Abstract: A method and system for aligning a DUT image for testing. The alignment is performed by obtaining an optical image of the DUT from an optical system; obtaining a computer aided design (CAD) data having CAD layers of the DUT; constructing a CAD image of the DUT by overlaying the CAD layers; operating on the CAD image to generate a synthetic image simulating an optical image of the DUT; generating a difference image by comparing the optical image to the synthetic image; and, varying parameters of the synthetic image so as to minimize the difference image.

Abstract: A method and system for aligning a DUT image for testing. The alignment is performed by obtaining an optical image of the DUT from an optical system; obtaining a computer aided design (CAD) data having CAD layers of the DUT; constructing a CAD image of the DUT by overlaying the CAD layers; operating on the CAD image to generate a synthetic image simulating an optical image of the DUT; generating a difference image by comparing the optical image to the synthetic image; and, varying parameters of the synthetic image so as to minimize the difference image.

Abstract: An IREM image of an IC is obtained. The emission intensity at each emission site is measured/calculated and is compared to reference intensity. The calculated intensity may be plotted against reference intensities. In general, the majority of the plotted intensities would lie in a given range within a straight line. However, for devices that exhibit an abnormal emission, the plot would result in an easily observable deviation from the line. The calculated intensity is used to make a determination of logical “1” or “0” for each device, which is automatically stored together with the corresponding test vector. The calculated logical states are then tabulated and compared against tabulation of reference logical states.

Abstract: A method and system for quickly informing a backup unit that a primary unit has failed. Normally an exception handler is activated when a software failure occurs and network controller chips or the ASIC interface to a signal bus can operate even though there is a software failure. A software failure notification packet is programmed and stored in a location that is not affected by a software system failure. When a software failure occurs, control is shifted to the exception handler. The exception handler sends a pre-established and pre-addressed packet to the network controller card which transmits this packet to the backup unit. Upon receipt of the packet, the backup unit goes into operation. In some alternate embodiments that include multiple line cards in a single unit, the exception handler sends a signal to a backup unit via a signal bus or a data bus.

Abstract: A method for isolating the emitting devices may be applied to various emission and laser microscopy systems. A point spread function is convolved with CAD data of devices involved in the emission. The calculated signal intensity of the devices is varied until the difference between the calculated signal and the measured signal provides best fit. The best fit is performed for each on/off state for all configurations of the involved devices. The variance of the best curve fit for all of the configurations is used to assign probability to each state. The best fit indicates the correct state of each of the involved devices, thereby indicating which devices emit. At times, when the transistors are extremely close, a weighted solution is calculated. The weights are based on the probability of each solution.

Abstract: An IREM image of an IC is obtained. The emission intensity at each emission site is measured/calculated and is compared to reference intensity. The calculated intensity may be plotted against reference intensities. In general, the majority of the plotted intensities would lie in a given range within a straight line. However, for devices that exhibit an abnormal emission, the plot would result in an easily observable deviation from the line. The calculated intensity is used to make a determination of logical “1” or “0” for each device, which is automatically stored together with the corresponding test vector. The calculated logical states are then tabulated and compared against tabulation of reference logical states.

Abstract: A method and system for quickly informing a backup unit that a primary unit has failed. Normally an exception handler is activated when a software failure occurs and network controller chips or the ASIC interface to a signal bus can operate even though there is a software failure. A software failure notification packet is programmed and stored in a location that is not affected by a software system failure. When a software failure occurs, control is shifted to the exception handler. The exception handler sends a pre-established and pre-addressed packet to the network controller card which transmits this packet to the backup unit. Upon receipt of the packet, the backup unit goes into operation. In some alternate embodiments that include multiple line cards in a single unit, the exception handler sends a signal to a backup unit via a signal bus or a data bus.

Abstract: A method and system for quickly informing a backup unit that a primary unit has failed. Normally an exception handler is activated when a software failure occurs and network controller chips or the ASIC interface to a signal bus can operate even though there is a software failure. A software failure notification packet is programmed and stored in a location that is not affected by a software system failure. When a software failure occurs, control is shifted to the exception handler. The exception handler sends a pre-established and pre-addressed packet to the network controller card which transmits this packet to the backup unit. Upon receipt of the packet, the backup unit goes into operation. In some alternate embodiments that include multiple line cards in a single unit, the exception handler sends a signal to a backup unit via a signal bus or a data bus.

Abstract: A method for isolating the emitting devices may be applied to various emission and laser microscopy systems. A point spread function is convolved with CAD data of devices involved in the emission. The calculated signal intensity of the devices is varied until the difference between the calculated signal and the measured signal provides best fit. The best fit is performed for each on/off state for all configurations of the involved devices. The variance of the best curve fit for all of the configurations is used to assign probability to each state. The best fit indicates the correct state of each of the involved devices, thereby indicating which devices emit. At times, when the transistors are extremely close, a weighted solution is calculated. The weights are based on the probability of each solution.

Abstract: A light emission microscope includes a low temperature detector array which receives light through a room temperature projection optics system from a device under test. A cold aperture including a movable cold stop and a cryogenic filter absorbs unwanted thermal radiation emitted by the optics system. In one embodiment, a high resolution CCD camera can be used with the low temperature detector array and camera with a computer-controlled mirror providing emitted light to both cameras.

Abstract: Vibration damping apparatus for vibrating environment such as a light emission microscope and an integrated circuit test head includes a rigid member with remotely controlled clamping apparatus attached to spaced portions of the member. The clamping apparatus engage the microscope and the test head for reducing vibrations, and the clamping apparatus can be readily deactivated for moving the microscope or the test head for alignment purposes. Advantageously, two or more rigid members including pneumatic cylinders can be positioned around the device under test while permitting the use of mechanical probes for engaging nodes of an integrated circuit for test purposes.

Abstract: A light emission microscope includes a low temperature detector array which receives light through a room temperature projection optics system from a device under test. A cold aperture including a movable cold stop and a cryogenic filter absorbs unwanted thermal radiation emitted by the optics system. In one embodiment, a high resolution CCD camera can be used with the low temperature detector array and camera with a computer-controlled mirror providing emitted light to both cameras.

Abstract: An emission microscope is mounted on a transportable structure for use on a test floor and encloses or garages an entire automatic test equipment head to facilitate high-speed testing. Test procedures allow development of static/fixed defects over time. A video mask can be developed based on emission sites on known good devices so that only emission from defect sites of bad devices under test are shown.

Abstract: An emission microscope includes integrating and enhancing devices operating in parallel for optimizing the image of a scanned semiconductor device. Integration is terminated when sufficient clarity is acquired. The system further incorporates adaptive histogram matching using a noise distribution curve. Those pixels not meeting a predetermined intensity level are deleted to further enhance image display.

Abstract: An emission microscope providing time resolution and high sensitivity to the viewing of light emitted from semiconductor devices is described. The present invention comprises a microscope optic system coupled to an image intensifier. An integrated circuit is viewed with the microscope optics and is stimulated with current flow. As a result of different phenomena, (oxide current, avalanching, and forward biased p-n junctions) light is emitted from the circuit. The image intensifier magnifies the light signal produced by the microscope optics. The output of the intensifier is coupled to a solid-state (CID or CCD) camera. The CID camera outputs a TV signal which is coupled to an image processing computer. The image processing computer controls image enhancement as well as noise reduction. The image processing computer is coupled to an output such as a monitor, a recorder, a printer, or any other suitable display.