Optical critical dimension measurements for patterned media with 10's nm feature size

Patterned media is expected to be implemented in future generations of hard disk drives to provide data storage at densities exceeding 1012 bits/in2 and beyond. The implementation of patterned media, which would involve developing processing methods to offer high resolution (small bits), regular patterns, and high density, has posed a number of metrology challenges. Optical Critical Dimension (OCD) is the leading candidate to overcome the metrology challenges for patterned media. This paper presents the successful OCD measurements on the critical dimensions, sidewall-angles, and detailed sidewall shape of gratings of quartz template and imprint disk with pitch as small as 57nm.