Design for Maintenance

The need to reduce equipment down time is becoming a key enabler to deliver increasing tool output for next generation equipment capabilities needed to maintain the productivity curve as discussed by ISMI (ismi.sematech.org /wafersize/docs/450mmBriefing.pdf and ISMI document #06114819B-ENG). There are many ways of improving equipment availability by reducing maintenance time and improving equipment "green to green" - the time required to get equipment back to running normally after a scheduled or unscheduled downtime. Today's capital equipment has some capabilities for integrated maintenance instructions but those instructions are frequently limited to manuals and software meant to be used off-line when the tool is not running. Predictable repairs and a consistent approach to maintenance can be achieved by enabling parallel maintenance, swapping components or entire modules, or by making significant improvements in the integration of the tool supervisor software and the factory maintenance expert database systems. Frequently the fab has a significant knowledge base of proper maintenance procedures and correct error recovery procedures, but such learning is hardly ever easily integrated into the supervisory architecture of the tool.