Related Reliability Problems Research Articles

DRHEFT: Deadline-Constrained Reliability-Aware HEFT Algorithm for Real-Time Heterogeneous MPSoC Systems

Heterogeneous multiprocessor system-on-chips (MPSoCs) are suitable platforms for real-time embedded applications that require powerful parallel processing capability as well as low power consumption. For such applications, soft-error reliability (SER) due to transient faults and lifetime reliability (LTR) due to permanent faults are both key concerns. There have been several efforts in the literature oriented toward related reliability problems. However, most existing techniques only concentrate on improving one of the two reliability metrics, which are not suitable for embedded systems deployed in critical applications in need of a long lifetime as well as a reliable execution. This article develops a novel heterogeneous earliest-finish-time (HEFT)-based algorithm to maximize SER and LTR simultaneously under the real-time constraint for dependent tasks executing on heterogeneous MPSoC systems. More specifically, a new deadline-constrained reliability-aware HEFT algorithm, namely DRHEFT, is proposed, which seeks for the best SER–LTR tradeoff solutions through using fuzzy dominance to evaluate the relative fitness values of candidate solutions. The extensive experiments on real-life benchmarks as well as synthetic applications demonstrate that DRHEFT is capable of achieving better SER–LTR tradeoff solutions with higher hypervolume and less computation cost when compared with the state-of-the-art approaches.

Solving 28 nm I/O circuit reliability issue due to IC design weakness

Integrated circuit (IC) reliability failure at field presents significant cost to both manufacturer and consumer. This paper targets reliability issue due to IC design weakness, presenting a case of 28 nm Input/Output (I/O) circuit reliability failure, and shows a complete work flow, starting from root cause identification using Final Test (FT) and failure analysis (FA), and ending with design retrofit to solve the issue. The work flow solves a 28 nm I/O reliability issue successfully (a narrow metal leads to EOS at field, and design retrofit is done to enlarge metal's current carrying capability). The work flow is applicable to solve general design related reliability problems.

Kinetics of Charge‐Transfer Reactions at Nanoscopic Electrochemical Interfaces

AbstractAfter several decades of intensive studies, the questions about the magnitudes of rate constants of rapid heterogeneous electron transfer (ET) and ion transfer (IT) reactions remain open. The fabrication of nanometer‐sized metal electrodes and nanopipets enabled electrochemical studies of rapid charge transfer processes at solid/liquid and liquid/liquid nanointerfaces. The nanoelectrochemical techniques offer numerous advantages such as fast mass‐transfer rate and simplified analysis of data obtained under steady‐state conditions. At the same time, kinetic data obtained at nanointerfaces may be affected by double layer effects, deviations from classical electrochemical theory, and other size‐related phenomena. Nanoelectrochemical measurements are also plagued by difficulties in characterizing nanometer‐sized interfaces and conductor/insulator boundaries. In this review, we discuss the results of fast electron and ion transfer kinetics measurements at nanointerfaces, along with related reliability problems and some approaches to fixing them.

Comparison of positive and negative bias-temperature instability on MOSFETs with HfO 2/LaO x and HfO 2/AlO x dielectric stacks

The modified charge-pumping (CP) techniques were applied to characterize the trap distribution as well as its related reliability problems for MOSFETs with HfO 2/LaO x and HfO 2/AlO x high-κ gate stacks. It is found that the positive bias temperature (PBT) and negative bias temperature (NBT) stresses would cause different kinds of traps generated at different locations. The negative bias causes even more damage than positive bias on nMOS devices. The generation of N it caused by BT stress is uniform through whole channel, no matter positive bias or negative bias. The generation of border trap ( N bt) caused by NBT stress is much more and deeper than that caused by PBT one.

Driving Mechanisms of Delamination Related Reliability Problems in Exposed Pad Packages

Exposed pad packages were introduced in the late 1980s and early 1990s because of their excellent thermal and electrical performance. Despite these advantages, the exposed pad packages experience a lot of thermo-hygro-mechanical related reliability problems during qualification and testing. Examples are die lift, which occurs predominantly after moisture sensitivity level conditions, and die-attach to leadframe delamination leading to downbond stitch breaks during temperature cycling. In this chapter, nonlinear finite element (FE) models using fracture mechanics based J-integral calculations are used to assess the reliability problems of the exposed pad package family. Using the parametric FE models any geometrical and material effects can be explored to their impact on the occurrence diepad delamination, and dielift. For instance the impact of diepad size is found to be of much less importance as the impact of die thickness is. Using the fracture mechanics approach, the starting location for the delamination from thermo-hygro-mechanical point of view is deducted. The results indicate that when diepad delamination is present, cracks are likely to grow beneath the die and dielift will occur. The interaction between dielift and other failure modes, such as lifted ball bonds, are not found to be very significant. The FE models are combined with simulation-based optimization methods to deduct design guidelines for optimal reliability of the exposed pad family.

Identifying and Reducing Scaling Problems in Solar Hot Water Systems

In areas with hard water, scaling can reduce the reliability of solar hot water (SHW) systems. Common reliability problems associated with scaling are both mechanical (collector freeze damage, clogged passages, premature failure of pumps and valves) and thermal (efficiency degradation). A mechanistic and a mathematical scaling rate model are presented. Results from controlled experiments investigating the affect of key water chemistry and heat transfer parameters on the scaling rate are summarized. The implications of these results for designing SHW systems for scaling environments are discussed. Most importantly, indirect systems where the potable water side of the heat exchanger is integrated into the storage tank wall, such as in a wrap-around heat exchanger, are shown to be the most mechanically and thermally reliable systems for scaling environments. A new version of the software SolScale is discussed, which is intended to aid in the design of SHW systems to reduce scaling related reliability problems.