A Novel CP Approach for Scheduling an Automated Wet-Etch Station

JUAN MATIAS NOVAS; GABRIELA PATRICIA HENNING

Congreso; 21st European Symposium on Computer-Aided Process Engineering - ESCAPE 21; 2011

This paper presents a novel, efficient, and expressive Constraint Programming (CP) model to address the Automated Wet-Etch Station (AWS) scheduling problem. This CP model overcomes some of the shortcomings of previous approaches since it can explicitly take into account the time employed by any empty robot to move itself from the bath where it dropped a wafer lot to another bath where it is required to pick up a different lot. Such transfer time, which depends on the travel distance, needs to be considered to avoid overexposure of wafers in chemical baths. The formulation has been extensively evaluated in productivity maximization scenarios.