Fault Coexistence and Grading Aware TSV Test based on Delay Feature

Screening out the defects in the TSV manufacturing process and eliminating the resistive open fault and leakage fault as early as possible are beneficial to improve the yield and reliability of 3D ICs. The existing prebond test methods are confined to the test accuracy and de- tection range, especially the test confusion prob- lem and the lack of diagnosable ability under the coexistence of multiple faults. Based on the uc- tuation of delay feature caused by faults, a kind of fault coexistence and grading aware TSV test method is proposed to enhance the yield and reli- ability of TSVs in this paper. The reference TSV and the TSV under test are input with test stim- uli simultaneously. Furthermore, the designed delay extraction circuit is utilized to generate the rising edge and the falling edge separately and additional fault grading circuit can be enriched according to the test requirements. Finally, a one bit comparator at the capture end is used to detect whether two pulse signals arrive simul- taneously, so as to determine whether there is a fault and the type of fault. The simulation results indicate that the detection range of resistive open fault is more than 281 , and the detection range of leakage fault is less than 223 M , which is bet- ter than most existing methods. While effective- ly solving resistive open fault and leakage fault, it can also successfully deal with the coexistence of two kinds of faults and achieve a 5-level fault grading ability with relatively low area overhead.

Increase of the particle hit rate in laser single particle mass spectrometer by pulse delayed extraction technology

Single particle mass spectrometer is the instrument providing a plenty of valuable information on chemical and physical parameters of individual particles in real time. One of the main performance criteria of the instrument is the efficiency of particles detection (hit rate). Most of SPMS instruments use DC extraction, when the stationary high voltage is applied to the extraction electrodes. As the aerosol particles initially carry a certain charge, they can be deflected by this electric field thus decreasing the hit rate. It was realized in this work, that the delay extraction technique can eliminate the stochastic dispersion of the particles beam caused by their deflection in the stationary electric field. As the result, the hit rate of the instrument can be significantly improved. Also, as the effect of deflection in the electric field is mass dependent, it can cause the distortion of the measured size distribution of the particles. Hence, the delay extraction can bring the measured distribution closer to the real one. Thus, the delay extraction technique provides not only mass resolution improvement, but also increases the hit rate. The gain in the hit rate depends on the type of the particles. It can be two orders of magnitude for model particles, and up to 2–4 times for real particles. In the present work we report experiments and results showing the effect of the delay extraction on the particles beam divergence caused by particles charge, the hit rate improvement and the effect of the delay extraction on the measured particles size distribution.