Pusher pin having a non-electrically conductive portion

An electrically insulative pusher pin is disclosed. In one example, an electrically insulative pusher pin includes a first plunger member, a second plunger member, and a spring. The first plunger member has a first end and an exposed second end. The second plunger member has a first end and an exposed second end. The second plunger member is movable relative to the first plunger member, where the exposed second ends of the first and second plunger members defining a length of the pusher pin. The spring disposed between the first ends of the first and second plunger members and biases the exposed second end of the first plunger member away from the exposed second end of the second plunger member. An electrically insulative path is defined between the exposed second end of the first plunger member and the exposed second end of the second plunger member through the pusher pin.

BACKGROUND

Field

Examples of the present disclosure generally relate to a pusher pin. In particular, examples of the present disclosure relate to a pusher pin having an electrically non-conductive portion for use in an automated test assembly.

Description of the Related Art

Electronic devices, such as tablets, computers, server, in-door telecom, out-door telecom, industrial computers, high performance computing data centers, copiers, digital cameras, smart phones, control systems and automated teller machines, among others, often employ electronic components which leverage chip packages for increased functionality and higher component density. Conventional chip packages include one or more stacked components such as integrated circuit (IC) dies, through-silicon-via (TSV) interposer, and a package substrate, with the chip package itself stacked on a printed circuit board (PCB). The IC dies may include memory, logic, MEMS, RF or other IC device.

Prior to incorporation into an electronic device, chip packages are tested to ensure that the performance of the chip packages meet predefined performance criteria. In most conventional automatic test equipment utilized to test chip packages, some type of clamp or actuator is utilized to force the chip package into a test socket that electrically couples the circuitry of the chip package with test circuitry of the automatic test equipment. The actuator of the automatic test equipment is typically coupled to a first end of a workpress. A second end of the workpress has a surface specifically designed to engage the top surface of the chip package while pressing the chip package into the test socket. The actuator is configured to move the workpress to thus apply a force to the top of the chip package, thus urging the chip package into the test socket. Because second surface of the workpress contacting the chip package is typically machined out of aluminum, workpress may not apply force as designed to the chip package due to height differences on the chip package, such as for example differences in height between stiffeners, lids, package substrates and the like. The nonuniform application of force results in some regions of the chip package receiving too much force while other regions not receiving enough force to ensure good electrical connection between the chip package and test socket. Undesirably, this may lead to damage to and poor testing of the chip package. The challenges of applying force as intended increases dramatically in lidless chip packages where differences in die heights may be very varied.

Thus, there is a need for improved equipment and methods for testing chip packages.

SUMMARY

Examples of the present disclosure relate to a pusher pin having an electrically non-conductive portion for use in an automated test assembly. In one example, an electrically insulative pusher pin includes a first plunger member, a second plunger member, and a spring. The first plunger member has a first end and an exposed second end. The second plunger member has a first end and an exposed second end. The second plunger member is movable relative to the first plunger member, where the exposed second ends of the first and second plunger members defining a length of the pusher pin. The spring disposed between the first ends of the first and second plunger members and biases the exposed second end of the first plunger member away from the exposed second end of the second plunger member. An electrically insulative path is defined between the exposed second end of the first plunger member and the exposed second end of the second plunger member through the pusher pin.

In another example, an integrated circuit package test assembly that employs at least one electrically insulative pusher pin is disclosed. The integrated circuit package test assembly includes a workpress, a socket and an actuator. The workpress has a top end and a bottom end. The bottom end of the workpress has a first plurality of pusher pins. The socket has a top end facing the bottom end of the workpress. The top end of the socket has a second plurality of pusher pins. The actuator is configured to move the workpress towards the socket a sufficient distance to cause the first plurality of pins and the second plurality of pins to engage a device under test (DUT) when disposed in the socket. At least a first pusher pin of the first plurality of pusher pins or at least one pusher pin of the second plurality of pusher pins has an open circuit defined between opposite ends of the first pusher pin.

In another example, a method of testing an integrated circuit package in an integrated circuit package test assembly. The method includes contacting a DUT with at least a first non-conductive pusher pin on a top surface or a bottom surface of the DUT, contacting the DUT with at least a first conductive pusher pin on the top surface or the bottom surface of the DUT, and testing the DUT in contact with the first non-conductive pusher pin and the first conductive pusher pin though signals provided through the first conductive pusher pin.

In another example, the method of testing described above may be implemented with a non-conductive pusher pin which is fabricated as an assembled compliant plunger, a stamped or formed plunger, a slider plunger, an H-slider pin, a spring pin, a buckling pin, a cobra pin, a pogo-pin, a microelectromechanical (MEMS) pin or other workpiece pusher suitable for contacting surfaces of a lid-less chip package.

In another example, the method of testing described above may be implemented with a non-conductive pusher pin which has a unitary construction that incorporates a spring form. That is, the non-conductive pusher pin is made from a single mass of material to provide the unitary construction. For example, the unitary construction may be achieved through stamping, machining, MEMS fabrication techniques, 3D printing or other suitable technique.

In another example, the method of testing described above may be implemented with a non-conductive pusher pin which incorporates a compressible, resilient material that allows the pusher pin to change length. The compressible, resilient material may be a foam, an elastomer, plastic spheres or other suitable material.

DETAILED DESCRIPTION

Examples of the disclosure generally provide electrically insulative pusher pins for use in integrated circuit package test assemblies. In first examples described herein, techniques are provided that allow for a distributed force to be applied over a larger contact area, resulting in reduced pressure applied to DUTs, such as integrated circuit chips, integrated circuit chip packages, printed circuit boards, and the like, thereby reducing the risk of die and/or package delamination and die and/or substrate cracks. In second examples described herein, techniques are provided that include an electrically insulative path defined between opposite ends of a pusher pin. The electrically insulative path defined through the pusher pin prevents the pusher pin from inadvertently shorting circuits that may be in contact with the pusher pin when in use with DUTs.

FIG. 1show a perspective of an exemplary pusher pin100. The pusher pin100, which may be adapted from a pogo pin, spring pin, buckling pin, cobra pin, microelectromechanical (MEMS) pin and the like, includes a first plunger member108, a second plunger member116and a spring115. In one example, an electrically insulative path is defined between the exposed opposite ends of the first and second plunger members108,116through the pusher pin100. The electrically insulative path defined through the pusher pin100prevents the pusher pin100from inadvertently shorting circuits that may be in contact with the pusher pin100when in use. It is noted that the pusher pin100described herein although for use in DUTs, is not intended for use in locations that require communication of an electric signal, ground or power for which a conventional pusher pin is commonly utilized.

The first plunger member108has a body150. The body150includes a first end113and a second end110. The body150may be cylindrical or have another sectional geometry. The body150may be fabricated from a material suitably rigid enough to withstand an axial compression force exerted on the pusher pin100when in use with a DUT. For example, the body150is configured to withstand axial compression force of up to about 1000 grams In one example, the body150maybe fabricated from a carbon-based materials, fiber-reinforced plastic, metals, rigid polymers or other suitable material. Suitable metals include brass, stainless steel, beryllium copper and titanium, among others. The body150maybe fabricated form one or more materials, and in one example, at least a portion of the body150is fabricated from a dielectric material so that the body150is not conductive from the end113to the end110.

The second plunger member116also has a body152. The body152may be fabricated from the same materials as described above with reference to the body150of the first plunger member108. The bodies150,152may be fabricated from the same materials, or fabricated from different materials. In some examples, at least one of the bodies150,152is non-conductive end to end, while in other example, both bodies150,150may be conductive end to end. The body152of the second plunger member116includes a first end119and a second end120.

The pusher pin100may further include a shell102. The shell102optionally may be part of the first plunger member108. The shell102may be fabricated from the same materials as described above with reference to the body150of the first plunger member108. The body150and the shell102may be fabricated from the same materials, or fabricated from different materials. In some examples, at least one of the body150and the shell102is non-conductive end to end, while in other example, both the body150and shell102may be conductive end to end.

The shell102has a first end104and a second end106. A cavity107is formed through the shell102from the first end104to the second end106. The first end113of the first plunger member108is disposed in the cavity107through the first end104of the shell102. In one example, the first end113of the first plunger member108is fixed in the cavity107of the shell102so that the first plunger member108does not move relative to the shell102. The first plunger member108may be fixed to the shell102in any suitable manner. For example, the first plunger member108may be fixed to the shell102using adhesives, a press fit engagement, a swaged connection, threads, crimping, brazing, welding, fasteners or other suitable technique. In another example, the first end113of the first plunger member108is movably disposed in the cavity107of the shell102so that the first plunger member108may move axially relative to the shell102. In such embodiment where it is desirable for the first plunger member108to move axially relative to the shell102, the first end113of the first plunger member108may be captured in the cavity107of the shell102as further described below with reference to the engagement of the second plunger member116with the cavity107of the shell102.

As just mentioned above, the second plunger member116is engaged with the cavity107of the shell102in a manner that allows for the second plunger member116to move axially relative to the shell102. For example, the first end119of the second plunger member116is disposed in the cavity107through the second end106of the shell102. The shell102includes a flange156that has an inner diameter sized to allow the body152of the second plunger member116to extend through the flange156so that the second plunger member116may be displaced axially through the second end106of the shell102without significant restriction of movement. The flange156may be formed by crimping the shell102, heading, or other suitable technique. The inner diameter of the flange156is smaller than a diameter of a head154formed at the second end106of the second plunger member116, thus capturing the second plunger member116within the cavity107by preventing the second plunger member116from completely sliding out of the cavity107through the second end106of the shell102. In one example, the second plunger member116may be displaced axially through a distance of about 0.5 to about 2.5 millimeters.

The spring115is fabricated from a conductive or non-conductive material and is disposed between the first plunger member108and the second plunger member116. The spring115biases the first plunger member108away from the second plunger member116. The spring115may be disposed within or outside of the shell102. In the example depicted inFIG. 1, the spring115is disposed in the cavity107of the shell102.

For example, the spring115has a first end112and a second end118. The first end112of the spring115is disposed against the first end113of the body150of the first plunger member108. The end118of the spring115is disposed against the first end119of the body152of the second plunger member116. The distance between the first end113of the body150of the first plunger member108and the flange156of the shell102is selected so that the spring115generates a determined pre-load force when the second plunger member116is fully extended from the shell102. In one example, the spring115is selected to generate a force of between about 0.15 to 1.00 newtons (N) at about half the stroke of the second plunger member116.

As discussed above, an electrically insulative path is defined through the pusher pin100. That is, an open circuit is formed between the second ends110,120of the plunger members108,116that defined the length of the pusher pin100. The electrically insulative path defined through the pusher pin100generally prevents the pusher pin100from inadvertently shorting circuits that may be in contact with the second ends110,120of the pusher pin100when in use. To achieve an electrically insulative path through the pusher pin100, various elements of the pusher pin100may be made of or coated with an electrically insulative material so that an open circuit is formed between exposed second ends110,120of the pusher pin100. The electrically insulative material may be a ceramic, a form of rubber or latex, plastic, glass, or other suitable electrically insulative material. The electrically insulative material may also be an electrically non-conductive coating applied over a dielectric or conductive base material. The electrically non-conductive coating may comprise a thin film of ceramic, a form of rubber or latex, plastic, glass, or other suitable electrically insulative material.

In the example depicted inFIG. 1, the second end110of the first plunger member108may include electrically insulative tip114. The electrically insulative tip114may be made from or coated with any of the electrically insulative materials described above, including an electrically non-conductive coating applied over a dielectric or conductive base material, the coating comprised a thin film of ceramic, a form of rubber or latex, plastic, glass, or other suitable electrically insulative material. The electrically insulative tip114may be part of the body150, or be separately connected to the second end110of the first plunger member108. The electrically insulative tip114provides an open circuit between the second ends110,120of the pusher pin100, thus making the pusher pin100non-conductive.

Optionally and as additionally shown inFIG. 1, the electrically insulative tip114may have a width that is wider than an outer diameter of the shell102. The wide tip114advantageously distributes the force generated by the pusher pin100across a larger area when contacting a die or other DUT as compared to conventional pusher pins, thus reducing the pressure applied to the DUT and decreasing the probability of the DUT becoming damaged through interaction with the pusher pin100. Additionally, since the tip114is electrically insulative, the tip114cannot short adjacent circuits that are in contact with the tip114, thus allowing the use of widths for the second end120of the pusher pin100that are much wider than conventional pusher pins, thereby allowing contact forces to be advantageously spread much wider than conventional pusher pin designs.

In addition to the electrically insulative tip114of the first plunger member108, the second end120of the second plunger member116may include an electrically insulative tip124. The electrically insulative tip124may be made from or coated with any of the electrically insulative materials described above, including an electrically non-conductive coating applied over a dielectric or conductive base material, the coating comprised a thin film of ceramic, a form of rubber or latex, plastic, glass, or other suitable electrically insulative material. The electrically insulative tip124may be part of the body152, or be separately connected to the second end120of the second plunger member116. The electrically insulative tip124provides an open circuit between the second ends110,120of the pusher pin100, thus making the pusher pin100non-conductive. Having the electrically insulative tips114,124on both ends110,120of the pusher pin100advantageously allows the pin100to engage circuits from either end of the pin100without fear of shorting the circuits though electrical connection with another portion of the pin100and another conductive object.

FIG. 2shows a perspective of an exemplary pusher pin200having an electrically insulative tip214, according to an embodiment. The pusher pin200may be fabricated the same as the pusher pin100described above, except wherein the electrically insulative tip214is disposed on the first plunger member108without a second electrically insulative tip disposed on the end120of the second plunger member116. The electrically insulative tip214may be fabricated from a ceramic, a form of rubber or latex, plastic, glass, or other suitable electrically insulative material. The electrically insulative tip214may alternatively be fabricated with an electrically non-conductive coating applied over a dielectric or conductive base material, the coating comprised a thin film of ceramic, a form of rubber or latex, plastic, glass, or other suitable electrically insulative material. The electrically insulative tip214may be part of the body150, or be separately connected to the second end110of the first plunger member108. In embodiments where the electrically insulative tip214is separately connected to the second end110of the first plunger member108, the tip214may be connected to the body150utilizing fasteners, adhesives, swaging, press-fit, threading, pins, or other suitable fastening technique. The electrically insulative tip114provides an open circuit between the second ends110,120of the pusher pin100, thus making the pusher pin100non-conductive.

The enlarged width of the electrically insulative tip114advantageously distributes the force generated by the pusher pin100across a larger area when contacting a die or other DUT as compared to conventional pusher pins, thus decreasing the probability of the DUT becoming damaged through interaction with the pusher pin100.

FIG. 3shows a perspective of an exemplary pusher pin300having an electrically insulative tip324, according to an embodiment. The second end120of the second plunger member116may include the electrically insulative tip324. The electrically insulative tip324may be made from or coated with any of the electrically insulative materials described above. The electrically insulative tip314may alternatively be fabricated with an electrically non-conductive coating applied over a dielectric or conductive base material, the coating comprised a thin film of ceramic, a form of rubber or latex, plastic, glass, or other suitable electrically insulative material The electrically insulative tip324may be part of the body152, or be separately connected to the second end120of the second plunger member116. In embodiments where the electrically insulative tip324is separately connected to the second end120of the second plunger member116, the tip324may be connected to the body152utilizing fasteners, adhesives, swaging, press-fit, threading, pins, or other suitable fastening technique.

When the electrically insulative tip324is part of the body152, both the tip324and the body152may be made of or coated with an electrically insulative material, such as any of the electrically insulative materials described with reference to the body152of the second plunger member116. The tip324and the body152may be fabricated from the same materials, or fabricated from different materials. Since the tip324is electrically insulative, the tip324cannot short adjacent circuits that are in contact with the tip324. The electrically insulative tip324provides an open circuit between the second ends110,120of the pusher pin300, thus making the pusher pin300non-conductive.

A tip314of the first plunger member108is also shown inFIG. 3. The tip314may be fabricated from a conductive or non-conductive material. The tip314may have a width that is wider than an outer diameter of the shell102. The wide tip314advantageously distributes the force generated by the pusher pin300across a larger area when contacting a die or other DUT as compared to conventional pusher pins, thus decreasing the probability of the DUT becoming damaged through interaction with the pusher pin300. In embodiments that the tip314is fabricated from or coated with an electrically insulative material, the tip314cannot short adjacent circuits that are in contact with the tip314, thus allowing the use of widths for the second end110of the pusher pin300that are much wider than conventional pusher pins, thereby allowing contact forces to be advantageously spread much wider than conventional pusher pin designs.

FIG. 4shows a perspective of an exemplary pusher pin400having an electrically insulative first plunger member408, according to an embodiment. The first plunger member408has a body450. The body450includes a second end110. The body450may be cylindrical or have another sectional geometry. The body450may be fabricated from a material suitably rigid enough to withstand an axial compression force exerted on the pusher pin400when in use with a DUT. For example, the body450is configured to withstand axial compression force of up to about 1000 grams. In one example, the body450maybe fabricated from a carbon-based materials, fiber-reinforced plastic, rigid polymers or other suitable electrically insulative material. The body450maybe fabricated form one or more materials, and in one example, at least a portion of the body450is fabricated from a dielectric material so that the body450is not conductive from the end113to the end110.

The electrically insulative first plunger member408may include the tip314that is part of the body450, or is separate from the body450. In embodiments where the tip314is separately connected to the second end110of the first plunger member406, the tip314may be connected to the body450utilizing fasteners, adhesives, swaging, press-fit, threading, pins, or other suitable fastening technique.

When the tip314is part of the body450, both the tip314and the body450may be made of or coated with an electrically insulative material, such as any of the electrically insulative materials described with reference to the body150of the first plunger member108. The tip314and the body150of the first plunger member408may be fabricated from the same materials, or fabricated from different materials. Since the first plunger member408is electrically insulative, the first plunger member408cannot short adjacent circuits that are in contact with the first plunger member408. The electrically insulative first plunger member408provides an open circuit between the second ends110,120of the pusher pin400, thus making the pusher pin400non-conductive.

FIG. 5shows a perspective of an exemplary pusher pin500having an electrically insulative second plunger member516, according to an embodiment. The second plunger member516has a body552fabricated from or coated with an electrically insulative material. The body552includes a first end119and a second end120. The body552may be cylindrical or have another sectional geometry. The body552may be fabricated from a material suitably rigid enough to withstand an axial compression force exerted on the pusher pin500when in use with a DUT. For example, the body552is configured to withstand axial compression force of up to about 1000 grams. In one example, the body552maybe fabricated from a carbon-based materials, fiber-reinforced plastic, rigid polymers or other suitable electrically insulative material. The body552maybe fabricated form one or more materials, and in one example, at least a portion of the body552is fabricated from a dielectric material so that the body552is not conductive from the end119to the end120.

The electrically insulative second plunger member516may include the tip124that is part of the body552, or is separate from the body552. In embodiments where the tip124is separately connected to the first end119of the second plunger member516, the tip124may be connected to the body552utilizing fasteners, adhesives, swaging, press-fit, threading, pins, or other suitable fastening technique.

When the tip124is part of the body552, both the tip124and the body552may be made of or coated with an electrically insulative material, such as any of the electrically insulative materials described with reference to the body152of the second plunger member116. The tip124and the body552of the second plunger member516may be fabricated from the same materials, or fabricated from different materials. Since the second plunger member516is electrically insulative, the second plunger member516cannot short adjacent circuits that are in contact with the second plunger member516. The electrically insulative first plunger member408provides an open circuit between the second ends110,120of the pusher pin500, thus making the pusher pin500non-conductive.

FIG. 6shows a perspective of an exemplary pusher pin600having an electrically insulative shell602, according to an embodiment. The shell602optionally may be part of the first plunger member108. The shell602has a first end104and a second end106. The shell602may be fabricated from the same electrically-insulative materials as described above with reference to the body150of the first plunger member108. The body150and the shell602may be fabricated from the same materials, or fabricated from different materials. In some examples, at least one of the shell602and the body150is electrically non-conductive from the first end104to the second end106, while in other example, both the shell602and the body150may be conductive end to end.

The shell602includes a flange156that has an inner diameter sized to allow the body152of the second plunger member116to extend therethrough so that the second plunger member116be displaced axially through the second end106of the shell602without significant restriction of movement. The flange156may be formed by crimping the shell602, heading, or other suitable technique. The inner diameter of the flange156is smaller than a diameter of a head154formed at the second end106of the second plunger member116, thus capturing the second plunger member116within the cavity107by preventing the second plunger member116from completely sliding out of the cavity107through the second end106of the shell602.

FIG. 7shows a front elevation of a portion of a first plunger member708of an exemplary pusher pin illustrating an electrically insulative portion704of the first plunger member708, according to an embodiment. The first plunger member708includes a body750made up of the electrically insulative portion704and at least one other portion. The at least one other portion of the body750of the first plunger member708may be fabricated from a conductive material, such as a metal, or from a non-conductive material. All the portions of the body750do not have to be fabricated from the same materials, as long as one portion, e.g., the portion704, is fabricated from a non-electrically conductive material.

In the example depicted inFIG. 7, the first plunger member708includes a first portion702and a second portion706that sandwich the electrically insulative portion704. However, the electrically insulative portion704may be alternatively positioned adjacent one of the portions702,706and not the other portion. The electrically insulative portion704makes the body750non-conductive. That is, the body750is electrically non-conductive along length of the body750from the first portion702to the second portion706due to the intervening non-conductive portion704. The electrically insulative portion704may be fabricated from a ceramic, a form of rubber or latex, plastic, glass, or other suitable electrically insulative material. The electrically insulative portion704may be coupled to the utilizing fasteners, adhesives, swaging, press-fit, threading, pins, or other suitable fastening technique.

Although the electrically insulative portion704is shown as being part of the first plunger member708, any one or more of plunger member116and the shell102may have configured to include an electrically insulative portion704as part of the body152of the plunger member116or shell102.

FIG. 8shows a schematic block diagram of an integrated circuit package test assembly800that employs at least one of the pusher pins100-700described with referenceFIGS. 1-7, or other similar pusher pin. The test assembly800may include an actuator802having a bottom end804. The test assembly800may further include a workpress806having a top end810and a bottom end808. The top end810of the workpress806mates with the bottom end804of the actuator802. The bottom end808of the workpress806is embedded with a first plurality of pusher pins812a-812ntherein. At least one of the pusher pins812a-812nmay be configured as any of the pusher pins100-800described above or other similar conductive pusher pin. The test assembly800may further include a socket814having a top end821and a bottom end818. The top end821of the socket814may include a second plurality of pusher pins820a-820ninserted therein. At least one of the pusher pins820a-820nmay be configured as any of the pusher pins100-700described above or other similar conductive pusher pin. At least one of the first plurality of pusher pins812a-812n(e.g.,812a) and/or at least one of the second plurality of pusher pins820a-820nhas a portion made of or coated with an electrically insulative material corresponding to the pusher pins100-700described above in connection withFIGS. 1-7, thus advantageously preventing shorting of the DUT. The pusher pins1000-1500described below in connection withFIGS. 10-15may also be utilized in the test assembly800.

The test assembly800is configured to test the DUT. The DUT is illustrated inFIG. 8as an integrated circuit package813. The integrated circuit package813includes a substrate817on which one or more dies816a-816nare mounted. The integrated circuit package813may be configured to be pushed into the socket814by the workpress806under the influence of a force applied to the workpress806by the actuator802. The integrated circuit package813is clamped between the workpress806and the socket814while under test in the test assembly800. The test assembly800may further include a test bed824within which a test controller826is electrically coupled to one or more of the pusher pins820a-820nembedded within the socket814that are electrically conductive so that the test controller826may communicate with the integrated circuit package813.

In operation, the actuator802is operated to apply a force to displace the workpress806towards the chip package813disposed in the socket814. In response, the workpress806displaces the first plurality of pusher pins812a-812n. The pusher pins812a-812nmay engage one or more of the dies816a-816nlocated on the substrate817and/or other portion(s) of the chip package813, which, in turn, applies the force over a first area of the one or more dies816a-816nand/or other portion(s) of the chip package813in contact with the pins812a-812n. This force pushes the chip package813into the socket814to engage the second plurality of pusher pins820a-820nin the socket814overlying the test bed824. The test controller826may then apply currents, voltages, and/or sensors (not shown) to test the dies816a-816nthrough the pusher pins820a-820nthat are electrically conductive, or other electrical interconnect established between the package813and socket814.

FIG. 8Ashows one example of an enlarged portion of the chip package813in contact with the pusher pins812a-812d. In the example depicted inFIG. 8A, the pusher pin812ais illustrated contacting a top surface840of the substrate817, the pusher pin812bis illustrated contacting a surface mounted circuit component842disposed on the top surface840of the substrate817, the pusher pin812cis illustrated contacting a stiffener844disposed on the top surface840of the substrate817, and the pusher pin812dis illustrated contacting a top surface of the die816. The surface mounted circuit component842may be a passive circuit component, such as resistors, capacitors, diodes, inductors and the like. Although the pusher pins812a-812dare shown in contact with multiple features (i.e., the top surface840of the substrate817, the die816, the stiffener844, and the surface mounted circuit component842) of the chip package813, the pusher pins812may be optionally limited to contact only one type of the features of the chip package813, to contact only two types of the features feature of the chip package813, to contact only three types of feature of the chip package813, or to contact any desired type(s) or combination of types of features of the chip package813. Returning back toFIG. 8, the pusher pins812a-812n,820a-820nmay apply the force over a larger area than beds of conventional pusher pins with small contact area tips as is found in the related art. Because the force is distributed over a larger area, reduced pressure is applied to the dies816a-816nand the substrate817, thereby reducing the risk of die and/or package delamination and die and/or substrate cracks. Additionally, the pusher pins812a-812n,820a-820nthat are electrically insulative may contact the integrated circuit package813without reduced probability of shorting circuit exposed on the package813, thereby reducing the potential for damaging the package813while in the test assembly800. Furthermore, as the pressure applied to the dies816a-816nand the substrate817by the pusher pins812a-812n,820a-820nis generally decoupled from mechanical manufacturing tolerances, the risk of potential damage the package813while in the test assembly800is much smaller as compared to conventional metal workpress solutions utilized in conventional test systems. TIM may still optionally be employed for additional force spreading and/or enhancing heat transfer to or from the DUT.

FIG. 9is a process flow of a method900of testing an integrated circuit package in an integrated circuit package test assembly800, according to an embodiment. At block905, the test assembly800contacts a DUT with at least a first non-conductive pusher pin on a top surface or a bottom surface of the DUT. At block910, the test assembly800contacts the DUT with at least a first conductive pusher pin on the top surface or the bottom surface of the DUT. At block915, the test assembly800tests the DUT in contact with the first non-conductive pusher pin and the first conductive pusher pin though signals provided through the first conductive pusher pin.

FIG. 10shows a side view of an exemplary pusher pin1000having an external spring115, according to an embodiment. The pusher pin1000is constructed similar to the pusher pins described above in reference toFIGS. 1-9, except wherein the spring115is located outside of the plunger members108,116.

The pusher pin1000has an electrically insulative path defined between opposite ends110,120of the pusher pin1000. The electrically insulative path defined between the opposite ends110,120of the pusher pin1000may be realized in any number of ways. For example, the first end110of a first plunger member108may include an electrically insulative tip114. In another example, a second end120of a second plunger member108may include an electrically insulative tip124. Alternatively, at least one of the first and second plunger members108,116may be fabricated from or coated with an electrically insulative material, or include an electrically insulative portion that prevents electrical conduction between the opposite ends110,120of the pusher pin1000, such as described with reference toFIGS. 4-7.

FIG. 11shows a side view of an exemplary pusher pin1100having a slide mechanism1102coupling the plunger members108,116of the pusher pin1100, according to an embodiment. The slide mechanism1102allows one plunger member, e.g., the plunger member108, to slide linearly relative to the other plunger member, e.g., the plunger member116. The slide mechanism1102may be configured as any suitable linear slide, such as one or more guides slideably mounted to a rail, that enables the plunger members108,116to move relative to each other. A spring115is coupled to the plunger members108,116and biases the ends110,120of the pin1100in opposite directions.

The plunger members108,116may be fabricated from a stamped material, such as a metal, or be machined, casted, molded or otherwise formed. Alternatively, the plunger members108,116may be extruded, molded or otherwise formed from a rigid plastic.

The pusher pin1100has an electrically insulative path defined between opposite ends110,120of the pusher pin1100. The electrically insulative path defined between the opposite ends110,120of the pusher pin1000may be realized in any number of ways. For example, the first end110of a first plunger member108may include an electrically insulative tip114. In another example, a second end120of a second plunger member108may include an electrically insulative tip124. Alternatively, at least one of the first and second plunger members108,116may be fabricated from or coated with an electrically insulative material, or include an electrically insulative portion that prevents electrical conduction between the opposite ends110,120of the pusher pin1100, such as described with reference toFIGS. 4-7.

FIGS. 12-13shows side and front views of an exemplary pusher pin1200having an external spring115, according to an embodiment. The pusher pin1200is configured with first and second plunger members108,116having an “H” configuration that guides the relative motion between the plunger members108,116. In the embodiment depicted inFIGS. 12-13, each plunger member108,116has a flat form that is turned at an angle, such as 30-90 degrees, relative to the other plunger member108,116so that the legs of the “H” configuration of each plunger member108,116can engage with each other. The plunger members108,116may be fabricated from stamped materials, such as metals or rigid plastic.

As with the other pins described above, the pusher pin1200has an electrically insulative path defined between opposite ends110,120of the pusher pin1200. The electrically insulative path defined between the opposite ends110,120of the pusher pin1000may be realized in any number of ways. For example, the first end110of a first plunger member108may include an electrically insulative tip114. In another example, a second end120of a second plunger member108may include an electrically insulative tip124. Alternatively, at least one of the first and second plunger members108,116may be fabricated from or coated with an electrically insulative material, or include an electrically insulative portion that prevents electrical conduction between the opposite ends110,120of the pusher pin1200, such as described with reference toFIGS. 4-7.

FIG. 14shows a sectional view of an exemplary pusher pin1400having a spring1402fabricated from a compressible, resilient material, according to an embodiment. The compressible, resilient material comprising the spring1402may be fabricated from foam, an elastomer or plastic spheres. The spring1402may be fabricated from electrically conductive or insulative material.

As with the other pins described above, the pusher pin1400has an electrically insulative path defined between opposite ends110,120of the pusher pin1400. The electrically insulative path defined between the opposite ends110,120of the pusher pin1000may be realized in any number of ways. For example, the first end110of a first plunger member108may include an electrically insulative tip114. In another example, a second end120of a second plunger member108may include an electrically insulative tip124. Alternatively, at least one of the first and second plunger members108,116may be fabricated from or coated with an electrically insulative material, or include an electrically insulative portion that prevents electrical conduction between the opposite ends110,120of the pusher pin1400, such as described with reference toFIGS. 4-7.

FIG. 15shows a side view of an exemplary pusher pin1500having a unitary construction that incorporates a spring form, according to an embodiment. That is, at least one spring1515and the plunger members108,116are made from a single mass of material to provide the unitary construction. For example, the unitary construction may be achieved through stamping, machining, MEMS fabrication techniques, 3D printing or other suitable technique.

In the embodiment depicted inFIG. 15, two springs1515are utilized which are coupled to a frame1502at one end. The opposite ends (e.g., ends110,120) of each spring1515are coupled to a respective one of the plunger members108,116. In one example, the springs1515are flat springs.

The frame1502laterally surrounds the plunger members108,116and springs1515to provide a guide that orients the pusher pin1500within the receiving hole in which the pusher pin1500is formed. The ends110,120extend axially through a gap in the frame1502a sufficient distance to allow a desired range of motion of the plunger members108,116without the ends110,120retracting within the bounds of the frame1502.

As with the other pins described above, the pusher pin1500has an electrically insulative path defined between opposite ends110,120of the pusher pin1500. The electrically insulative path defined between the opposite ends110,120of the pusher pin1000may be realized in any number of ways. For example, the first end110of a first plunger member108may include an electrically insulative tip114. In another example, a second end120of a second plunger member108may include an electrically insulative tip124. Alternatively, at least one of the first and second plunger members108,116, springs1515may be fabricated from or coated with an electrically insulative material, or include an electrically insulative portion that prevents electrical conduction between the opposite ends110,120of the pusher pin1500, such as described with reference toFIGS. 4-7. In yet another example, the portion of the frame1502separating the springs1515may be fabricated from or coated with an electrically insulative so as to provide an open circuit between the ends110,120of the pusher pin1500.

With all the pusher pins described above, the pusher pins are sized to allow a pitch between axially aligned pusher pins of 1.0 mm centerline to centerline pitch. In other examples, the centerline to centerline pitch may be as small as 0.4 mm. The end to end (i.e., between the ends110,120) range of motion (i.e., axial displacement) of the pusher pins may be in the range of 0.7 to 2.0 mm. The pusher pins may generate between 5.0 and 0.15 newtons of force.

While the foregoing is directed to examples of the present disclosure, other and further examples may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.