Fab cycle time improvement through inventory control : a wafer starts approach

Intel's Colorado Springs wafer fabrication facility, known internally as F23, has undertaken several initiatives to reduce cycle time including High Precision Maintenance (HPM), content reduction through the application of Manufacturing Excellence (mX), effective utilization of production equipment, and aggressive inventory control. Each of these efforts has contributed to the marked improvement F23 achieved throughout 2006. F23's cycle time efficiency, the ratio of raw process cycle time to actual fab cycle time, improved from 12% (worst amongst Intel facilities) to greater than 35% (best amongst Intel sites), and overall cycle time was reduced by more than 61% in 2006. Inventory control was found to have a major impact on factory cycle time and performance. F23 controls its factory work-in-process, WIP, inventory through the F23 Wafer Starts Protocol. F23 utilizes Little's Law (Cycle Time = Inventory / Output) to identify target WIP inventory levels required to achieve particular cycle time goals. The target inventory is then achieved by modulating wafer starts. To do this, the Wafer Starts Protocol monitors the inventory of the overall fab and the constraint operations and suggests the amount of wafers to start for each shift.

Department dc:contributor.department

Leaders for Manufacturing Program at MIT

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Ward, Matthew John

Advisor dc:contributor.advisor

• Stephen C. Graves and Deborah J. Nightingale.

• Sloan School of Management.
• Engineering Systems Division.
• Leaders for Manufacturing Program.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/39681

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39681