Development of an AVM System Implementation Framework

Automatic virtual metrology (AVM) is the highest-level of technology for VM applications from the perspective of automation. It enables the fast application of VM to all pieces of equipment in a factory. The existing VM-related literature mainly focuses on creating VM models for manufacturing processes using different algorithms or methods and illustrating the defect-detection capability or the VM conjecture accuracy. Only a few of them mentioned how to implement the AVM system, but with limited details. This paper aims to present the development of an AVM system implementation framework (AVMSIF) to fill this gap. The proposed AVMSIF, together with the developed server-creation approach and XML-based system-operational mechanisms, can allow the complex AVM system to be created in a systematic and easy manner. Also, by adopting plug-and-play interfaces and desired functional modules, the AVMSIF can be applied to different types of equipment in the factory-wide VM deployment. According to the proposed AVMSIF, an AVM system has been successfully created and deployed in our cooperative thin-film-transistor-liquid-crystal-display (TFT-LCD) factory to confirm the effectiveness of the proposed AVMSIF. The results of this paper may be a useful reference for high-tech industries, such as semiconductor and TFT-LCD industries, in the construction of their AVM systems.