CALCE Releases Web-based Handbook for Accelerated Testing
We are pleased to announce that the CALCE web-based Physics-of-Failure (PoF) guidelines for accelerated product qualification and quality assurance will be available to members by October 1, 1998. The web-based tools and guidelines facilitate integrating PoF approaches into the product qualification and quality assurance processes. This version of the PoF Guidelines includes detailed guidelines, test methodologies, and interactive case studies that allow a practicing engineer to efficiently plan and implement an accelerated test program. The information is presented in an interactive web-based HTML format that exploits its context sensitive searches, dynamic anchoring, and linking capability to online software tools. The web-based tool is structured as interlinked documents, illustrative case studies and interactive online failure models to facilitate a step-by-step walk through the entire PoF approach. The features of the web-based guidelines include:
This handbook is a dynamic, leading-edge tool whose content and features will continue to grow. For future plans, please consult the Assemblies Roadmap on the CALCE web site.
Parts Selection and Management Progress
Changes in electronic technologies and market dynamics have made traditional electronic parts selection and management practices inadequate. The CALCE Consortium is developing a parts selection and management process guidebook aimed at increasing company profitability in a manor that is consistent with the present environment. The book should be used as a guide in the development of company infrastructure and in the execution of daily business operations related to parts selection and management.
The CALCE Parts Selection and Management guidebook is progressing on schedule. The completion of five supporting projects (legal implications of part use beyond temperature specifications, part quality and integrity assessment, performance derating as an alternative to uprating, technology specific protocols of uprating, and part life cycle mismatch assessment) this October moves the guidebook into its final stages. The remaining three projects (application specific reliability assessment, assembly requirements and constraints assessment, and life cycle economics assessment), are being proposed as 1999 projects; the results of the remaining projects will be used to complete the guidebook, and allow its availability in October, 1999.
To compliment the project results, a Parts Selection and Management Workshop Series was held at the University from June 16 through June 18, 1998. Workshop findings have been used to assess, update, and improve the Consortium's Electronic Parts Selection and Management Guidebook.
CALCE Consortium member feedback has been significant in the development of the Consortium's guidebook. Nortel, for example, has invited CALCE to conduct a benchmarking study of their parts selection and management processes, with respect to part quality and integrity assessment and part reliability assessment. The results of the August study will be used both to offer Nortel process improvement recommendations, and to enhance the Consortium's guidebook contents. In addition to input from Nortel, CALCE continues to receive feedback from its members, including Aerospatiale, AlliedSignal, British Aerospace, Honeywell, Lucas Aerospace, and Wyler on the contents of the Consortium's draft document.
The remaining workshop proceedings are available to CALCE members at a cost of $150 per book. This cost covers printing and shipping fees. Please contact CALCE EPSC at (301) 405-5323 for more information about the workshops.
CALCE Educational Initiative Wins National Award
The CALCE Electronics Products and Systems (EPS) educational program is entering its sixth successful year. It leverages the results of $7M spent over the past five years on revamping the University of Maryland's engineering programs. So far 65 MS and 21 Ph.D. students have graduated from this curriculum and are occupying key technical and leadership positions in the industry. The program offers a unique series of dedicated courses, multi-media materials, expert guest lecture series, and industry internships, supported by world class laboratory and computational facilities, and a dedicated textbook series.
At the Electronics Components & Technology Conference held in Seattle in June 1998 a panel of judges awarded $30,000 for one year to CALCE EPSC and two other universities to develop internet based distance learning materials on thermal design of electronic systems. This award, sponsored jointly by IEEE, National Science Foundation, and the Packaging Research Center at Georgia Tech. was based on an article titled," A National Course on Thermal Design of Electronic Products: Recent Experiences and a Proposal", by Dr. Yogendra Joshi from CALCE EPSC, Dr. Avram Bar-Cohen from the University of Minnesota, and Dr. Sushil Bhavnani from Auburn University.
Under the auspices of the award, the team will create twelve hours of instructional modules, consisting of archival quality videos/CD-ROMs and internet-based high quality interactive multi-media materials to provide a comprehensive treatment of thermal design of electronic products. These will be self-contained to allow their incorporation in a "just-in-time" manner within a semester (or quarter) long national course or form an intensive two day short course. Another important use of these modules would be inclusion in undergraduate Heat Transfer and/or Fluid Mechanics courses, where they could provide the "thermal application" focus. They could also be used in a self-paced tutorial format for students in the 4th year Design Project course, who might need to better understand these issues. The Internet based modules will be accessible through a home page.
Unique features of this effort include:
For more information on this initiative, or on the CALCE Electronic Products and Systems (EPS) educational program, please contact the CALCE Center at (301) 405-5323.
Asian Up-Date Webpages
The "Asian Up-Date" is a service, which provides information on the Asian electronics industry. It consists of reports and articles covering past, current and future developments, the economic and industrial impact, and research in the Asian electronics industry. The purpose of the service is to provide engineers and managers with information on the technologies, manufacturing procedures, and capabilities of Asian countries.
Reports:
Current Listed Articles:
IEEE Standard Reliability Program for the Development and Production of Electronic Systems and Equipment
In May 1992, the U.S. Army Material Systems Acquisition Activity (AMSAA) and the CALCE Electronic Packaging Research Center (EPRC), University of Maryland, briefed the Army Standardization Executive, Mr. Darold Griffen on the problems with military reliability program standards, and recommended that Mil Std 785 "Reliability Program for Systems and Equipment, Development and Production" be updated. Mr. Griffin proposed the development of a dual use, non government reliability program standard, in lieu of revising Mil Std 785.
AMSAA and CALCE began working with the IEEE Reliability Society to develop an IEEE Reliability Program Standard, and received Working Group formation approval in August 1992; the project started in late 1993. Industry, government and academia recommendations were obtained through a questionnaire in the April 1994 IEEE Reliability Society Newsletter and formed the document philosophy.
The Working Group interacted with standards organizations that focus on reliability, including the Electronic Industries Association, Society of Automotive Engineers, American Society for Quality Control and the Institute for Environmental Sciences. The Working Group also collaborated with the United Kingdom Ministry of Defence and other participants in the international reliability standards arena, to make the new reliability program standard an effective starting point for updating international standards.
IEEE P1332, Standard Reliability Program for the Development and Production of Electronic Systems and Equipment, was officially approved on June 30. The IEEE standard provides guidance to suppliers to plan a program that suits their design philosophy, the product concept, and the resources at their disposal, so that every activity adds value. The objective of the standard is to provide products that satisfy the customer.
The next step is to develop a guidance document for P1332, which will include specific reliability assessment procedures. The Dallas, Texas chapter of the IEEE has agreed to begin preliminary research into this development. Please contact the IEEE at http://www.ieee.org, to obtain a copy of the P1332 standard to obtain information about guidebook development.
Status of the IEEE Reliability Prediction Standard
The IEEE P1413 Draft Standard Methodology for Reliability Prediction and Assessment for Electronic Systems and Equipment details the principles and approach to the documented methodology for reliability prediction and assessment for electronic systems and equipment. The objective of the standard is to identify key required elements for an understandable, credible reliability prediction and to provide the users of the prediction sufficient information for the evaluation of the prediction methods and the effective use of the prediction results. Please contact the CALCE Center at (301) 405-5323 for more information.
CALCE and ISIS Initiate Collaboration
CALCE EPSC and Infrared Screening and Inspection Solutions (ISIS), Inc. are pleased to announce a multi-faceted collaborative venture. ISIS manufactures infra-red imaging based test equipment for circuit card assembly inspection. This equipment uses non-invasive testing to detect defects at all stages of manufacture: design, engineering, production and troubleshooting. An Indium Antimonide infra-red radiometer, combined with thermal noise reduction capability allow sensing operating temperature differences as small as 0.025° C. Defects that have been identified repeatably and accurately include missing parts, dewets/voids, substrate delaminations, tombstoned parts, and weak, misaligned and wrong components. As part of the collaboration ISIS, Inc. will become a CALCE member and will provide their state-of-the-art equipment to CALCE. CALCE will advance the infrared based inspection methodology by developing couplings between test results and reliability assessment models, as well as new flaw detection algorithms. The ISIS system will be part of the testing services offered by CALCE to member organizations. For more information, please contact Dr. Abhijit Dasgupta at dasgupta@eng.umd.edu.
A Tool for Virtual Risk Assessment of Microelectronic Components
CALCE is pioneering the development of application-specific risk assessment tools leveraging off the existing reliability assessment software programs, which have been tested and improved by industry. CADMP-II, which is focused on component-level reliability assessment, offers a modular, integrated set of software programs, providing a wide range of analysis capabilities to support design tradeoff analysis. CADMP-II uses a physics-of-failure approach to reliability, based on modeling the fundamental mechanical, thermomechanical, chemical and electrical processes by which electronic components fail. The dominant mechanisms are determined by using validated models to calculate the time-to-failure for each potential failure mechanism. Physics-of-failure provides an application-specific method of assessing the reliability of many new designs as well as nearly all-existing components and systems.
This type of analysis allows a designer to choose package geometries and materials that reduce the risk of failure before investing in costly prototypes. This makes reliability assessment a part of the design process rather than just a tool for predicting the useful life of an existing product, allowing designer to proactively "build-in" reliability.
-New Developments
PEBB (Power Electronic Building Block) refers to a packaging concept that replaces complex power electronics circuits with an array of modular, multi-function devices that are intelligent and programmable. Introduction of standardized power electronic components for power conversion and modulation have the potential to dramatically reduce the cost and size of the electronic power systems. For example, depending on the application, a PEBB might be software configured to act as an AC to DC rectifier, DC to AC inverter, motor controller, actuator, frequency changer or a circuit breaker.
CADMP-II is being enhanced to address the design challenges of these power systems. These enhancements include:
- Decision-Support System
With the complexity of electronic packages increasing and design cycle times decreasing, design of modern electronic packages requires a method for rapidly trading-off multiple conflicting objectives at an early stage of product design. One set of tradeoffs occurs when packages can fail by multiple mechanisms. CADMP-II is being modified to alleviate this challenge by assisting the designer in selecting the parameters that optimize tradeoffs to produce the maximum time-to-failure across all the failure mechanisms.
- New Failure Model for Die Attach Fatigue
Cost-effectively ensuring the reliability of state electronic systems requires the use of physics of failure techniques to assess the reliability at the earliest design stages. This requires development of physics-of-failure models, which are composed of stress analysis and damage models.
Die attach fatigue due to thermal mismatch between the die and substrate has been identified as a prominent failure mechanism in power modules. Since power modules operate at high temperatures and use metallurgical die attaches such as soft solders, one cannot use conventional analytical models which consider die attach material to be elastic in nature. CADMP-II has incorporated a semi-analytical axisymmetric model for die attach fatigue suitable for power modules. It takes into account the viscoplastic behavior of die attach and has been validated using finite element analysis.
CADMP-II is available through membership in the Electronic Component Alliance. The Alliance provides member institutions with an opportunity to set the direction for CADMP-II development. More information on CADMP-II is available at http://www.calce.umd.edu.
calcePWA Models in IcePack
CALCE EPSC and Fluent have a cooperative agreement to provide data communication between the calcePWA software and the Fluent's IcePack software. This development will make it possible to import a PWA design modeled in calcePWA into IcePack and import analysis results from IcePack in calcePWA. This will provide calcePWA users with a state-of-the-art CDF package and IcePack users with a physics-of-failure based analysis package.
This partnership will open avenues for collaborative research in strategies for multi-scale modeling, compact/reduced models, and turbulance modeling in electronic systems. The software intergration is expected to be completed within six months.