Modern reliability assurance of integrated circuits—A strategy based on technology capability assessment and production reproducibility control

Technological innovations provide integrated circuits of increased functionality and complexity, and modern design tools facilitate a new multiplicity of products, such as application-specific products (ASICs). Traditional qualification procedures cannot keep pace with this evolution with respect to requirements of product reliability, ability of qualifying the multiplicity of future products, and market demands for saving cost and time. A further development of a reliability assurance concept, which will be discussed here, considers design tools, basic product elements, materials, manufacturing process and controls as a ‘system’, which has to be qualified with respect to the consistency and efficiency of all of the implemented reliability assurance measures. The concept is based on the manufacturer's ‘system’ knowledge and responsibility. It is compatible with the relevant requirements of ISO 9000 and recent military standard proposals. The procedure is applied to commercial products. The main part of this concept is the qualification of the manufacturing technology. The procedure is organized as a continuous process starting at the concept phase of a new technology and its pilot product. The various steps then follow the development, the pre-series and series production phases. The reliability aspects concentrate on the physical properties of product elements relevant to their stability and endurance, i.e. the potential failure mechanisms and their root causes as reliability risks. Thus a major part of reliability testing for the qualification of the pilot product of a new technology can be performed without the use of the final product version. The benefits derivable from this approach are savings in time and cost as well as the capability to handle future product multiplicity.     

Software qualification in safety applications

The developers of safety-critical instrumentation and control systems must qualify the design of the components used, including the software in the embedded computer systems, in order to ensure that the component can be trusted to perform its safety function under the full range of operating conditions. There are well known ways to qualify analog systems using the facts that: (1) they are built from standard modules with known properties; (2) design documents are available and described in a well understood language; (3) the performance of the component is constrained by physics; and (4) physics models exist to predict the performance. These properties are not generally available for qualifying software, and one must fall back on extensive testing and qualification of the design process. Neither of these is completely satisfactory.The research reported here is exploring an alternative approach that is intended to permit qualification for an important subset of instrumentation software. The research goal is to determine if a combination of static analysis and limited testing can be used to qualify a class of simple, but practical, computer-based instrumentation components for safety application. These components are of roughly the complexity of a motion detector alarm controller. This goal is accomplished by identifying design constraints that enable meaningful analysis and testing. Once such design constraints are identified, digital systems can be designed to allow for analysis and testing, or existing systems may be tested for conformance to the design constraints as a first step in a qualification process. This will considerably reduce the cost and monetary risk involved in qualifying commercial components for safety-critical service.     

Validation of solid dosage forms the FDA view

Abstract

In May 1987 the United States Food and Drug Administration published the final version of a guideline for process validation for pharmaceutical manufacturing. The document incorporated the comments from the pharmaceutical industry gathered after the publication of three draft versions in 1983, 1984 and 1986.

The presentation will cover the current definition of process validation as well as terms such as “worse case” and “installation qualification”.

The stages of process validation will be discussed including the written plan (protocol): records to be maintained; suitability of raw materials; equipment performance qualification; the number of runs required; and acceptance criteria.

Specifics for solid dosage forms will be presented along with details on batch record in instructions and establishment of acceptable range limits.

Circumstances and requirements for revalidation will be discussed as well as the validation of current finished dosage forms by retrospective validation.     

基于FAHP的军品包装外包商的选择

目的确定军品包装外包商评价指标权重。方法尝试根据军品包装外包的特殊性,建立一个包含企业绩效、生产能力、研发能力、风险、资质认证和环境条件在内的指标评价体系,用模糊层次分析法FAHP法求出军品包装外包商的评价指标权重。结果综合权重较大的4项指标分别为企业信誉、质量、质量资格认证和生产状况。其中企业信誉所占权重最大,为0.168,其次是质量,综合权重为0.096,质量资格认证和生产状况均为0.08。结论企业信誉、质量、质量资格认证和生产状况等4项指标在选择军品包装外包商时应优先考虑。     

Variance Component Calculations: Common Methods and Misapplications in the Semiconductor Industry

Calculating variance components is of utmost importance in the semiconductor industry. Often, estimates of product and process variation are needed for both qualification and improvement. Once estimates are obtained, process and product improvement efforts can proceed. In this paper, the analysis of variance (ANOVA) method is used to show how variance components are calculated correctly from a fully nested, random effects model. Due to lack of understanding and tools, other common “variance-like” calculations are often used in practice/industry, based on variances of averages, to estimate variance components. It will be shown that these calculations are misapplications of known variance formulas and provide incorrect variance component estimations. The ANOVA method will be compared to these common calculations often used in industry. The potential pitfalls often encountered with these methods will be highlighted. The adjustment factors, which correct these commonly calculated variance components to match the ANOVA method variance components, will be given and then explored. And finally, the relationships of the methods discussed herein to other nested model types will be presented. A case study will be referenced throughout the paper to show the applications of such methods.     

制充氮封存包装一体化设备研制

针对军用光电器材封存包装特点和应急保障需求,研制了军用光电器材制充氮封存包装一体化设备。介绍了制氮原理、工艺流程以及设备组成、功能特点等。大量的实践应用表明：设备运行可靠、性能优越,可现场对军用光电器材实施制充氮封存包装,实现军用光电器材的长效封存与快速启封。     

A novel accelerated moisture absorption test and characterization

Moisture plays a significant role in influencing the mechanical behavior and long-term durability of composites. With the current available testing techniques the time required for environmental qualification of polymer composites can be on the order of several years and any interruption in the test can result in a significant cost and schedule penalty. Because of these long environmental conditioning times there is a strong desire to accelerate the process to advance environmental qualification of materials for use in commercial and military aerospace structures. An accelerated humidity test technique has been developed where moisture ingression was obtained by increasing the pressure in the test chamber. A hygrothermal humidity chamber was used in combination with D₂O water to subsequently characterize the diffusion of D₂O in a carbon/epoxy composite using Nuclear Reaction Analysis (NRA). Moisture content was also measured as a function of through-thickness depth using NRA. The accelerated technique decreased the time to saturation by 80% as compared to conventional diffusion without pressure. Moisture uptake from both conventional and accelerated diffusion exposures followed typical Fickian diffusion response.     

Process Qualification

This paper offers a practical approach to process qualification based on estimating the impact on the fraction nonconforming and the sensitivity of the nonconformance rate to changes in the mean or standard deviation of the process. The methodology makes certain assumptions regarding the magnitude of the changes that might be expected in the process parameters and then computes the effect that these changes might be expected to have on the nonconformance probability and its variability. If the impact is within acceptable limits, then the process is considered robust enough to be released to production.     

Single-ended loop make-up identification-part I: a method of analyzing TDR measurements

Loop qualification consists of determining whether a loop can support digital subscriber line (DSL) services or not, and generally, the estimate of the transfer function is sufficient for such purposes. Loop qualification is one of the most important steps that service providers need to address in deploying DSL technology. In this paper, a solution to a more ambitious problem-single-ended automatic loop make-up identification, i.e., the determination of the length and the gauge of all loop sections (including bridged taps) via single-ended testing without human intervention-is proposed. Loop make-up identification will allow operators to more accurately qualify a loop for DSL service and to update and reorder telephone-company loop records, which can be accessed to support engineering, provisioning, and maintenance operations. Despite its potential importance, the possibility of achieving loop make-up identification via single-ended measurements has seldom been addressed in the literature. The use of time-domain reflectometry (TDR) measurements, which are analyzed by a novel step-by-step maximum-likelihood (ML) algorithm, is proposed here to achieve accurate loop make-up identification. In this paper, the proposed algorithm needs no a priori information, whereas in Part II of this study, a means to reduce the computation time of the identification algorithm will be provided, and the case where a statistical characterization of the loop may be available prior to testing will also be considered.     

Damage Tolerance Verification Concept of the ARIANE 5 Booster Case Welded Interface

In the course of an ARIANE 5 evolution program, the booster cases made of 48 CrMoNiV 4 10 high strength, low alloy steel will be modified such that 6 of the shear bolt connections will be replaced by EB‐welds as illustrated in Fig. 1. The introduction of welds has been chosen to achieve the following goals: • Mass reduction • Cost reduction • Increase of reliability • Simplification of thermal insulation application The concept of the damage tolerance verification which is in progress for justification of the improved booster cases is presented. By a very detailed local approach based on the characterization of the properties and the mechanical behaviour of the different zones of a weld seam, the overall damage tolerance of the weld shall be derived. The achieved prediction model has been verified by different component tests and will finally be qualified by a full scale qualification test.     

Novel Approach to Improve Electronics Reliability in the Next Generation of US Army Small Unmanned Ground Vehicles Under Complex Vibration Conditions

The functionality of next generation the US Army’s platforms, such as the Small Unmanned Ground Vehicles and Small Unmanned Arial Vehicles, is strongly dependent on the reliability of electronics-rich devices. Thus, the performance and accuracy of these systems will be dependent on the life-cycle of electronics. These electronic systems and the critical components in them experience extremely harsh environments such as shock and vibration. Therefore, it is imperative to identify the failure mechanisms of these components through experimental and virtual failure assessment. One of the key challenges in re-creating life-cycle vibration conditions during design and qualification testing in the lab is the re-creation of simultaneous multiaxial excitation that the product experiences in the field. Instead, the common practice is to use sequential single-axis excitation in different axes or uncontrolled multiaxial vibration on repetitive shock shakers. Consequently, the dominant failure modes in the field are sometimes very difficult to duplicate in a laboratory test. This paper presents the joint effort by the US Army Materiel Systems Analysis Activity (AMSAA) and the Center of Advanced Life Cycle Engineering (CALCE) at the University of Maryland to develop test methods and analytical models that better capture unforeseen design weaknesses prior to the qualification phase, by better replication of the life-cycle vibration conditions. One approach was to utilize a novel multi-degrees-of-freedom (M-DoF) electrodynamic shaker to ruggedize designs for fatigue damage due to multi-directional random vibration. The merits of vibration testing methods with six-DoF shaker and cost saving associated with such an approach will be addressed in this paper. There is a potential for M-DoF to detect critical design vulnerabilities earlier in the development cycle than has been traditionally possible with existing shaker technologies; and therefore to produce more cost effective, reliable and safe systems for the warfighters.     

Human-autonomy teaming interface design considerations for multi-unmanned vehicle control

ABSTRACT

Future applications are envisioned in which a single human operator manages multiple heterogeneous unmanned vehicles (UVs) by working together with an autonomy teammate that consists of several intelligent decision-aiding agents/services. This article describes recent advancements in developing a new interface paradigm that will support human-autonomy teaming for air, ground, and surface (sea craft) UVs in defence of a military base. Several concise and integrated candidate control station interfaces are described by which the operator determines the role of autonomy in UV management using an adaptable automation control scheme. An extended play calling based control approach is used to support human-autonomy communication and teaming in managing how UV assets respond to potential threats (e.g. asset allocation, routing, and execution details). The design process for the interfaces is also described including: analysis of a base defence scenario used to guide this effort, consideration of ecological interface design constructs, and generation of UV and task-related pictorial symbology.     

Validation of solid dosage forms the FDA view

In May 1987 the United States Food and Drug Administration published the final version of a guideline for process validation for pharmaceutical manufacturing. The document incorporated the comments from the pharmaceutical industry gathered after the publication of three draft versions in 1983, 1984 and 1986.

The presentation will cover the current definition of process validation as well as terms such as “worse case” and “installation qualification”.

The stages of process validation will be discussed including the written plan (protocol): records to be maintained; suitability of raw materials; equipment performance qualification; the number of runs required; and acceptance criteria.

Specifics for solid dosage forms will be presented along with details on batch record in instructions and establishment of acceptable range limits.

Circumstances and requirements for revalidation will be discussed as well as the validation of current finished dosage forms by retrospective validation.     

Reliability qualification of semiconductor devices based on physics‐of‐failure and risk and opportunity assessment

Qualification frequently is a time‐critical activity at the end of a development project. As time‐to‐market is a competitive issue, the most efficient qualification efforts are of interest. A concept is outlined, which proactively integrates qualification into the development process and provides a systematic procedure as a support tool to development and gives early focus on required activities. It converts requirements for a product into measures of development and qualification in combination with a risk and opportunity assessment step and accompanies the development process as a guiding and recording tool for advanced quality planning and confirmation. The collected data enlarge the knowledge database for DFR/BIR (designing for reliability/building‐in reliability) to be used for future projects. The procedure challenges and promotes teamwork of all the disciplines involved. Based on the physics‐of‐failure concept the reliability qualification methodology is re‐arranged with regard to the relationships between design, technology, manufacturing and the different product life phases at use conditions. It makes use of the physics‐of‐failure concept by considering the potential individual failure mechanisms and relates most of the reliability aspects to the technology rather than to the individual product design. Evaluation of complex products using common reliability models and the definition of sample sizes with respect to systematic inherent product properties and fractions of defects are discussed. Copyright © 2002 John Wiley & Sons, Ltd.     

Improving the Reliability in the Next Generation of US Army Platforms through Physics of Failure Analysis

Published studies and audits have documented that a significant number of U.S. Army systems are failing to demonstrate established reliability requirements. In order to address this issue, the Army developed a new reliability policy in December 2007 which encourages use of cost-effective reliability best practices. The intent of this policy is to improve reliability of Army systems and material, which in turn will have a significant positive impact on mission effectiveness, logistics effectiveness and life-cycle costs. Under this policy, the Army strongly encourages the use of Physics of Failure (PoF) analysis on mechanical and electronics systems. At the US Army Materiel Systems Analysis Activity, PoF analyses are conducted to support contractors, program managers and engineers on systems in all stages of acquisition from design, to test and evaluation (T&E) and fielded systems. This article discusses using the PoF approach to improve reliability of military products. PoF is a science-based approach to reliability that uses modeling and simulation to eliminate failures early in the design process by addressing root-cause failure mechanisms in a computer-aided engineering environment. The PoF approach involves modeling the root causes of failure such as fatigue, fracture, wear, and corrosion. Computer-aided design tools have been developed to address various loads, stresses, failure mechanisms, and failure sites. This paper focuses on understanding the cause and effect of physical processes and mechanisms that cause degradation and failure of materials and components. A reliability assessment case study of circuit cards consisting of dense circuitry is discussed. System level dynamics models, component finite element models and fatigue-life models were used to reveal the underlying physics of the hardware in its mission environment. Outputs of these analyses included forces acting on the system, displacements of components, accelerations, stress levels, weak points in the design and probable component life. This information may be used during the design process to make design changes early in the acquisition process when changes are easier to make and are much more cost effective. Design decisions and corrective actions made early in the acquisition phase leads to improved efficiency and effectiveness of the T&E process. The intent is to make fixes prior to T&E which will reduce test time and cost, allow more information to be obtained from test and improve test focus. PoF analyses may be conducted for failures occurring during test to better understand the underlying physics of the problem and identify the root cause of failures which may lead to better fixes for problems discovered, reduced test-fix-test iterations and reduced decision risk. The same analyses and benefits mentioned above may be applied to systems which are exhibiting failures in the field.     

A case study on the benefits of combining reliability stress tests

This paper discusses two distinct benefits associated with product reliability qualifications by combining individual reliability stress tests into a single test. First, a combined test will make better use of test equipment, personnel and product samples required for the qualification, implying a cost benefit. Secondly, a combined test allows interaction between the stress sources to occur on all failure causes. These benefits were realized as a result of a power supply application. Each individual test was designed to address specific causes which are assumed to be totally independent of other failures. A combined test can verify or deny independence and therefore provide a stronger practical test. Hence, this paper will demonstrate that a combined reliability test will provide more efficient testing with solid engineering product performance coverage. In addition, an approach is proposed for combining tests which fixes the acceleration rates between stress tests as the same ratio as under the nominal operating product environmental conditions.     

Workforce planning in the printing industry

Effective use of the workforce is often the crucial factor in a company's long-term success over its competitors, especially in technology driven and highly competitive industries such as the one considered in this article. While employee scheduling and rostering has been the topic of extensive research over the past decades, usually it is assumed that the size of the workforce is either given or can be obtained without difficulty. In this research we provide an integer programming model for long-term staffing decisions. The model is based on qualification profiles, the number of which grows exponentially in terms of the number of processes considered. We present empirical results for a company from the printing industry which highlight the potential of our approach. In particular, it will be shown that applying the model lowers the total cost of the workforce by 26–39%.     

A multi-objective military system of systems architecting problem with inflexible and flexible systems: formulation and solution methods

System of systems (SoS) architecting is the process of bringing together and connecting a set of systems so that the collection of the systems, i.e., the SoS is equipped with a set of required capabilities. A system is defined as inflexible in case it contributes to the SoS with all of the capabilities it can provide. On the other hand, a flexible system can collaborate with the SoS architect in the capabilities it will provide. In this study, we formulate and analyze a SoS architecting problem representing a military mission planning problem with inflexible and flexible systems as a multi-objective mixed-integer-linear optimization model. We discuss applications of an exact and an evolutionary method for generating and approximating the Pareto front of this model, respectively. Furthermore, we propose a decomposition approach, which decomposes the problem into smaller sub-problems by adding equality constraints, to improve both the exact and the evolutionary methods. Results from a set of numerical studies suggest that the proposed decomposition approach reduces the computational time for generating the exact Pareto front as well as it reduces the computational time for approximating the Pareto front while not resulting in a worse approximated Pareto front. The proposed decomposition approach can be easily used for different problems with different exact and heuristic methods and thus is a promising tool to improve the computational time of solving multi-objective combinatorial problems. Furthermore, a sample scenario is presented to illustrate the effects of system flexibility.     

Estimating Military Aircraft Cost Using Least Squares Support Vector Machines

A multi-layer adaptive optimizing parameters algorithm is developed for improving least squares support vector machines (LS-SVM), and a military aircraft life-cycle-cost (LCC) intelligent estimation model is proposed based on the improved LS-SVM. The intelligent cost estimation process is divided into three steps in the model. In the first step, a cost-drive-factor needs to be selected, which is significant for cost estimation. In the second step, military aircraft training samples within costs and cost-drive-factor set are obtained by the LS-SVM. Then the model can be used for new type aircraft cost estimation. Chinese military aircraft costs are estimated in the paper. The results show that the estimuted costs by the new model are closer to the true costs than that of the traditionally used methods.     

面向客户的产品规模定制设计及其应用

讨论产品设计过程中的基本模块，并提出规模定制设计的概念。面向客户的产品设计的核心是开发面向规模定制的产品族结构，实现与统一的产品开发和送货机制的后期集成。介绍了产品族结构的特点，以及明确产品族结构的步骤。同时给出了一个规模定制设计的研究实例。