This invention is on the design and development of new second level interconnects for testing packages.
As IC (integrated circuit) dies become smaller, include more transistors, and are packaged in smaller packages, the connection arrays on these packages become smaller. More connections are closer together. For example BGA (Ball Grid Array) packages become smaller and thinner in size with finer pitch arrays. To test these devices, a temporary connection is made to each connector. This temporary connection is used to operate the die at the limit of speed and voltage for purposes of testing. The test is a critical step before the packaged die is attached to a motherboard or socket and used in a device. At the same time the test and the tester may require a significant cost in materials and time.
The tester must be inexpensive and still provide a very reliable, quick, and low force connection to the connection array of the die package. One common tester uses pogo-pins to contact the balls of a BGA device. The pogo pins are spring-based and provide high compliance, durability and reliability. As the number of contacts increases, the number of pogo pins also increases and the pogo pins must be closer together to match the pitch of the BGA.
Embodiments of the invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements.
In some embodiments a simple interconnect is used as a contactor to connect a packaged die to a circuit board. The circuit board conducts input and output signals from a test system to the packaged die through the contactor.
The wires 106 extend through and from the first aligner 108 through an insulation layer 108 and through holes of a second aligner 110 to contact pads or lands, which in this case are in the form of solder balls 114 but may be any other type of connector of the packaged die 112. The second aligner is proximate the packaged die. The package die will be referred to herein as a DUT (Device Under Test) to distinguish it from other components of the system.
The first and second aligners each have a hole for each wire. These holes hold the wires in alignment with the PCB and DUT respectively but allow for the wire to move vertically as it is compressed. The insulating layer has a slot 109 for each wire. The slots allow the wire to move vertically but also allow the wires to move laterally, with respect to their length, across the slot. The slots have a shape that is longer in one direction than the other orthogonal direction. As shown, the wires 106 are formed with a bend that that forms an arc outward laterally from the two ends. When compressed, the arc of the wire moves further laterally. The slot permits this lateral movement. The slot also prevents the wires from rotating because the arc is captured in the slot.
The PCB may be a separate test board of a test fixture. Multiple contactors may be mounted to this PCB so that multiple packaged dies may be tested simultaneously. In another example, the PCB is within a socket. The socket receives the packaged die for test. There may be multiple sockets attached to a larger main test board. The PCB may be used in another way as a test fixture. The PCB in general applies signals through the wires to connections on the DUT. It also receives signals from the DUT which are then analyzed by the test fixture. A variety of different functional and performance tests may be performed to determine whether the packaged die operates correctly and provides the performance desired.
Spacers 126 are installed on all four sides of the central insulating layer 108. The spacers establish a distance between the two aligners when the contactor is assembled. The spacers maintain a distance between the insulating layer and the first and second aligner on either side of the insulating layer. The contactor is held together by screws 130 that are secured into nuts 128 attached to the DUT side aligner. Other fasteners may be used instead to suit particular applications and form factors
The cross section of each of the wire probes may be circular, rectangular, or any other desired shape, depending on the desired characteristics of the particular implementation. For a circular coated wire the interior of the wire provides the spring force against mechanical loads while the coating carries the current. When a rectangular cross-section is used, the middle insulating layer may be removed.
The wire probe has a length shown here in the vertical direction. The pressure is longitudinal against the wire and, due to the bend and the resiliency of the wire material, the wire is resilient against the longitudinal compression shown in
A base fixture 602 of the assembly kit may be made of rigid material such as aluminum and houses a stencil 604 that is covered by a tacky adhesive, thermal grease or any other desired light adhesive may be used. The stencil material may be formed of a dimensionally stable material such as a nickel-iron alloy like Invar. The DUT side aligner 110 as shown in
The insulating layer 108 also has slots 109 for each of the wire probes, however, the alignment is not as precise. The insulating layer is used to prevent the probes from rotating while allowing the probes to be compressed as shown in
All the components of the assembly kit of
At 504 the wire probes are inserted into the assembly kit. The probes may be individually placed in each slot of the insulating layer 108 and then through the corresponding DUT side aligner hole. The probes are pushed into the stencil and are held in place by the adhesive layer.
At 506 after all the probes are placed into the assembly kit, the tips of all of the probes are captured using a cover 624. In some embodiments a glass top sheet is temporarily placed over the insulating layer to capture the probe tips as shown in
At 508 the insulating layer assembly is translated up or down or both along the wire probes. This moves the insulating layer between the base fixture and the insulating layer. This movement rotates any wire probes by moving the respective slot across each probe. The probes are then in alignment and the insulating layer may stop in a location that prevents any further rotation of the probes. This location may be the location as shown in
At 510 spacers 126 are installed on all four side of the insulating layer. This is shown in the diagram of
At 512, the PCB side aligner 104 is placed over the insulating layer after the glass cover is removed as shown in
At 514, after the PCB side aligner is in position, screws 130 or another fastener may be used to hold all of the components together as shown in
At 516, the base fixture 602 is removed leaving only the two aligners and the insulating layer. The completed contactor is shown in
The DUT frame 116 is mounted over the contactor 72 using alignment pins 122 and carries the DUT 50. The DUT frame compresses the test probes 78 of the contact array on to a connection pad of a testing PCB (Printed Circuit Board) 70. Additional mounting rings, holders, space transformers, brackets, and other structures may be used to hold the assembly in place and secure the DUT to the test contacts. The PCB then connects to ATE (Automated Test Equipment) 68 through a cable, routing layers, or any other desired connection type 56. The ATE drives the test and measures the results through the test probes. Various passives 54 condition power and data signal lines to resemble an operational installation or to improve test results.
The example of
Depending on its applications, computing device 100 may include other components that may or may not be physically and electrically coupled to the board 2. These other components include, but are not limited to, volatile memory (e.g., DRAM) 8, non-volatile memory (e.g., ROM) 9, flash memory (not shown), a graphics processor 12, a digital signal processor (not shown), a crypto processor (not shown), a chipset 14, an antenna 16, a display 18 such as a touchscreen display, a touchscreen controller 20, a battery 22, an audio codec (not shown), a video codec (not shown), a power amplifier 24, a global positioning system (GPS) device 26, a compass 28, an accelerometer (not shown), a gyroscope (not shown), a speaker 30, a camera 32, and a mass storage device (such as hard disk drive) 10, compact disk (CD) (not shown), digital versatile disk (DVD) (not shown), and so forth). These components may be connected to the system board 2, mounted to the system board, or combined with any of the other components.
The communication chip 6 enables wireless and/or wired communications for the transfer of data to and from the computing device 100. The term “wireless” and its derivatives may be used to describe circuits, devices, systems, methods, techniques, communications channels, etc., that may communicate data through the use of modulated electromagnetic radiation through a non-solid medium. The term does not imply that the associated devices do not contain any wires, although in some embodiments they might not. The communication chip 6 may implement any of a number of wireless or wired standards or protocols, including but not limited to Wi-Fi (IEEE 802.11 family), WiMAX (IEEE 802.16 family), IEEE 802.20, long term evolution (LTE), Ev-DO, HSPA+, HSDPA+, HSUPA+, EDGE, GSM, GPRS, CDMA, TDMA, DECT, Bluetooth, Ethernet derivatives thereof, as well as any other wireless and wired protocols that are designated as 3G, 4G, 5G, and beyond. The computing device 500 may include a plurality of communication chips 506. For instance, a first communication chip 506 may be dedicated to shorter range wireless communications such as Wi-Fi and Bluetooth and a second communication chip 506 may be dedicated to longer range wireless communications such as GPS, EDGE, GPRS, CDMA, WiMAX, LTE, Ev-DO, and others.
The processor 4 of the computing device 100 includes an integrated circuit die packaged within the processor 4 In some implementations of the invention, the integrated circuit die of the processor, memory devices, communication devices, or other components include one or more packaged dies and the packages are tested using a contactor as described above. The term “processor” may refer to any device or portion of a device that processes electronic data from registers and/or memory to transform that electronic data into other electronic data that may be stored in registers and/or memory.
In various implementations, the computing device 100 may be a laptop, a netbook, a notebook, an ultrabook, a smartphone, a tablet, a personal digital assistant (PDA), an ultra mobile PC, a mobile phone, a desktop computer, a server, a printer, a scanner, a monitor, a set-top box, an entertainment control unit, a digital camera, a portable music player, a digital video recorder, a wearable device, or a node for an Internet of Things (IoT). In further implementations, the computing device 100 may be any other electronic device that processes data.
Embodiments may be adapted to be used with a variety of different probe wires, probe heads, and devices under test using various types of testing equipment for different implementations. References to “one embodiment”, “an embodiment”, “example embodiment”, “various embodiments”, etc., indicate that the embodiment(s) of the invention so described may include particular features, structures, or characteristics, but not every embodiment necessarily includes the particular features, structures, or characteristics. Further, some embodiments may have some, all, or none of the features described for other embodiments.
In the following description and claims, the term “coupled” along with its derivatives, may be used. “Coupled” is used to indicate that two or more elements co-operate or interact with each other, but they may or may not have intervening physical or electrical components between them.
As used in the claims, unless otherwise specified, the use of the ordinal adjectives “first”, “second”, “third”, etc., to describe a common element, merely indicate that different instances of like elements are being referred to, and are not intended to imply that the elements so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.
The drawings and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, the specific location of elements as shown and described herein may be changed and are not limited to what is shown. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims.
The following examples pertain to further embodiments. The various features of the different embodiments may be variously combined with some features included and others excluded to suit a variety of different applications. Some embodiments pertain to a contactor that includes a plurality of wire probes formed to be resilient against longitudinal pressure, a first aligner proximate one end of the wire probes having a first plurality of holes through which the wire probes extend, the first alignment layer to align the wire probes to contact pads of a text fixture, a second aligner proximate the other end of the wire probes having a second plurality of holes through the wire probes extend, the second alignment layer to align the wire probes to contact pads of a device under test, and an insulating layer between the first and the second aligner through which the wire probes extend to hold the wire probes when compressed by longitudinal pressure.
Further embodiments include a plurality of spacers attached to the insulating layer to establish a distance between the first and second aligners and maintain a distance between the insulating layer and the first and second aligners.
In further embodiments the first and second aligner are dielectric.
In further embodiments the dielectric is ceramic.
In further embodiments the first and second aligners are attached together.
In further embodiments the insulating layer has a plurality of slots through which the wire probes extend to prevent the wire probes from rotating.
In further embodiments the second plurality of holes have a rectangular cross-section to further prevent the wire probes from rotating.
In further embodiments the wire probes are formed with a bend that forms an arc and wherein the insulating layer has a plurality of slots through which the arcs of the wires extend allowing the wire probes to move longitudinally through the slots.
In further embodiments the wire probes have either a circular or rectangular cross-section and wherein the rectangular cross-section wire probes do not have a middle insulating layer.
Further embodiments include a frame having alignment features to align the second aligner to the frame and pins to align the frame to a circuit board, the frame attaching the first and second aligner to the circuit board.
In further embodiments the frame includes a socket to hold the device under test in contact with the wire probes.
Some embodiments pertain to a packaged integrated circuit die test system that includes a circuit board having a contact array and a connector to automated test equipment, and contactor mounted to the circuit board and electrically connected to the circuit board, the contactor having a plurality of wire probes formed to be resilient against longitudinal pressure, a first aligner proximate one end of the wire probes having a first plurality of holes through which the wire probes extend, the first alignment layer to align the wire probes to contact pads of a text fixture, a second aligner proximate the other end of the wire probes having a second plurality of holes through the wire probes extend, the second alignment layer to align the wire probes to contact pads of a device under test, and an insulating layer between the first and the second aligner through which the wire probes extend to hold the wire probes when compressed by longitudinal pressure.
In further embodiments the contactor further comprises a frame having alignment features to align the second aligner to the frame and pins to align the frame to the circuit board, the frame attaching the first and second aligner to the circuit board.
Some embodiments pertain to a method that includes inserting a first end of a plurality of probe wires each through a respective hole of an insulating layer and of a first alignment layer into an adhesive, the wire probes to connect contact pads of a device under test to contact pads of a test fixture, placing a top over a second end of the inserted probe wires to prevent the probe wires from moving away from the adhesive, translating the insulation layer away from the first alignment layer and the first ends of the probe wires, removing the top and placing the second ends of the inserted probe wires through holes of a second aligner so that the second ends are held by the second aligner, and fastening the second aligner to the first aligner.
Further embodiments include applying spacers to the insulating layer before fastening, the spacers to maintain a distance between the insulating layer and the first and second aligners when the first and second aligners are fastened together.
In further embodiments the wire probes are formed with an arc-shaped bend, wherein the holes of the insulation layer are elongated as slots, and wherein translating the insulation layer comprises moving the insulation layer until the bends are aligned with the slots.
In further embodiments translating comprises rotating the wire probes using the slots so that the arc-shaped bends of the wire probes are aligned.
In further embodiments the adhesive is on a base fixture under the first aligner, the method further comprising removing the base fixture after removing the top.
Further embodiments include attaching the fastened second and first aligner to a circuit board by attaching a frame over the second and the first aligner and to the circuit board.
Further embodiments include attaching a device under test to the frame.