Improvement of Electron Beam Recorder for Mastering of Future Storage Media

An electron beam recorder for optical disk mastering was improved for future storage media. One improvement was related to a formatter to record constant angular velocity formats like servo patterns of hard disks. The formatter draws patterns with constant linear velocity by controlling the translation stage, the rotation stage, the beam blanker, and the high-speed deflector synchronously. The operation of the formatter was demonstrated by test drawing standard servo patterns that aligned in the radial direction and along the arc trajectory of a swing-arm actuator. Another improvement was a reduction in electron beam size. An electron beam column with a 50 kV acceleration voltage for optical disk mastering was improved by incorporating a new objective lens, the magnification of which was about 40% of the former lens. As a result, 58.5-nm pitch land-and-grooves were resolved with a linear velocity of 0.55 m/s. Furthermore a 100 kV electron beam column was developed to reduce the beam size to 10 nm or less. The width of fabricated grooves drawn by the column was about 12 nm.