FabTime Cycle Time Management Newsletter Abstracts

FabTime Cycle Time Management Newsletter Abstracts - Volume 17 (6 issues)

Thinking Critically About Data (Issue 17.06)

In this issue we have a community announcement about the 25th anniversary of Wright Williams and Kelly. Our software tip of the month is about using the relatively new stacked starts and shipments charts. We have no subscriber discussion during this busy time of year.

We have a new type of main article this month. We share a detailed recap of a new nonfiction title including our own commentary on how the topic relates to the semiconductor industry. The book highlighted is “A Field Guide to Lies” by Daniel Levitin, about applying critical thinking to information presented in the form of data, words, and pictures. We also include a recent example of a statistic miscalculated by Facebook, as well as discussion, where applicable, of how Levitin’s comments apply to FabTime and other reporting products. We would be especially interested to know whether you find this type of article useful.

Computational Issues in Reporting "Average WIP" (Issue 17.05)

In this issue we have one announcement, about FabTime team members running the SLO Ultra. Our software tip of the month is about copying chart images to other applications (a modified tip that reflects changes due to our custom JavaScript charting engine). We have a subscriber discussion question regarding the choice between one automatically loaded tool and two manually loaded tools. Long-time readers will be able to guess FabTime’s thoughts on that question.

In our main article this month we look at computational issues in reporting and calculating WIP-related metrics, particularly WIP turns. If there is one thing that we’ve learned in our years of working with fab data, it’s that even things that seem straightforward can become complex, when you get down into the nitty-gritty details. Computing average WIP is no exception. As always, we welcome your feedback.

Managing High-Mix Low-Volume Wafer Fabs (Issue 17.04)

In this issue we have a brief announcement about two new FabTime interns. Our software user tip of the month describes two ways to move a chart to a different home page tab. We have no subscriber discussion this month, but we do have a main article that we hope will generate discussion for future issues.

This main article, co-written with Mike Hillis from Cypress Semiconductor, is about the rise of and challenges in managing high-mix, low-volume fabs. The increased market segmentation of high-tech products is likely to drive ever-increasing levels of product mix, with lower volumes of many individual products. This combination of high mix and low volumes exacerbates many of the management challenges already present in wafer fabs. It is in all of our interest to come up with better solutions for managing such facilities. We hope that this article launches a productive discussion.

Why Fabs Need Multiple Metrics (Issue 17.03)

In this issue we have an announcement about the FabTime Virtual User Group. Our software tip of the month is about using effective dates to ramp goals over time. We have one subscriber discussion topic, concerning the benefits of foundries vs. in-house fab manufacturing.

In our main topic this month we discuss the pressure that arises sometimes in fabs to focus on a single metric, and the reasons that this isn’t a good idea in the complex environment of a fab. We review a number of candidate super metrics, and conclude with a framework for using multiple metrics in an integrated fashion. As always, we welcome your feedback.

FabTime Short-Interval Scheduling (Issue 17.02)

In this issue we have calls for papers for two upcoming conferences, both of which include topics that may be of interest to the newsletter community. Our software tip of the month is about controlling the way that slice-by objects are filled in (when they have no WIP) on WIP and Moves Pareto charts. We have no subscriber discussion this month, though we do welcome your questions or feedback on fab manufacturing-related topics.

In our main article, we introduce the methodology included in FabTime’s new short-interval scheduling module. The scheduler attempts to solve certain issues inherent in traditional dispatch systems by looking forward to create a series of reservations for each tool. This better handles fab complexities like back-to-back time constraint regions and setup avoidance planning. We welcome your feedback.

A Hidden Source of Cycle Time in Wafer Fabs: Gas and Chemical Changes (Issue 17.01)

In this issue we have an announcement about a promotion for FabTime’s Teresa Fallwell, and about FabTime’s participation in next week’s FOA Collaborative Forum. Our software tip of the month is about sorting moves trend and pareto charts by delta from goal (to identify objects that are furthest from meeting their goals). In our subscriber discussion forum we have several responses to last issue's main article about cluster tool OEE, including a couple of minor corrections.

In our main article this month we share a guest article by John Taylor of TR Control Solutions. In this article, John outlines a sometimes hidden source of cycle time problems in wafer fabs: managing gases and chemicals. Expirations and stockouts of gases and chemicals can result in downtime and / or yield problems, both of which, as we well know, can contribute to wafer fab cycle time. TR Control Solutions offers a commercial product to help manage gas and chemical usage and expiration data. We imagine that many of you have your own solutions, and we welcome your feedback as we discuss this new-to-us fab performance management challenge.