FabTime Cycle Time Management Newsletter Abstracts

FabTime Cycle Time Management Newsletter Abstracts - Volume 20 (5 issues - in progress)


The Impact of Tool Qualification on Cycle Time (Issue 20.05)

Welcome to Volume 20, Number 5 of the FabTime Cycle Time Management Newsletter. In this issue we have an announcement about the upcoming meeting of the Fab Owners Alliance and another about connecting with FabTime on LinkedIn. Our FabTime software tip of the month is about how FabTime calculates standby-WIP-waiting time, and why that is useful information.

We are trying something new with the subscriber discussion forum this month. We are seeking feedback in advance of the planned main article for the next issue of the newsletter: dispatch compliance. Any responses will thus be included in the same issue, and easier to refer to in the future. We also have a question from a subscriber about cycle time benchmarking. We would welcome responses from readers on that topic also.

In our main article for this issue, we discuss the impact of tool qualification on cycle time. While the impact of one-of-a-kind tools on fab cycle time is well known, the price of tool qualifications that lead to single-path operations is more significant than is sometimes realized. We illustrate this via FabTime’s Operating Curve Spreadsheet tool, which we are making available to newsletter subscribers for the first time. We hope you find the spreadsheet, and the discussion, useful.



How the Space Program Launched the Semiconductor Industry (Issue 20.04)

Welcome to Volume 20, Number 4 of the FabTime Cycle Time Management Newsletter. We hope you’re all having a great summer. We have no community announcements in this issue, but we have shared links to a couple of recent news stories that we thought would be of interest to our subscriber community. Our software tip of the month is about viewing the distribution of WIP across the line, with additional detail about the breakdown of that WIP.

We have two extensive and thoughtful subscriber responses to the main topic of the previous issue: the metric WIP Hours (hours of WIP in queue per tool). As these responses have made the subscriber discussion both lengthy and technical, we have chosen to include a brief main article. Inspired by the recent burst of news about the 50th anniversary of the moon landing, we share some commentary about the impact of the US space program on the semiconductor industry. We welcome your feedback.



Defining a Metric for WIP Hours (Issue 20.03)

Welcome to Volume 20, Number 3 of the FabTime Cycle Time Management Newsletter. In this issue we have an announcement about availability of new papers from the Winter Simulation Conference. Our software tip of the month is about saving data table configurations. We have no subscriber discussion this month, but we are seeking feedback about a metric defined in our main article: WIP hours. WIP hours is a metric used to compute the hours of WIP waiting at each tool, normalized by the number of tools that are qualified to run each wafer. We believe the WIP hours could be useful in identifying short-term bottlenecks and tool groups that could particularly benefit from additional cross-qualification. As always, we welcome your feedback.



A Metric for Green-to-Green (G2G) Analysis (Issue 20.02)

Welcome to Volume 20, Number 2 of the FabTime Cycle Time Management Newsletter. In this issue we have a call for papers for an upcoming conference. Our software tip of the month is about using our new interface for renaming, copying, and linking to home page tabs. We also have an extensive subscriber submission about capacity planning, on-time delivery, and dispatching.

In our main article, we discuss the metric Green-to-Green (G2G) time, which we are in the process of implementing in our software. This metric captures each instance of downtime, scheduled and unscheduled, from when a tool first goes down until it comes back up, even if there are multiple switches between downtime sub-states in between. We believe that this metric will be helpful to fabs in understanding and reducing downtime-related variability.



Cycle Time Metrics for Make to Stock vs. Make to Order (Issue 20.01)

Welcome to Volume 20, Number 1 of the FabTime Cycle Time Management Newsletter. It’s hard to believe that this is the 20th year of publication for this newsletter. Many thanks to all who have joined us along the way. We welcome your feedback on topics that we should cover in the coming year.

We hope that everyone’s 2019 is off to a great start. This issue’s software tip is about enabling and using FabTime’s Javascript charting engine. In our subscriber discussion forum, we seek your input regarding a new metric that we are implementing, Green to Green time. In our main article, we discuss metrics for make to stock vs. make to order production. Specifically, we question the use of the On-Time Delivery (OTD) metric for lots that are make to stock, and suggest other approaches.