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Advances in block copolymer directed assembly have highlighted the potential of block copolymer lithography to define patterned templates for magnetic recording bit patterned media (BPM). The naturally periodic features found in block copolymer films display superior size uniformity at ultrahigh densities, making them ideal lithographic masks to define the highly periodic data bits in the data sector of hard disk drives. In addition to the data bits, BPM architecture requires additional features to encode servo information. Because of the nature of the information stored in servo sectors, the geometry and shape of servo features differ from those in the data sectors, potentially compromising their compatibility with the features that can be naturally formed by block copolymers. The authors investigated the compatibility of a block copolymer directed assembly with the formation of complex chevron structures for sector header servo patterns within the framework of a BPM design that uses rectangular bits as the storage units. In order to ensure proper registration between the data tracks and the chevron patterns, the authors propose a design that employs lamellae-forming block copolymers assembled on chemical patterns with density multiplication into sets of lines that define both the data tracks and the servo features simultaneously. Due to the high free energy penalty associated with bending the lamellar domains, the block copolymer formed defective structures at the apex of the chevrons, as well as in the junction areas between chevrons and periodic horizontal lines. Adding stripes to the design of the chemical patterns near these complex areas prevented defects from propagating into the periodic line areas. In addition, the predictable defective structure offered flexibility for subsequent signal processing such as track identification and head position correction.