Using megasonic agitation to extend chemical cleaning for nanotechnology device production

Aqueous and solvent chemicals are widely used in the semiconductor industry and as the technology nodes shrink device makers are working to extend these cleaning fluids to the next technology node. Internal data shows megasonic agitation can enhance polymer removal without complete dissolution for both aqueous and solvent chemicals. Data has shown solvents and semi-aqueous solutions show better selectivity with advanced material stacks over aqueous solution. It has been established that megasonic energy can enhance particle removal from semiconductor devices during cleaning processes. However, applied megasonic energy can also damage sensitive semiconductor devices during cleaning, especially in aqueous solutions. Aqueous fluids appear to promote much more damage for the same applied megasonic power than do most solvents. We show that some solvents have a higher threshold for cavitation than deionized water mixes. Since device manufacturers are working to extend their current cleaning chemicals to the 65 and 45 nm pilot production and research nodes, we studied several ways to accomplish this goal for aqueous or solvent chemicals. Described here we apply a methods to predict the damage of nanostructures by various liquids using signal analysis to better understand the mechanical that promotes improved control of cleaning without damage.