As the major data storage provider so far, the hard disk drive (HDD) industry based on magnetic recording is facing a tremendous challenge from the areal density growth. Due to the well-known superparamagnetic effect,1 current magnetic recording technique, perpendicular recording, may not be able to carry HDD too far beyond an areal density of (1 T). Next-generation magnetic recording technologies, such as heat-assisted magnetic recording2 and bit-patterned media (BPM),3 are under intense research and development at industry laboratories now. BPM, consisting of physically isolated magnetic single domains, put forward very stringent lithography requirements on the pattern density of , the pattern uniformity of bit size sigma, and the pattern addressability of bit position sigma.4 All those are very difficult to be satisfied simultaneously even using state-of-the-art “top-down” lithography techniques such as 193-nm immersion lithography, extreme ultraviolet lithography, or electron-beam lithography. Directed self-assembly (DSA) using block copolymers (BCPs) provides a versatile approach for nanopatterning at unprecedented resolution or pattern density.5–9 The control of long-range order and addressability of BCP nanodomains has been solved by applying commensurate pre-patterns with either chemical10–12 or topographical13 contrast. In the consideration of DSA for BPM fabrication, a comprehensive collection of all pattern information on a BPM disk is definitely needed first. The patterns on a BPM disk can be divided into two categories. One is located at regions called data zones, which consists of globally densely packed dot arrays with long-range order. The other is located at regions called servo zones. The servo patterns provide address information of each track and every bit in the data zones for the recording head to locate during data reading and writing. For this purpose, alternative magnetic and nonmagnetic areas are designed in the servo zone. In our servo design, locally densely packed dot arrays with short-range order are pursued.