In this study, we investigated the limitations of optical reading of very fine pits using conventional optics, immersion lens optics and near-field optics. Using very fine pits < 100 nm in size formed by electron beam writing, a reflection-type depolarization scanning near-field optical microscope (SNOM) read very fine pits < 50nm in size. On the other hand, far-field optics read fine pits only > 160 nm in size using a lens with a numerical aperture (NA) of 0.95 (17 Gb/in2). In addition, an oil immersion lens optics with a NA of 1.4 read fine pits only 100 nm in size (45 Gb/in2). Advanced near-field optics is a promising tool for achieving ultrahigh-density optical reading of trillion bits/in2.
|ジャーナル||Japanese Journal of Applied Physics, Part 2: Letters|
|出版ステータス||Published - 2002 8 1|
ASJC Scopus subject areas