Enhancing lithography precision: characterizing resist profiles in semiconductor manufacturing with rapid probe microscopy

The lithography process in semiconductor manufacturing demands precise control over focus and exposure parameters to achieve optimal lithographic outcome for the structures being printed. It has become increasingly important to fully characterize the resist (3 dimensional) profile after development, since it is known that the optimum focus level and exposure dose may differ according to the parameter in question. For example, the optimal settings for CD and for minimizing stochastics effects may not be the same. In this study, we demonstrate the use of Rapid Probe Microscopy (RPM) to evaluate a Focus-Exposure-Matrix (FEM) in EUV lithography. RPM offers deep sub nanometre resolution and true 3-dimensional measurement, enabling the characterisation of variations critical to the lithographic process.