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arXiv · 2608.14678

Information-Theoretic Causal Modelling of Semiconductor Process Dynamics

Daniel Sørensen·Giorgio Melchiorre·Sudip Bandyopadhyay·Sandip Halder·Roel Wuyts·Bappaditya Dey
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Abstract

With the progress of the semiconductor industry toward increasingly complex compute devices and tighter process tolerances, advanced process control has become crucial. This work explores a novel framework to infer the underlying dynamics of semiconductor processes, directly from raw equipment log-file time-series data. By modelling the tool dynamics as a stochastic dynamical system comprising (a) a deterministic component and (b) a stochastic component, we estimate entropy transfer rates between variables through the Liang-Kleeman and Pires formalism. Preliminary results indicated that 7.5% of the inferred dependencies were known, 36.0% were plausible, 17.5% represented previously uncharacterised relationships, and 39.0% were inconsistent with established process knowledge. These findings demonstrate the framework's capability to uncover novel causal insights, while motivating further improvements to reduce inconsistent findings.

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Daniel Sørensen, Giorgio Melchiorre, Sudip Bandyopadhyay, Sandip Halder, Roel Wuyts, Bappaditya Dey. 2026-08-04. Information-Theoretic Causal Modelling of Semiconductor Process Dynamics. https://arxiv.org/abs/2608.14678

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