Surface plasma ultra-diffraction photoetching method based on tip-insulator-metal structure

Abstract

The invention provides a surface plasma ultra-diffraction photoetching method based on a tip-insulator-metal (TIM) structure. The surface plasma ultra-diffraction photoetching method is characterized in that a TIM resonant cavity structure is formed by tip-insulator-metal, a light is emitted in a substrate containing the resonant cavity in a normal incidence manner, a probe tip of a probe stimulates local surface plasmas (LSP), the waves of the stimulated local surface plasmas are reflected and coupled by a metal reflection layer in a downward attenuation propagation process and reflected for multiple times to cause resonance and form relatively-uniformly-distributed regular circular light spot modes in a longitudinal distribution manner in a medium recording layer clamped between a metal reflection layer and the probe. According to the surface plasma ultra-diffraction photoetching method based on the tip-insulator-metal structure, the problem that the write-through photoetching depth of a conventional probe is shallow is solved, the sizes of the light spots (full width at half maximum, FWHM) at different depths of the medium recording layer are identical, and the energies are uniform. According to the surface plasma ultra-diffraction photoetching method, the quality of the light spot photoetched by the conventional write-through probe is greatly improved; the structure adopted by the method is simple; and the photoetching line width can be greatly reduced.

Description

technical field [0001] The invention relates to near-field direct writing lithography technology, in particular to a surface plasmon superdiffraction lithography method based on a metal-medium-probe (Tip-Insulator-Metal, TIM) structure, which can effectively improve the quality of the light spot and increase the Lithography depth Background technique [0002] With the rapid development of the information field, the structure size of optoelectronic devices is constantly shrinking, so it is urgently required that the resolution of lithography can break through the limitation of the diffraction limit. Near-field lithography is one of the important fields of research in this area in recent years. By exciting plasmons (SPPs) on the metal surface, the excited SPP wave vector is larger than the wave vector of light in vacuum to achieve the breakthrough of the diffraction limit. Purpose. Among them, probe direct writing lithography is expected to provide a low-cost, high-resolutio...

AI Technical Summary

Problems solved by technology

However, it has the disadvantage that the surface plasmon light field excited for the first time constitutes background interference and the contrast is too low

In addition, the inclined illumination used to excite SP has problems such as asymmetrical light spots, high background light intensity, prism illumination is required, and sample movement may easily lead to illumination changes.

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