Conference Paper

Multilevel statistical process Control of asynchronous multi-stream processes in semiconductor manufacturing

Univ. of Pavia, Pavia, Italy
DOI: 10.1109/COASE.2010.5584508 Conference: IEEE Conference on Automation Science and Engineering, CASE 2010, Toronto, ON, Canada, 21-24 August, 2010
Source: DBLP


In semiconductor manufacturing, the purpose of chamber matching is the alignment of process and yield results of distinct chambers performing in parallel the same process step on different silicon wafers. In this paper, multi-level linear models and statistical process control techniques are jointly employed to define control charts for monitoring chamber matching accuracy and preemptively report chamber misalignments. Specifically, multilevel versions of the classic T2 Control Chart, MEWMA Control Chart and Self-Starting Control Chart are defined and tested against experimental and simulated data.

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