Readout characteristics of light-scattering-mode super- resolution near-field structure (super-RENS) disks are described in detail. Readout intensities in reflected and transmitted signals are compared. Both signals showed mostly the same carrier-to-noise ratios (CNRs) using objective lenses with NA of 0.6. The formation mechanism of light scattering centers in the super-RENS disks ia also described in comparison with several different disks. As increasing oxygen ratio during the deposition of silver oxide (AgOx) layers, two different chemical reactions were identified. It was found that the super-RENS disks with oxygen-rich AgOx films have both characteristics of transparent and light- scattering apertures in one disk. Further study also revealed that the AgOx dynamic nonlinearity is not so high and less than 6% by the film itself; however, it is enhanced to 12% in super-RENS. It is supposed that the imaginary refractive index k of the films is less than 0.1; therefore, it is hard to heat itself to the decomposition temperature without a heat source (GeSbTe film) underneath. This result would be a hint to further increase CNRs in a light- scattering-mode super-RENS disks.
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