of an integrated circuit testing apparatus. 
         FIG.  5    is a side elevation view of one embodiment of an integrated circuit testing apparatus. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention now will be described more fully hereinafter in the following detailed description of the invention, in which some, but not all embodiments of the invention are described. Indeed, this invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well as the singular forms, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one having ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     In describing the invention, it will be understood that a number of techniques and steps are disclosed. Each of these has individual benefit and each can also be used in conjunction with one or more, or in some cases all, of the other disclosed techniques. Accordingly, for the sake of clarity, this description will refrain from repeating every possible combination of the individual steps in an unnecessary fashion. Nevertheless, the specification and claims should be read with the understanding that such combinations are entirely within the scope of the invention and the claims. 
     The instant invention is an improved integrated circuit testing apparatus and method of using that apparatus. The instant invention includes a test socket  10  comprising a guide plate  15  with a lower surface  20  engaged with an upper surface  50  of a main test structure  45 , the guide plate  15  further including an upper surface  16 , which is parallel to the lower surface  20 , and an opening  19  extending through the guide plate  15 . The main test structure  45  includes a body  47  with one or more apertures  27  through the upper surface  50  and one or more probes  30  mounted within the main test structure  45 . The probes  30  include a front end  31  which extends through the apertures  27  for engagement by a lead  64  or terminal pad of a device  60  to be tested, and a tail end  32  which is secured within the main test structure  45  by an elastomeric material  25 . 
     The instant invention also includes a test socket  10  comprising a guide plate  15  with a lower surface  20  engaged with an upper surface  50  of a main test structure  45 , the guide plate  15  further including an upper surface  16 , which is parallel to the lower surface  20 , and an opening  19  extending through the guide plate  15 . The main test structure  45  includes a body  47  with one or more apertures  27  through the upper surface  50  and one or more probes  30  mounted within the main test structure  45 . The probes  30  include a front end  31  which extends through the apertures  27  for engagement by a lead  64  or terminal pad of a device  60  to be tested, and a tail end  32  which is secured within the main test structure  45  by an elastomeric material  25 . The probes further include a body  34  with the front end  31  emanating from a front extension  35  and the tail end  32  emanating from a tail extension  36 . The body  34  includes an arcuate surface  40  which engages a trace within the main test structure  45 . The front extension  35  further includes a linear portion  39  which engages a first seat  49  within the main test structure  45  when engaged by the device to be tested  60  and the tail end  32  engages a second seat  51  located proximally to the elastomeric material  25 . 
     Looking more specifically to the figures, there is illustrated the various components of the instant invention.  FIGS.  1  and  2    illustrate a test socket  10  which includes a guide plate  15  with an upper surface  16  and a lower surface  20  which is substantially parallel to the upper surface  16  and facing the opposite direction. The guide plate  15  includes a recessed opening  17  located on its upper surface  16 . The recessed opening  17  does not extend through the body  21  of the guide plate  15 . The guide plate  15  also includes an opening  19  located within the recessed opening which extends through body  21  of the guide plate  15  to the lower surface  20 . The guide plate  15  also includes one or more pins  18  which engage with the main test structure  45  when the test socket  10  is assembled. The guide plate  15  is made from any material known in the art. The guide plate  15  can be made from a material selected from the group comprising a polyether block amide (PEBA), a polyether ether ketone (PEEK), polyvinyl alcohol (PVA), Polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), polyvinyl, polyamide, polyimide, polyethylene, or a combination thereof. 
     The test socket  10  also comprises a main test structure  45  which includes a body  47  and a plurality of arms  46  which emanate from the body of the main test structure. The body  47  and the arms  46  include an upper surface  50  and a lower surface  53 . Each arm  46  includes one or more apertures which may or may not extend through the arm from the upper surface  50  to the lower surface  53 . Each arm may include a pin aperture  48  which is engaged by a pin  18  from the guide plate  15  when the text socket  10  is assembled. As shown in the figures, the main test structure  45  is constructed of a plurality of layers  52 . The layers  52  define the open chambers within the main test structure  45 . Looking to the figures, a pair of apertures  27  and  28  are illustrated. The first aperture  27  is where the front end  31  each probe  30  extends out of a chamber within the main test structure  45 . The second aperture  28  is the opening of a channel  26  allows for the insertion and removal of an elastomeric material  25  within the channel  26  which secures the probe(s)  30  in place within the main test structure  45 . Each channel  26  runs perpendicular to the orientation of the probes  30  when they are secured within the chamber of the main test structure  45 . The main test structure  45  also includes a ground pad  58  which is known in the art. Within the main test structure  45  there is a first seat  49  which limits the degree of downward movement of the probe  30  when the probe is engaged with a device to be tested. There is also a second seat  51  within the main test structure  45 . The second seat  51  is engaged by the tail end  32  of the probe  30  and aids in maintaining the position of the probe. A shoulder  54  is also defined within the main test structure  45 . Engagement of the shoulder  54  by a protrusion  37  emanating from the body  34  of the probe  30  serves to limit the degree of upward movement of the probe  30  and the distance that the front end  31  of the probe extends beyond the upper surface  50  of the main test structure  45  when the probe  30  is not engaged by a device to be tested. Polyimide films have been the organic dielectric of choice for decades in the microelectronic industry because of the materials&#39; high thermal, chemical, and mechanical stability to temperatures above 300° C. These properties make polyimide films ideal for the material for the main test structure  45 . 
     The test socket also includes one or more probes  30  secured within the main test structure  45 . The probes can be made from any material known in the art including, but not limited to, metals, precious metals and alloys thereof. Each probe  30  can be a high frequency probe. In a preferred embodiment, each probe is manufactured by stamping to ensure and maintain consistency among the probes. The probes may be manufactured by machining, stamping, or a combination thereof. The probe  30  includes a body  34 , a front end  31  emanating from a front extension  35  which is emanating out from the body  34 , and a tail end  32  emanating from a tail extension  36  which is also emanating out from the body  34 . The tail extension  36  narrows, defining the tail end  32  as rounded as clearly illustrated in  FIGS.  1 ,  3 , and  4   . The body includes an arcuate surface  40  which will engage the trace formed on the surface of the tester load board. The arcuate surface  40  will roll and maintain contact with the trace as each device is tested. The body also includes a protrusion  37  which engages a shoulder  54  located within main test structure  45  as described previously above. Each probe  30  also includes a linear protrusion  33  which is located on the front extension  35 . The linear protrusion  33  engages a first seat  49  which limits the degree of downward movement of the probe  30  when the probe is engaged with a device to be tested. 
     As stated previously, an elastomeric material  25  is used to secure the probe(s)  30  in place within the main test structure  45 . The elastomeric material  25  is generally rod shaped and comprised of a material selected from the group including a thermoplastic elastomer, a thermoplastic urethane, a natural rubber, a synthetic rubber, a silica gel, a polymer, a copolymer, a polyolefin, or a combination thereof. The elastomeric material is inserted into a channel  26  located within the main test structure  45  and accessible through the second aperture  28 . 
     It will be understood that various types of integrated circuit devices  55  are able to be tested utilizing a test socket  10  or test set in accordance with the present invention. The test socket  10  is intended for use with a tester generally employed for determining the quality of integrated circuit devices used in electronics. 
     The instant invention also includes a test set mounted to a load board  70  or a tester apparatus to electrically connect one or more leads  64  or terminal pads of a device to be tested  60  with a corresponding metallic trace  72  on the load board  70  comprising a test socket  10  including a guide plate  15  with a lower surface  20  engaged with an upper surface  50  of a main test structure  45 , the guide plate  15  further including an upper surface  16 , which is parallel to the lower surface, and an opening  19  extending through the guide plate, The main test structure  45  includes a body  47  with one or more apertures  27 ,  28  through the upper surface  50  and a plurality of probes  30  mounted within the main test structure  45 , the probes including a front end  31  emanating from a front extension  35  which extends through the apertures  27  for engagement by a lead  64  or terminal pad of a device to be tested  60 , and a tail end  32  emanating from a tail extension  36  which is secured within the main test structure  45  by an elastomeric material  25 , and the body  34  includes an arcuate  40  surface which engages a trace on the load board or tester apparatus, wherein the front extension  35  further includes a linear portion  39  which engages a first seat  49  within the main test structure  45  when engaged by the device to be tested  60  and wherein the tail end  32  includes a narrowed section and an expanded end which engages a second seat  51  located proximally to the elastomeric material  25  to maintain the probes  30  in a desired position/orientation. 
     The test set described above may incorporate any design element contained within this application and any other document/application incorporated by reference herein. The test set described above may include a main test structure  45  made from polyimide film, and may include a guide plate made from a material selected from the group comprising: a polyether block amide (PEBA), a polyether ether ketone (PEEK), polyvinyl alcohol (PVA), Polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), polyvinyl, polyamide, polyimide, polyethylene, or a combination thereof. The test set described above may include an elastomeric material  25  which is rod shaped and comprised of a material selected from the group including a thermoplastic elastomer, a thermoplastic urethane, a natural rubber, a synthetic rubber, a silica gel, a polymer, a copolymer, a polyolefin, or a combination thereof. The test set described above may include precompression of the elastomeric material  25  by the one or more probes  30  and further compression by the probe(s)  30  as the front end  31  of the probe is engaged by the lead or terminal pad of the device to be tested and urged into the aperture. The test set described above may include a shoulder defined by said housing for engaging the probe and limiting the distance the probe extends beyond the upper surface of the main test structure. 
     The instant invention also includes a method of testing a device using any of the test sockets or test sets described herein. Any method described herein may incorporate any design element contained within this application and any other document/application incorporated by reference herein. 
     In describing the invention, it will be understood that a number of techniques and steps are disclosed. Each of these has individual benefit and each can also be used in conjunction with one or more, or in some cases all, of the other disclosed techniques. Accordingly, for the sake of clarity, this description will refrain from repeating every possible combination of the individual steps in an unnecessary fashion. Nevertheless, the specification and claims should be read with the understanding that such combinations are entirely within the scope of the invention and the claims. 
     The present invention may be embodied in other forms without departing from the spirit and the essential attributes thereof, and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention. The invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein.