Currently, the most widely used photoresists in optical lithography are organic-based resists. The major limitations of such resists include the photon accumulation severely affects the quality of photolithography patterns and the size of the pattern is constrained by the diffraction limit. Phase-change lithography, which uses semiconductor-based resists such as chalcogenide Ge2Sb2Te5 films, was developed to overcome these limitations. Here, instead of chalcogenide, we propose a metallic resist composed of Mg58Cu29Y13 alloy films, which exhibits a considerable difference in etching rate between amorphous and crystalline states. Furthermore, the heat distribution in Mg58Cu29Y13 thin film is better and can be more easily controlled than that in Ge2Sb2Te5 during exposure. We succeeded in fabricating both continuous and discrete patterns on Mg58Cu29Y13 thin films via laser irradiation and wet etching. Our results demonstrate that a metallic resist of Mg58Cu29Y13 is suitable for phase change lithography, and this type of resist has potential due to its outstanding characteristics.

A model of an optical disk containing data pits with a range of depths and orientation angles is simulated to investigate how the Stokes parameters of the light reflected from these pits vary. Pits carrying multiple bits of information can be recovered according to the Stokes parameters, particularly S0 and S1, which show different variation trends versus the depth and orientation angles. In addition, the signal width of S0 ceases to be constant, and instead varies as a function of the orientation angle during laser scanning. This can double the available modulation range of the orientation angle and further enhance disk storage densities.

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