Abstract: A single photon detector includes a superconductor strip biased near its critical current. The superconductor strip provides a discernible output signal upon absorption of a single incident photon. In one example, the superconductor is a strip of NbN (niobium nitride). In another example, the superconductor strip meanders to increase its probability of receiving a photon from a light source. The single-photon detector is suitable for a variety of applications including free-space and satellite communications, quantum communications, quantum cryptography, weak luminescence, and semiconductor device testing.

Abstract: A system and method for calibration of a commercial semiconductor test system (tester). The system receives a synchronization signal from the tester and detects light emission from a device under test (DUT). The system then compares the timing and characteristics of the light emission to the synchronization signal to obtain a delay timing and signal change caused by intermediate elements of the tester. The delay timing and signal change are used to calibrate the various channels of the tester. Also described are various designs for DUT's to obtained enhanced accuracy of the delay timing. Further, a system and method are described for reconstruction of a test signal and study of the effects of intermediate elements of the tester on the shape of the test signal.

Abstract: Systems and methods consistent with principles of the present invention allow contactless measurements of voltage characteristics of dynamic electrical signals in integrated circuits. The invention utilizes a signal analysis circuit, such as a voltage comparator, disposed with the circuit under test, which is optically coupled with the external timing measurement equipment. The signal analysis circuit changes its state depending on the characteristics of the measured electrical signal applied thereto. The changes in the condition of the signal analysis circuit are sensed by the external timing measurement equipment provided outside the circuit under test. To this end, the signal analysis circuit is optically coupled with the external measurement equipment registering specific changes in the condition of the signal analysis circuit.

Abstract: A system, apparatus, and method for analyzing photon emission data to discriminate between photons emitted by transistors and photons emitted by background sources. The analysis involves spatial and/or temporal correlation of photon emissions. After correlation, the analysis may further involve obtaining a likelihood that the correlated photons were emitted by a transistor. After correlation, the analysis may also further involve assigning a weight to individual photon emissions as a function of the correlation. The weight, in some instances, reflecting a likelihood that the photons were emitted by a transistor. The analysis may further involve automatically identifying transistors in a photon emission image.

Abstract: A combination cooling plate and micro-spray cooling system beneficial for use in testers of electrically stimulated integrated circuit chips is disclosed. The system includes a transparent heat spreader and micro-spray heads disposed about the heat spreader. The spray heads spray cooling liquid onto a periphery of said heat spreader so as to remove heat from the chip. Alternatively, and micro-spray heads are provided inside the cooling plate holder so as to spray cooling liquid inside the interior of the holder so that the holder is cooled. The holder is in physical contact with the heat spreader, so that as the holder is cooled by the spray, heat is removed from the heat spreader, and thereby from the chip.

Abstract: A universal diagnostic platform (UDP) is described which incorporates several measurement modules for testing a device under test (DUT). Users can switch between measurement modules without removing the DUT. The UDP employs a common fixturing and software system for all the modules.

Abstract: Systems and methods consistent with principles of the present invention alow contactless measuring of various kinds of electrical activity within an integrated circuit. The invention can be used for high-bandwidth, at speed testing of various devices on a wafer during the various stages of device processing, or on packaged parts at the end of the manufacturing cycle. Power is applied to the test circuit using conventional mechanical probes or other means, such as CW laser light applied to a photoreceiver provided on the test circuit. The electrical test signal is introduced into the test circuit by stimulating the circuit using a contactless method, such as by directing the output of one or more modelocked lasers onto high-speed receivers on the circuit, or by using a high-speed pulsed diode laser.

Abstract: A method and system of testing integrated circuits (IC) via optical coupling. The optical system includes an optical fiber, fixture and focussing element. In addition, channels are provided in the fixture mounted on the integrated circuit to accommodate the optical system. The fixture acts as a heat sink. As such, one or more photosensitive elements/targets on the integrated circuit are probed using light that is brought to a focus on each target site. The light causes latching of data into the integrated circuit (which is operating under influence of a test program) and formation of a test pattern output from the integrated circuit that is used to confirm proper functioning of the IC.

Abstract: A laser beam is used to probe an integrated circuit device under test. A single laser provides a single laser pulse which is divided into two pulses, both of which are incident upon the device under test. After the two pulses interact with the device under test, the two pulses are separated and detected by two photo detectors. The electrical signals output by the photo detectors are then subtracted, which cancels out any common mode noise induced on both pulses including noise due to mechanical vibration of the device under test and also any noise from the laser. The difference signal can be used to reproduce a time varying signal in the device under test.