Bit-Error-Rate Evaluation of Super-Resolution Near-Field Structure Read-Only Memory Discs with Semiconductive Material InSb

Bit-error-rate (bER) evaluation using hardware (H/W) evaluation system is described for super-resolution near-field structure (super-RENS) read-only-memory (ROM) discs fabricated with a semiconductor material, In–Sb, as the super-resolution active layer. bER on the order of 10-5 below a criterion of 3.0×10-4 is obtained with the super-RENS ROM discs having random pattern data including a minimum pit length of 80 nm in partial response maximum likelihood of the (1,2,2,1) type. The disc tilt, focus offset, and read power offset margins based on bER of readout signals are measured for the super-RENS ROM discs and are almost acceptable for practical use. Significant improvement of read stability up to 40,000 cycles realized by introducing the ZrO2 interface layer is confirmed using the H/W evaluation system.