By Leonid Rosenboim, MKS Instruments Inc.

Collection and analysis of physical measurements have become crucial components in advanced process control (APC) and e-diagnostics for semiconductor manufacturing. To further advance diagnostics capabilities, tool suppliers and device makers are increasing the number of sensors used in process chambers to improve manufacturing steps and ultimately achieve higher yields. This article discusses tradeoffs and interface considerations when using process-control sensors for data collection and analysis of measurements in IC fabrication lines.

Sensors that monitor various aspects of semiconductor processes are primarily used for controlling processes and maintaining critical process parameters within assigned tolerances. However, it also has become increasingly popular to use sensors to collect, store, and analyze data independently from process control. In these applications, various physical measurements often are collected from chamber sensors and stored for offline analysis, which aims to correlate a number of data sources to determine root causes of process failures or to predict preventive maintenance for equipment. Various instruments used to measure and control physical and chemical processes can serve data-collection applications, depending on the particulars of the process at hand. These typically include various gas-pressure sensors, temperature transducers, mass flow controllers, RF and DC power sources, and energy transmission instruments.