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In three-dimensional integrated circuits (3D-ICs), through silicon via (TSV) is a critical technique in providing vertical connections. However, yield is one of the key obstacles to adopt the TSV-based 3D-ICs technology in the industry. Various fault-tolerance structures using redundant TSVs to repair faulty functional TSVs have been proposed in the literature for yield and reliability enhancement. However, the TSV repair paths under delay constraint cannot always be generated due to the lack of appropriate repair algorithms. In this article, we propose an effective TSV repair strategy for the router-based TSV redundancy architecture, taking into account the delay overhead. First, we prove that the router-based fault-tolerance structure configuration (RFSC) with the delay constraint is equivalent to the length-bounded multicommodity flow (LBMCF) problem. Then, an integer linear programming (ILP) formulation with acceptable scalability is presented to solve the LBMCF problem. The experimental results demonstrate that, compared with state-of-the-art fault-tolerance designs, the proposed ILP model can provide higher yield and lower delay overhead. [ABSTRACT FROM AUTHOR]

Aggressive technology scaling makes modern advanced SRAMs more and more vulnerable to soft errors such as single-node upsets (SNUs) and double-node upsets (DNUs). This paper proposes two SRAM cells; the first one is called Quadruple Cross-Coupled SRAM (QCCS) and the second one is called Sextuple Cross-Coupled SRAM (SCCS). The QCCS cell comprises four cross-coupled input-split inverters to keep stored values, and provides self-recoverability from SNUs at low cost. To improve reliability, the SCCS cell uses six cross-coupled input-split inverters to construct a large error-interceptive feedback loop and hence robustly keep stored values. The SCCS cell can self-recover from all possible SNUs and one part of DNUs; for remaining DNUs, a node-separation mechanism is used to avoid their occurrence. Simulation results demonstrate the robustness of the proposed cells. Moreover, compared with the state-of-the-art hardened cells, i.e., NASA13T, RHBD12T, We-Quatro, Zhang14T, QUCCE12T, DNUSRM, QCCM10T, QCCM12T, S4P8N, and S8P4N, the QCCS cell reduces read access time by 17%, write access time by 19%, power dissipation by 4% and silicon area overhead by 10% on average, while the SCCS cell reduces read access time by 44% as well as write access time by 13% on average at the cost of moderate increase in power dissipation and silicon area overhead. [ABSTRACT FROM AUTHOR]

True random number generators (TRNGs) play an important role in encryption systems. In this brief, a novel method of generating true random numbers on a field-programmable gate array (FPGA) is proposed based on the random jitter of a multi-stage feedback ring oscillator (MSFRO) as the entropy source. Based on the traditional ring oscillator, a multi-stage feedback structure is added to enlarge the range of clock jitter, and improve the frequency of clock sampling and the randomness of the entropy source. Different from the traditional clock sampling structure, we use the clock jitter signal generated by the MSFRO to sample the clock signal generated by the phase-locked loop (PLL) of the FPGA. The obtained output value is operated by XOR to reduce the deviation of the output value and improve its randomness. The TRNG is implemented in Xilinx Virtex-6 FPGA, which has low hardware resource consumption and high throughput. The entropy source classification, hardware resources and throughput are compared with those of existing TRNGs. The results showed that the proposed TRNG only consumed 24 LUTs and 2 DFFs. Compared with other TRNGs, this design has very low hardware resource consumption and its throughput is up to 290 Mbps. The random bit sequence generated by this TRNG passes the NIST SP800-22 test and the NIST SP800-90B test. [ABSTRACT FROM AUTHOR]

Due to the winding level of the thinned wafers and the surface roughness of silicon dies, the through-silicon vias (TSVs) defect tend to be clustered, reducing the yield of 3-D integrated circuit significantly. To tackle this fault clustering problem, the existing TSV repair methods adopt the TSV redundancy idea, which brings a major cost to 3-D integration. In this brief, a honeycomb-TDMA TSV design is proposed to mitigate the impact of multiple clustered faults without the need of redundant TSVs (RTSVs), thereby decreasing the area overhead and enhances the yield. The yield of the honeycomb-TDMA architecture can achieve 91.38%–99.67% for different benchmark circuits from IWLS 2005, which has the highest yield. Furthermore, our design achieves total additional hardware (timing delay overhead) reduction by 83.70%–86.85% (46.01%–55.96%), 66.89%–73.25% (29.41%–38.49%), 68.02%–74.20% (41.40%–52.20%), 60.60%–68.18% (18.09%–33.18%), and 75.86%–80.52% (3.05%–20.91%), respectively, compared with router-based, ring-based, group-based, cellular-based, and honeycomb-based methods. Therefore, the proposed architecture is the best choice in terms of yields, hardware overhead, and timing delay. [ABSTRACT FROM AUTHOR]

When the feature size of integrated circuits (ICs) reaches nanometer, nano contaminant particles (CPs) on the surface of semi-finished devices during processing may cause serious device defects, while effective real-time CP detection techniques are still unavailable, especially when the CPs are of low concentration. Using a gold interdigitated electrode fabricated on a ceramics substrate, a sensitive sensor for ultra-trace nano CP detection in cleaning fluids is developed, which employs an optimized detection signal integrating the nanofluidic enrichment of nanoparticles (NPs) into interfacial capacitance measurement. The detection can achieve a limit of detection of 102 particles/mL with a response time of 30 s. The logarithmic linear range of this sensor reaches (102 - 107) particles/mL for CPs of 10 nm in grain diameter, which can meet the test demand of practical concentration. This sensor has capability to detect CPs of different material and size, and the operation is real-time and nondestructive. In addition, it is demonstrated to work reliably in solutions with different conductivity. The detection protocol is simple, and the sensor as well as the impedance analyzer for test also has advantages in portability and cost efficiency for industrial-scale on line application. This work provides a feasible and promising approach for IC fabrication’s quality evaluation through ultra-trace nano CP detection in used cleaning liquid samples. [ABSTRACT FROM AUTHOR]

In this brief, a non-invasive online solution for 2.5D IC based on distributed pulse shrinking is proposed to test the faults of interconnects. Furthermore, a regression model based on artificial neural network (ANN) is proposed in order to judge whether the interconnects are faulty and quantify the degree of the faults in real time by online monitoring the delay of interconnects. Experiments on defect detection are presented through HSPICE simulation with realistic models for 45nm CMOS technology. The results show that the proposed method has features including: high resolution, low area overhead, high robustness, and be able to predict the class and the fault size. [ABSTRACT FROM AUTHOR]

Due to the winding level of the thinned wafers and the surface roughness of silicon dies, the quality of through-silicon vias (TSVs) varies during the fabrication and bonding process. If one TSV exhibits a defect during its manufacturing process, the probability of multiple defects occurring in the TSVs neighboring the faulty TSV increases, i.e., the TSV defects tend to be clustered, which significantly reduces the yield of 3-D integrated circuit. To resolve the clustered TSV faults, router-based, ring-based, group-based, and cellular-based redundant TSV (RTSV) architectures were proposed. However, the repair rate is low and the hardware overhead as well as delay overhead is high. In this article, we propose a honeycomb-based RTSV architecture to utilize the area and delay more efficiently as well as to maintain high yield. The simulation results show that the proposed architecture has a 99.84% repair rate for uniform faults and an 81.42% repair rate for highly clustered faults. The proposed design achieves a 51.66% reduction of hardware overhead compared with the router-based design and a 20.69%, 46.93%, 34.17%, and 11.15% reduction of total delay compared with ring-based, router-based, group-based, and cellular-based methods, respectively. [ABSTRACT FROM AUTHOR]

In this brief, a cobweb-based redundant through-silicon-via (TSV) design is proposed with efficient hardware as well as high repair rate to repair clustered faulty TSVs (FTSVs). The experimental simulation results demonstrate that for highly clustered faults, the repair rate of the proposed RTSV method is 48.59% and 1.75% higher than that of the ring-based and router-based RTSV methods, respectively. Furthermore, the proposed design can achieve 63.93% and 16.34% hardware reductions compared with the router-based and the ring-based design, respectively. [ABSTRACT FROM AUTHOR]

In nano-scale CMOS technologies, storage cells such as latches are becoming increasingly sensitive to triple-node-upset (TNU) errors caused by harsh radiation effects. In the context of information assurance through redundant design, this article proposes a novel low-cost and TNU on-line self-recoverable latch design which is robust against harsh radiation effects. The latch mainly consists of a series of mutually interlocked 3-input Muller C-elements (CEs) that forms a circular structure. The output of any CE in the latch respectively feeds back to one input of some specified downstream CEs, making the latch completely self-recoverable from any possible TNU, i.e., the latch is completely TNU-resilient. Simulation results demonstrate the complete TNU-resiliency of the proposed latch. In addition, due to the use of fewer transistors and a high-speed path, the proposed latch reduces the delay-power-area product by approximately 91 percent compared with the state-of-the-art TNU hardened latch (TNUHL), which cannot provide a complete TNU-resiliency. [ABSTRACT FROM AUTHOR]

Since the physical defects such as resistive open and leakage in through silicon vias (TSVs) caused by immature manufacturing techniques tend to undermine the reliability and yield of 3-D integrated circuits, it is very important to test the TSV as early as possible in the fabrication process. There are some shortcomings in the existing prebond TSV test techniques, such as incomprehensive fault coverage, large area overhead, and additional test time. To overcome these problems, a noninvasive solution for prebond TSV test based on pulse shrinking is proposed in this paper. This method makes use of the fact that defects in TSV lead to variation in the propagation delay—the rise and fall times are first transformed into pulse width, and the pulse shrinking technique is used to digitize the pulse width into a digital code which is then compared with an expected value for a fault-free TSV. Experiments on defect detection are carried out using HSPICE simulations with realistic models for 45-nm CMOS technology. The results show that the proposed method performs better than the existing methods in terms of fault coverage, area overhead, and test time. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for accurate characterization of Single Event Transient (SET) propagation in SRAM-based Field Programmable Gate Arrays (FPGAs): both generation and measurement of SETs are implemented on chip, respectively connected to input port and output port of the test combinational paths. The scheme we developed is mainly based on two circuits: 1) the one is a SET generating circuit for on-chip producing an adjustable pulse with a temporal resolution of near 100 ps; 2) the other is a SET measuring circuit for on-chip measuring pulses with a temporal resolution of near 80 ps and the ability to detect narrow transient pulses of about 300 ps. Based on above methodology, we investigate the effect of traversing seven logic chains with different gate types and multiple chain lengths on pulse widths, i.e., Propagation Induced Pulse Distorting (PIPD). Results demonstrate, when SETs propagate along Look Up Tables (LUTs) in Virtex-6 FPGAs, there is a broadening for negative SETs (1-0-1) while not for positive SETs (0-1-0); in addition, pulse width has no impact on PIPD, and which is linearly proportional to the number of stages. [ABSTRACT FROM AUTHOR]