ISMI News
ISMI Reveals Cost-Saving Method for Correcting Process Variation in Fab Tools
Austin, TX (7 February 2007) — A money-saving methodology that allows fab managers to adjust an errant piece of equipment by matching it to the best-performing tool of its type has been developed by process engineers at International SEMATECH Manufacturing Initiative (ISMI).
ISMI’s Equipment Chamber Matching (ECM) Method combines the shared best practices of the consortium’s member companies into an 11-step process designed to rein in the “rogue tools” that often plague microchip manufacturing managers and drive down factory productivity.
In effect, ECM engineers identify differences between a “golden tool” and errant processing chambers in a production line. After doing so, the rogue chambers can be calibrated – much as a musician uses a tuning fork to adjust an instrument to the correct pitch.
“The beauty of the ECM Method is that it requires no capital investment to implement, so our ISMI members can achieve a high return with minimal outlay,” said Lorn Christal, project manager in ISMI’s Equipment Productivity Program. “We believe our members will be able to save millions of dollars per tool per year in cases where mismatched chamber issues can be identified and corrected.”
The ECM Method is modeled after Six Sigma practices, a system originally developed by Motorola to systematically improve processes by eliminating defects. “This method provides a fundamental approach for chamber matching,” said Masato Sadaoka, a Renesas assignee to ISMI. “It helps engineers engaged in daily improvement activities to enhance device yield and equipment utilization, with the goal of reducing process variation.”
The ECM Method resulted from a year-long study in which ISMI members contributed data on how their fabs identified and corrected chamber mismatching issues. While individual company methods varied, their common threads were drawn together into a unified problem-solving guide.
“The ECM Method distills the best practices of ISMI's member companies into a single, comprehensive approach,” said Neal Marmillion, IBM assignee and ISMI Equipment Productivity Program Manager. “By combining this method with data analysis applications available from third parties, ISMI members will be able to further accelerate their chamber matching solutions.”
ISMI engineers provided members with an initial version of the ECM Method in May 2006, then validated the method by utilizing test cases in members’ fabs later in the year. The results, according to Christal, were “overwhelming” – member companies identified savings from the validations of $500,000 to more than $5 million. “The ECM Method is one solution that equipment engineers should use to effectively and efficiently engage mismatched chamber issues.” said Dr. Sang Yeob Cha, a Samsung assignee to ISMI. “The method should be learned by all engineers.”
Dr. Diane K. Michelson, Member of Technical Staff at ISMI, said the method also allows companies to save time and money by enabling systematic design of experiments for process improvements. “The ECM Method ensures efficient use of engineering and equipment resources by providing a systematic flow for determining the current matching status of equipment chambers, as well as how to match them,” she noted.
During 2007, ISMI will follow up its methodology work by benchmarking and demonstrating ECM-related applications from selected suppliers. These demonstrations are expected to show how specific applications allow for efficient and accurate analysis of equipment data necessary to implement the ECM Method successfully.