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JOHN CONWAY, Schneider Electric, Raleigh, NC, USA
JEFF. SEWARD, IBM Microelectronics, Burlington, VT, USA

ABSTRACT

This paper discusses the implementation challenges encountered when integrating smart sensors with manufacturing equipment to detect processing faults and improve yield. To overcome these problems, reliable and industry-hardened solutions must be deployed which are based on an open architecture. Certain sensor-based solutions must be able to perform control functions in real-time (measured in milliseconds) and if necessary intervene to halt the manufacturing process independently of the Manufacturing Execution System (MES) and Advanced Process Control (APC) system. Additionally, the use of commercial PCs on the factory floor must be limited. These requirements logically led to the selection of fully integrated Programmable Logic Controllers (PLC) to perform the real-time data collection and control functions. Fault-tolerant networking topologies for integrating sophisticated sensors are examined. The approach is centered upon the use of the SEMI Sensor Bus standard based on MODBUS TCP/IP Ethernet. This methodology leverages leadership in networking technology. The standard, and the integration advantages it offers, is explained along with examples of its use on critical process tools in the fab. Linked to this is the integration of the sensors within the APC framework, which is also discussed. The end result is a system which will speed the acquisition of critical process information by driving internet/intranet technologies down to the sensor level. What is achieved is great simplification of the deployment and support of smart sensor technologies on the factory floor.