Angus McCarter, Thomas Gilmore, Anshu Verma, Impedans Ltd., Dublin, Ireland
In the rapidly evolving field of semiconductor manufacturing, the optimization of plasma-assisted deposition and etching processes is critical for achieving high-quality results and enhancing production efficiency. This study explores advanced diagnostic techniques for real-time monitoring and optimization, focusing on Retarding Field Energy Analyzers (RFEAs) for ions and Voltage-Current (VI) probes from Impedans Ltd. Positioned at the substrate, the Semion RFEAs provide invaluable insights into the ion dynamics within plasma systems, enabling precise characterization of plasma surface interactions. By capturing spatial and temporal variations in the ion energy distribution functions and ion flux of positive and negative ions, RFEAs facilitate the identification of optimal process parameters, thereby improving uniformity and feature resolution. The Quantum is an advanced RFEA, that combines energy retarding grids with an integrated quartz crystal microbalance (QCM) allowing measurements of the ion energy and flux as well as the ion-neutral ratio and deposition rate.
Complementing RFEAs, Octiv VI probe offers a direct measurement of process parameters such as RF source power, bias power, pulsing frequency, and duty cycles. Careful selection of these parameters is essential for controlling and optimizing the feature size and their measurements enhances the understanding of plasma chemistry and its influence on etching and deposition rates, allowing for real-time adjustments to maintain desired process conditions.
This talk will highlight the applications of these RFEAs and VI probes in various etching and deposition processes ranging from laboratory grade experiments to industrial tools. Topics will include measurement challenges, innovative solutions, and successful case studies, shedding light on the transformative potential of RFEA and VI technology in advancing plasma-assisted processes.