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The world's largest computer manufacturer is developing an Automated Logistics and Production System (ALPS).

Today's electronic assembly manufacturing operations can be complex combinations of process steps such as IR reflow, wave soldering, special soldering of connectors or sensitive components, cleaning, rework, etc. Such multiple exposures to elevated temperatures and/or oxidising environments (e.g., aqueous cleaning) can have a negative effect on the solderability of printed wiring board (PWB) surfaces. This in turn may limit the effectiveness of subsequent soldering operations, such as wave soldering following an IR reflow step. The purpose of this study is to assess the impact of individual assembly process steps on the solderability of PWB surfaces. The PWB surfaces are initially treated with protective coatings of benzotriazole (BTA). The process steps investigated include: IR reflow in air and in nitrogen; vapour phase reflow; aqueous cleaning; adhesive cure; and wave soldering as a function of solder temperature and flux type. Meniscograph wettability testing is used to measure relative solderability changes, and Auger electron spectroscopy (AES) is used to monitor surface chemical changes, particularly oxide formation. The overall result is a body of fundamental information providing insight into optimisations of process flows, equipment operating specifications, process temperatures and selection of flux types.

Reliability evaluations for new electronic components and assemblies regularly require extensive test cycles that are both time consuming and costly. Objectives of such test batteries are to identify failure mechanisms and the relationship between these mechanisms and product design or processing features. Optimisation of these critical factors or process steps results in optimised reliability. Statistically designed experiments can facilitate the optimisation process by minimising the amount of testing needed to identify factors affecting reliability, and by providing insight into how these factors can be specified to ensure optimum product design. Designed experimentation was utilised in this study to look at product design and process factors affecting the reliability of inner leads for tape automated bonding (TAB) components. Four factors are considered: outer lead compliancy; chip immobilisation; downset; and tape stiffness and rigidity. Experimental details and results are presented which assess the relative importance of these factors in determining ultimate inner lead reliability, and also provide guidance for final product design considerations.

Describes a dynamic approach to quality function deployment (QFD) that translates customer wants and needs into relevant product and process parameters. Using feedback loops, this new approach incorporates updated customer satisfaction data and dynamically links evolving requirements directly back into manufacturing and related processes. Updated customer requirements “peg” the key parameters in statistical process control charts. Introduces the concept, illustrates the mechanics of the approach, and describes how it benefited an IBM assembly plant.

A case study by IBM of machine vision implementation in the robotic assembly area of the Automated Logistic Production System used in manufacturing computers.

This paper describes the approach used by the authors to select the flux materials for a simple water‐soluble solder paste flux formulation, what those materials were, and how they interacted to give the correct properties. Consistency of formulation and performance are discussed with emphasis on the need for adequate process parameter control as with any formulation. With this water‐soluble paste formulation various circuit card designs were successfully built possessing 25‐mil pitch, and larger, components. The cards were cleaned in aqueous cleaners and passed IBM standard insulation resistance testing.

The magnitude of Texas A&M's revision of its collection policy is evident in the doubling of the student population to 36,000 over ten years and a 69 percent collection growth to 1.44 million volumes. The intensity of the change in demands on the collection, whether in titles purchased, variety of formats, or depth of subject representation, required a major effort on the part of collection development staff. Collection development staff surveyed the University's teaching as well as research arms involving the capabilities of all university librarians. The net result was an updated collection development policy, the development of a self‐teaching guide for future collection development undertaking, and an increased awareness on the part of the librarians about the university as well as on the part of the academic faculty about the university librarians' capabilities.

As plastic ball grid array (PBGA) components proliferate, card assembly questions arise about the robustness of the module to card attachment process. A designed experiment was performed to measure the sensitivity of card assembly yields to normal assembly process variation. Experimental variables include card thickness, ball pad size on the card ball grid array (BGA) site, module moisture exposure and ball planarity of a 225 I/O PBGA. Another set of PBGA test cards, assembled under optimum process conditions, was subjected to accelerated thermal cycle (ATO) testing. ATC testing also included a rework cell. Overall, the PBGA module attachment process demonstrated robustness. The initial attach and reworked modules proved to be reliable. This paper focuses on the details of the test conditions and the results.

During the first half of this year the Association has continued to expand its exhibition programme by increasing its presence at overseas shows. Two DTI sponsored joint venture groups have been formed, one to Nepcon West, the other to Nepcon Beijing. Anaheim saw the biggest UK group for over 10 years, with CEMA taking three separate blocks in different sectors of the show. There is no doubt from the reception we received that CEMA is now firmly established at Nepcon West. We enjoyed tremendous support from both the British Consulate and the British‐American Chamber of Commerce with their President making several visits to the CEMA booth.

Predictions can be fun to make, and the temptation must be overwhelming if you're an “expert” in a field as dynamic as personal computing. For that matter, market analysts are paid to make projections. Thus, the PC field doesn't lack for insights into the future. If you base your plans on those predictions and projections rather than your understanding and a touch of caution, you can be led seriously astray. As with most other projections for the marketplace, PC predictions range from superb to awful. Worse yet, some supposedly objective analysts become advocates—coloring their projections with their hopes. To wrap up this year‐long look back at a decade of personal computing, the author notes a few of the failed predictions and assertions that litter the computer press. Hindsight is always easier than foresight, and some of these predictions should have been correct. Meanwhile, it's worth noting a few general areas where projections have gone wrong.