FabTime Cycle Time Management Newsletter Abstracts

FabTime Cycle Time Management Newsletter Abstracts - Volume 23 (4 issues - in progress)

Cycle Time and Holds Revisited (Issue 23.04)

Welcome to Volume 23, Number 4 of the FabTime Cycle Time Management Newsletter. It’s been a busy summer both within FabTime and around the industry. We are pleased to announce three new FabTime employees (one already with us and the other two starting soon). We also share several industry news tidbits from Jennifer’s LinkedIn, including the fact that wafer fab investments are headed to a record high this year. As suppliers to wafer fabs, we are grateful to see this capital expenditure. As long-time observers of the industry, we remain a bit nervous about potential capacity over-expansion. But we are overall hopeful!

We have no subscriber discussion in this issue. Perhaps all our readers were on vacation when the last issue came out.

In our main article this month we return to a topic last addressed here more than 15 years ago: the cycle time impact of holds. We discuss several ways that holds increase cycle time and share some associated management challenges arising from holds. We close with several recommendations for minimizing the impact of holds. In this month’s software tip, we focus on how to remove holds from the list of inactive lots, while keeping them visible using other charts. As always, we welcome your feedback.

Delivery Performance in Overloaded Wafer Fabs (Issue 23.03)

Welcome to Volume 23, Number 3 of the FabTime Cycle Time Management Newsletter. In this issue we have an announcement about a workshop we are holding for our software customers, as well as several articles from Jennifer’s LinkedIn about the chip shortage and the high-tech labor shortage. Our FabTime tip of the month is about using fiscal calendars when configuring FabTime charts.

Our subscriber discussion forum is brimming with questions and responses on topics from queue time limits to WIP linearity to capacity planning to operator productivity. We also have a response to the previous issue on managing cycle time while ramping starts. Our main article this month was inspired by a discussion with Hani Ofeck about meeting delivery performance targets in overloaded fabs. We welcome your feedback on that, as well as on the other subscriber discussion topics.

Managing Fab Cycle Time while Ramping Starts (Issue 23.02)

Welcome to Volume 23, Number 2 of the FabTime Cycle Time Management Newsletter. In this relatively brief issue, we have some highlights from Jennifer’s LinkedIn posts, a FabTime software tip of the month about using our new on-chart drill-down capability, and subscriber discussion about defining the components of cycle time and measuring fab linearity.

Our main article this month was inspired by a new subscriber to the newsletter. We always ask people who fill out subscription requests on our website “What is the most urgent cycle time issue occurring in your fab?” This subscriber wrote: “Ramping up starts and maintaining cycle time.” We realized that although we’ve written in the past about what to do to during an industry downturn, we had never written an article about what to do to protect cycle time during a strong upturn. We decided to remedy that omission. We share tips for squeezing additional capacity out of an existing tool set, deciding where to add capacity, and spending money in other areas beyond tools, all with an eye to keeping cycle times under control. We welcome your feedback, as always.

Using Operating Curves in Real Fabs (Issue 23.01)

Welcome to Volume 23, Number 1 of the FabTime Cycle Time Management Newsletter. We hope that the new year is treating you all well. In this issue we have a question assessing potential interest in a multi-company session of our cycle time management course, an announcement about the FOA Collaborative Forum (in person as of this writing), and some highlights from Jennifer’s LinkedIn. We have a FabTime software tip about the use of our new search bar. We have subscriber discussion about various topics, including a recommendation for a new blog on Factory Physics that we believe subscribers to this newsletter will enjoy.

We’ve talked many times in this newsletter about using queueing model-based operating curves to illustrate the impact of various factors on wafer fab cycle time. In our main article this month, we discuss the idea of populating these operating curves with data from real fabs. Reasons to do this include estimating the impact on cycle time from changes in utilization or other parameters and identifying places in the fab where the cycle time is worse than might be expected given the known characteristics of a tool group. We discuss techniques and pitfalls of collecting data for this effort. We show a detailed example from our demonstration server and then highlight possible uses of the operating curves. As always, we welcome your feedback.