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We report the optical design of a solid immersion mirror (SIM) incorporated with a flying slider -called a SIM slider -for a near-field recording (NFR) system, its fabrication process, and optical evaluation. To achieve diffraction-limited performance $=14 (rms), a two-step glass-molding process was employed to fabricate the SIM. The numerical aperture of the SIM slider was 1.29. The rms value of the total wavefront aberration was 0:0679. The fabricated SIM slider achieves the optical performance estimated by calculation with the fabrication errors considered, and even diffraction-limited performance. However, an rms value of 0:035-0:04 for the total wavefront aberration is generally assigned for condensing optics for practical use because not only condensing optics but also other optical elements are involved in a practical optical disc system. Therefore, the aberration caused by the fabrication errors in the molding process should be reduced to at least 59% of the present level, if the SIM is to be applied to a practical NFR system.

On the {1 1 0} solid surface, surface stresses of two perpendicular directions, such as ⟨1 0 0⟩ and ⟨1 1 0⟩, will differ. These different surface stresses cause different equilibrium strains in the ⟨1 0 0⟩ and ⟨1 1 0⟩ directions on a {1 1 0} thin film. In this paper, an analytical formulation is presented to predict the equilibrium strains of orthotropic thin films with {1 0 0}, {1 1 1} or {1 1 0} surfaces. This formulation is composed of the elastic constants of bulk materials and surface parameters such as surface stresses and surface elastic tensors. Transition metals with FCC structures (Cu, Ag, Au, Ni, Pd and Pt) are used in this study, along with a surface relaxation model that calculates surface parameters using atomistic calculations. Molecular dynamics simulations are performed and compared with the results of this suggested method, and both results show good agreement. In addition, size-dependent elastic constants are calculated analytically from the predicted equilibrium state.

The classical model for a thin film, based on continuum theory, is independent of size, and ignores surface effects. But the surface-to-bulk ratio becomes very large in small-scale structures such as nanofilms, nanowires, and nanobeams, and surface effects play an important role. Molecular dynamics simulation has been a conventional way to analyze these ultrathin structures, but structures in the range between submicro and micro are difficult to analyze by molecular dynamics simulation due to the restrictions of computing resources and time. In the present study, a continuum-based, size-dependent model is developed for predicting the thermomechanical properties of nanoscale structures, especially thin films. The proposed continuum-based thin plate finite element is efficient and reliable for the prediction of nanoscale film behavior.

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