Directed Self-Assembly of Block Copolymer for Bit Patterned Media with Areal Density of 1.5 Teradot/Inch2 and Beyond
Figure 11
(a) Large-scale SEM image of imprint resist pattern at 1 Td/in2. The imprint process was conducted on a standard 2.5 inch disk with a pillar-tone dots-array template at a density of 1.0 Td/in2 ( = 27.0 nm). The insets are a magnified SEM and AFM images from the data zone. (b) AFM image of imprinted servo features in the servo zone. (c) Cross-sectional AFM measurement showing that the imprint thickness is about 30 nm (shown by red arrows). The AFM tip cannot reach the bottom of the individual resist hole due to the small hole diameter (shown by green arrows).
