Sensor integration into plasma etch reactors of a developmental pilot line

During the course of the Microelectronics Manufacturing Science and Technology (MMST) program, a number of sensors have been integrated into various test‐bed plasma etch reactors with the goal of monitoring, diagnosing, and controlling these processes. These sensors include single wavelength and spectral ellipsometers for real‐time in situ etch rate and endpoint determination; a standard monochromator for etch rate and nonuniformity measurements; an eddy current sensor for incoming metal thickness control; a rf monitor for rf current and voltage diagnostics; and a scatterometry‐based critical dimension sensor for linewidth measurements. The full integration of these sensors turned out to be a complex and time‐consuming task including hardware, optical, software, material, and processing issues. Once integrated into the reactor, and the appropriate process modeling completed, these sensors enabled the monitoring, diagnosis, and model‐based control of these processes. Besides maintaining specific process ob...