Abstract: An integrated circuit (10) comprises a functional circuit (12a-c) that contain information that must be secured against unauthorized access. The integrated circuit comprises a test access circuit (14, 16) coupled to the functional circuit (12a-c), and a plurality of fuse elements (18) coupled to the test access circuit (14, 16). The fuse elements (18) are connected in a circuit configuration that makes the functional circuit (12a-c) consistently accessible via the test access circuit (14, 16) only when first fuse elements (18) of the plurality are in a blown state and second fuse elements (18) of the plurality are in a not-blown state. As a result the integrated circuit can be tested after selectively blowing all of the first fuse elements (18). After testing at least part of the second fuse elements (18) is blown.

Abstract: A system and method is disclosed for functional verification of multi-die 3D ICs. The system and method include a reusable verification environment for testing each die in a stack of dies individually without having to simultaneously operate all of the dies in the stack. The system and method includes converting an input/output (“IO”) trace from a die verification test from a first format to a second format to improve performance.

Abstract: A monolithic stacked integrated circuit (IC) is provided with a known-good-layer (KGL) test circuit and a scan segment in one of its upper layers. The test circuit includes a plurality of inputs, outputs, and multiplexers coupled to the scan segment and to a second layer of the IC. The test circuit further includes a plurality of control elements such that scan testing of the stacked IC may be conducted on a layer-by-layer basis.

Abstract: A monolithic stacked integrated circuit (IC) is provided with a known-good-layer (KGL) path delay test circuit and at least a portion of a critical path in one of its layers. The test circuit includes a plurality of inputs, outputs, a flip-flop coupled to the at least a portion of the critical path and a multiplexer coupled to the flip-flop and to a second layer of the IC. The test circuit further includes a control element such that path delay testing of the IC may be conducted on a layer-by-layer basis.

Abstract: A monolithic stacked integrated circuit (IC) is provided with a known-good-layer (KGL) test circuit and a scan segment in one of its layers. The test circuit includes a plurality of inputs, outputs, and multiplexers coupled to the scan segment and to a second layer of the IC. The test circuit further includes a plurality of control elements such that scan testing of the IC may be conducted on a layer-by-layer basis.

Abstract: A system and method is disclosed for functional verification of multi-die 3D ICs. The system and method include a reusable verification environment for testing each die in a stack of dies individually without having to simultaneously operate all of the dies in the stack. The system and method includes converting an input/output (“IO”) trace from a die verification test from a first format to a second format to improve performance.

Abstract: Provided is a method of assigning a first set of probe pads to an interposer for maximizing a defect coverage for the interposer. The interposer includes a second set of nets and the defect coverage is based on a ratio between a tested net length and an overall net length. The method includes processing the second set such that every net interconnecting more than two micro-bumps is divided into a plurality of nets and every two of the more than two micro-bumps are interconnected by one of the plurality of nets. The method further includes calculating an untested length of each net in the second set; selecting a first net from the second set with the maximum untested length; selecting two probe pads from the first set based on a user-defined cost function; and connecting the two probe pads to the first net with two dummy nets.

Abstract: Systems and methods are disclosed for testing a stack of dies and inserting a repair circuit which, when enabled, compensates for a delay defect in the die stack, particularly where the defect is located in the inter-die data transfer path. Intra-die and inter-die slack values are determined to establish which die or dies in the die stack would benefit from the insertion of a repair circuit.

Abstract: A 2.5D or 3D test architecture includes a logic die, and a memory die. In the 2.5D architecture, the logic die and memory die are mounted on an interposer. In the 3D architecture, the memory die is mounted on the logic die. The logic die includes a control logic wrapped with a processor wrapper. The processor wrapper enables testing components of the control logic. The memory die is also mounted on the interposer. The memory die includes dynamic random access memory and channel selection/bypass logic. The control logic is coupled to the dynamic random access memory via the channel selection/bypass logic, the channel selection/bypass logic being controlled by the processor wrapper.

Abstract: A method of testing an integrated circuit die comprises partitioning a first probe card partition layout of the integrated circuit die having one or more sections comprising a first quantity of section types into a second probe card partition layout having a greater quantity of sections comprising a second quantity of section types, the second quantity of section types being less than the first quantity of section types. The method also comprises using one or more probe cards to test the sections in the second probe card partition layout, each of the one or more probe cards having a test contact pattern that corresponds with a test contact pattern of one of each section type included in the second probe card partition layout.

Abstract: A 2.5D or 3D repair architecture includes a logic die, and a memory die. In the 2.5D architecture, the logic die and memory die are mounted on an interposer. In the 3D architecture, the memory die is mounted on the logic die. The logic has a control logic wrapped with a processor wrapper. The processor wrapper enables testing components of the control logic. The control logic further comprises a wide input/output controller, a built-in-repair analyzer (BIRA), and a repair controller. A method utilizing the repair architecture provides for repairing failed columns and rows of a memory device.

Abstract: A method of testing interconnected dies can include forming a cell for the interconnected dies, applying at least a first input to the cell to perform an open or short defects test, and applying at least a second input to the cell to perform one or more of a resistive defects test or a burn-in-test. Test circuitry for testing an interconnection between interconnected dies can include a wrapper cell embedded within a die where the wrapper cell includes a scannable data storage element, a hold data module, a selection logic, a transition generation module, and one or more additional input ports for receiving inputs causing the wrapper cell to perform an open or short defects test in a first mode and causing the wrapper cell to perform one or more of a resistive defects test in a second mode or a burn-in-test in a third mode.

Abstract: A method of probe card partitioning for testing an integrated circuit die includes providing a first probe card partition layout having a first number of distinct sections. Each distinct section uses a distinct probe card for testing. The first probe card partition layout is repartitioned into a second probe card partition layout having a second number of distinct sections. The second number is less than the first number.

Abstract: A system for functional verification of a chip design includes the chip design, a test generator, a test bench, a verification tool, and a coverage tool. The coverage tool is configured to receive chip design, user input, and coverage files from the verification tool to generate information for the test generator to improve the test coverage of the verification tool. The method includes receiving a chip design, functionally testing the chip design, generating coverage files, receiving user options, including a coverage basis, a report basis, and a defined coverage, calculating coverage impact and new overall coverage using the defined coverage and coverage files, and ranking each report basis according to coverage impact of each coverage basis.

Abstract: Systems and methods are disclosed for testing dies in a stack of dies and inserting a repair circuit which, when enabled, compensates for a delay defect in the die stack. Intra-die and inter-die slack values are determined to establish which die or dies in the die stack would benefit from the insertion of a repair circuit.

Abstract: An embodiment is method comprising attaching a first die and a second die to a first surface of a first interposer using respective ones of first conductive connectors coupled to respective first surfaces of the first die and the second die; attaching a third die and a fourth die to a second surface of the first interposer using respective ones of second conductive connectors, the second surface of the first interposer being opposite the first surface of the interposer; and attaching the first die and the second die to a substrate using respective ones of third conductive connectors coupled to respective second surfaces of the first die and the second die.

Abstract: A test circuitry configured to test for transition delay defects in inter-die interconnects is disclosed. In one aspect, the test circuitry comprises an input port configured to receive a test data value and a data storage element configured to temporarily store the test data value. The test circuitry additionally comprises a second inter-die interconnect configured to be electrically connected to a first inter-die interconnect so as to form a feedback loop for transferring the test data value from the data storage element back to the data storage element. The test circuitry additionally comprises a data conditioner configured to condition the fed back test data value so as to make it distinguishable from the stored test data value. The test circuitry additionally comprises a clock pulse generator configured to generate a delayed clock pulse.

Abstract: The present disclosure relates to a method of routing probe pads to micro-bumps of an interposer. An interposer is provided having target micro-bumps and probe pads. The probe pads are initially unassigned. Target micro-bump locations and probe pad locations are obtained. Possible route assignments from the probe pads to the target micro-bumps are obtained. Costs are developed for the possible route assignments at least partially according to the target micro-bump locations and the probe pad locations. Final assignments are selected from the possible assignments according to the costs.

Abstract: A structure comprises a first die, a second die, an interposer, a third die, and a fourth die. The first die and the second die each have a first surface and a second surface. First conductive connectors are coupled to the first surfaces of the first and second dies, and second conductive connectors are coupled to the second surfaces of the first and second dies. The interposer is over the first and second dies. A first surface of the interposer is coupled to the first conductive connectors, and a second surface of the interposer is coupled to third conductive connectors. The third and fourth dies are over the interposer and are coupled to the third conductive connectors. The first die is communicatively coupled to the second die through the interposer, and/or the third die is communicatively coupled to the fourth die through the interposer.

Abstract: A circuit includes a plurality of scan chains each including a plurality of scan blocks. Each scan block includes a storage element and a switching device having an output directly coupled to an input of the storage element. The switching device has a first input configured to receive an output of a storage element in a different scan chain from the scan chain in which the switching device is disposed and a second input configured to receive one of a function logic output signal or a scan input signal. The switching device is configured to selectively couple the first input or the second input to the input of the storage element.