DTM and BPM Pattering Considerations Using S-FIL: Double Side Imprinting and Imprint Mask Replication Processes through Pattern Transfer

David Lentz, Mike Miller, Gerard Schmid, Cynthia Brooks, Paul Hellebrekers, Scott Carden, Steve Johnson, Douglas J. Resnick, S.V. Sreenivasan and Dwayne LaBrake

Abstract:

The Step and Flash Imprint Lithography (S-FIL) process uses drop dispensing of UV curable liquids for high resolution patterning. Patterned media is particularly challenging because of the aggressive pitch size necessary to achieve storage densities required for media manufacturing beyond current perpendicular recording. In this paper, the fabrication of master imprint masks, the replication of these to create working imprint masks and data from patterning of disks by double side imprint techniques is described.

For successful manufacturing of DTM and BPM patterned media low cost imprint masks and double side imprinting are required. Master imprint masks are fabricated using rotary stage high resolution electron beams and resists to define the bit pattern. Subtractive etching of a Cr hard mask followed by a fused silica etch is used to form template patterns. To realize low cost the master imprint mask is replicated by S-FIL imprinting onto a blank fused silica substrate using an automated imprint tool configured to handle 6” substrates. After pattern transfer the working imprint mask having the proper tone for disk patterning is used in a high speed (>180 dph) double side imprint tool to apply the resist mask used for disk patterning. This paper will focus on the data from the imprint equipment, process flow and lithographic performance through pattern transfer developed for imprint mask replication and double side imprint patterning. Special attention will be given imprint performance including throughput and alignment performance. Manufacturing process flows and results obtained patterning 100 nm pitch DTM and 50 nm pitch BPM patterns will be presented.