Pulse laser deposition based preparation method of phase change film

Abstract

The invention discloses a pulse laser deposition based preparation method of a phase change film. The method is based on pulse laser deposition equipment, and comprises the following steps that under a vacuum condition, lasers are used for irradiating a rotary target material to carry out pre-targeting, and then a Ge2Sb2Se4Te1 film is deposited on a rotary silicon substrate. According to the method, the novel phase change material Ge2Sb2Se4Te1 is prepared through pulsed laser deposition, it is guaranteed that all elements in the alloy film are in a quite ideal component ratio, the refractive index change condition of the Ge2Sb2Se4Te1 in the gradual phase change process is achieved through annealing at the specific temperature and the specific time, the goodness value FOM is equal to 5.2 at the position of 1550 nm, the goodness value is the ratio of the change of the refractive index to the change of the extinction coefficient before and after phase change, and the phase change performance of the phase change material is reflected. For the novel phase change material Ge2Sb2Se4Te1 prepared based on pulsed laser deposition, the morphology change before and after phase change and the lattice structure under the crystalline state condition are researched, the change condition of the chemical attitude of the elements before and after phase change is analyzed, and the phase change mechanism of Ge2Sb2Se4Te1 is disclosed.

Description

technical field [0001] The invention relates to the technical field of thin film deposition, in particular to a preparation method of a phase change thin film based on pulsed laser deposition. Background technique [0002] Optical phase change materials (OPCM) are a group of unique materials, because of the huge contrast of optical properties before and after the phase change (crystalline state and amorphous state), in the fields of optical switches, image displays, optical storage and all-optical computers has been widely used. Chalcogenide phase change materials Phase change materials mainly include monobasic (Te-based, Sb-based), binary (SbTe-based, GeTe-based) and ternary-based (GeSbTe-based), Ge 2 Sb 2 Te 5 It has attracted widespread attention because of its nanosecond phase transition and the huge difference in optical constants (Δn>2.5) before and after the phase transition. With the increasing demand for chalcogenide phase change materials in the fields of op...

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Problems solved by technology

However, other than that when Ge 2 Sb 2 Te 5 When applied to integrated photonics devices, the extinction coefficients of amorphous and crystalline states at 1550nm are as high as 0.12 and 1.49, respectively (Stegmaier M, CarlosR, Bhaskaran H, et al.NonvolatileAll-Optical 1×2Switch for Chipscale PhotonicNetworks[ J].Advanced Optical Materials,2016,5(1):1600346.), resulting in high optical wave transmission loss in the optical waveguide device made of this material in the important communication band

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