Performance assessment of virtual metrology in APC applications for the viability of sampling reductions

This paper presents a detail investigation on the performances of adopting virtual metrology in applications of advanced process controls for the purpose of sampling reductions to cut down manufacturing costs. The intended application of virtual metrology is to replace hardware measurements instead of as digital gatekeeper or alarm-trigger of invoking advanced process controls. Whereas many feasibility instances have been reported, assessments of virtual metrology actually replacing hardware measurements for advanced process controls are few. This study investigates the performance boundaries that virtual metrology can be applied to advanced process controls without sacrificing process qualities. The limits govern whether virtual metrology can deliver what it is expected and help to map out directions of investment efforts prior to actual implementations.