Nxp Usa, Inc.

Freescale Semiconductor,inc.

Dcg Systems Gmbh

Kent Erington

Daniel Joseph Bodoh

Theodore R Lundquist

Keith Serrels

Kristofor J Dickson

John E Asquith

Method to extract timing diagrams from synchronized single- or two-photon pulsed LADA by spatially positioning the incident laser beam on circuit feature of interest, temporally scanning the arrival time of the laser pulse with respect to the tester clock or the loop length trigger signal, then recording the magnitude and sign of the resulting fail rate signature per laser pulse arrival time. A Single-Photon Laser-Assisted Device Alteration apparatus applies picosecond laser pulses of wavelength having photon energy equal to or greater than the silicon band-gap. A Two-Photon Laser-Assisted Device Alteration apparatus applies femtosecond laser pulses of wavelength having photon energy equal to or greater than half the silicon band-gap at the area of interest. The laser pulses are synchronized with test vectors so that pass/fail ratios can be altered using either the single-photon or the two-photon absorption effect. A sequence of synthetic images with error data illustrates timing sensitive locations.

Synchronized pulsed LADA for the simultaneous acquisition of timing diagrams and laser-induced upsets

Digital testing is performed on an integrated circuit while radiation upsets are induced at locations of the integrated circuit. For each digital test, a determination is made as to whether there is a variation in the output of the digital test from an expected output of the digital test. If there is variation, a time of the variation is indicated. In one example, a location of a defect in the digital circuit can be determined from the times of the variations. In other embodiments, a mapping of the digital circuit can be made from the times.

Digital tests with radiation induced upsets

A pulse laser test system including a conditioning pulse circuit, a probe pulse circuit, a pulse laser, a trigger mode controller, and a laser pulse modulator. The conditioning pulse circuit provides asynchronous conditioning trigger pulses at a selected rate. The probe pulse circuit provides a synchronized probe trigger pulse. The trigger mode controller selects the probe pulse circuit while the synchronized probe trigger pulse is provided causing the pulse laser to provide a synchronized probe laser pulse, and otherwise selects the output of the conditioning pulse circuit causing the pulse laser to provide asynchronous conditioning laser pulses. The laser pulse modulator has an optical input coupled to the laser output of the pulse laser, has a gating input receiving a gate signal from the trigger mode controller, and has an optical output that provides laser pulses passed from the pulse laser while the gate signal is asserted.

System and method of multiplexing laser triggers and optically selecting multiplexed laser pulses for laser assisted device alteration testing of semiconductor device

A method of time resolved radiation assisted device alteration testing of a semiconductor circuit which includes performing spatially resolved radiation assisted circuit testing on the semiconductor circuit while applying a test pattern to determine a pass-fail modulation location, asynchronously scanning the semiconductor circuit with radiation while repeatedly applying the test pattern and providing pass-fail results, combining corresponding pass-fail results provided during the asynchronously scanning to determine a shifted pass-fail modulation indication, determining time shift information between the pass-fail modulation location and the shifted pass-fail modulation indication, and identifying at least one of the test vectors based on the time shift information. The radiation may be a continuous wave laser beam. The time shift information may be determined by scanning an image, incorporating graphics into the image indicating the pass-fail modulation location and the shifted pass-fail modulation indication, and measuring a pixel shift on the scanned image.

Time resolved radiation assisted device alteration

A method of locating a defect of a failed semiconductor device which includes applying a test pattern to the failed semiconductor device and providing failed semiconductor device test responses as a pass signature, applying radiation to each of multiple locations of circuitry of a correlation semiconductor device with sufficient energy to induce a fault in the circuitry, applying the test pattern to the correlation semiconductor device while the radiation is applied to the location and comparing correlation semiconductor device test responses with the pass signature for each location, and determining a defect location of the failed semiconductor device in which correlation semiconductor device test responses at least nearly match the pass signature. The radiation may be a laser beam. The method may include determining an exact match or a near match based on a high correlation result. Asynchronous scanning may be used to provide timing information.

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Austin, TX, United States of America

Kent Erington