Demonstration of “full disc” bit patterned media


Paulina A. Rincon Delgadillo; Roel Gronheid; Christopher J. Thode; Hengpeng Wu; Yi Cao; Mark Neisser; Mark Somervell; Kathleen Nafus; Paul F. Nealey

Thrust 1 research has led to the first “full disc” demonstration of magnetic bit patterned media. With the fine tuning of the process conditions, the process flow provided chemically patterned substrates with well-defined geometry and chemistry. PS-b-PMMA was self-assembled on a chemical pattern to obtain 4X feature multiplication and fabricate silicon masters with both radial and circumferential tracks. Using two sequential nanoimprinting steps, the radial and circumferential submaster line patterns were combined into a final quartz master template with rectangular bits on circular tracks.

   
Top-down SEM images of chemical patterns (LS = 100 nm) and corresponding assembled PS-b-PMMA on the chemical patterns, as a function of exposure dose and focus settings used to generate the chemical patterns. The PS-b-PMMA assembled on the chemical pattern with 4x density multiplication. Overview schematic of the fabrication of nanoimprint templates with rectangular patterns using directed assembly with block copolymers and double nanoimprint.