Electron Beam Recording with a Novel Differential Pumping Head Realizing More than 50 GB/Layer Capacity Disc

Abstract

We developed an electron beam recorder with a novel differential pumping head, which produces a local high-vacuum area for an electron beam by balancing nitrogen gas flow into and out of the head. Regarding recording speed, it was confirmed to be as high as 4.92 m/s while maintaining a 10-3 Pa vacuum condition. In order to achieve a high speed recording velocity, we introduced an electron gun with a low acceleration voltage (15 kV) and a chemically amplified resist to the mastering to make resist sensitivity very high. In addition, it takes only 2 min to exchange the Si substrate. As for the performance of the electron beam mastering, a bottom jitter value appropriate for mass production was obtained from a 25 GB/layer capacity disc. We also fabricated a 50 GB/layer capacity disc and confirmed the HF signal using a near-field optical pick up for the first time. Furthermore, we were able to fabricate a 100 GB/layer capacity disc using our electron beam recorder.