Directed Self-Assembly of Block Copolymer for Bit Patterned Media with Areal Density of 1.5 Teradot/Inch2 and Beyond
Figure 12
(a) SEM image of a 1.5 Td/in2 ( = 22.3 nm) pillar-tone dots-array template in the data zone. (b) Cross-sectional SEM image of the template showing a vertical sidewall with etched pillar height of about 33 nm. (c) 8 nm thick 1.5 Td/in2 CoCrPt dots formed using a 16 nm thick carbon layer as hard mask and etched into magnetic layer by argon IBE process. (d) Magnetic loop with high coercivity kOe.
