Wavelength influence on the determination of subwavelength grating parameters by using optical scatterometry

As the semiconductor industry rapidly approaches the 3nm lithography node, on product overlay (OPO) requirements have become tighter and as a result, residuals magnitude requirements have become even more challenging. Metrology performance enhancements are required to meet these demands. Color Per Layer (CPL) is a unique imaging overlay...

Far-field sectioning for the retrieval of subwavelength grating parameters using coherent Fourier scatterometry

Optical inspection of periodic nanostructures is a major challenge in the semiconductor industry due to constantly decreasing critical dimensions. In this paper we combine coherent Fourier scatterometry (CFS) with a sectioning mask for subwavelength grating parameter determination. By selecting only the most sensitive regions of the scattered...