Abstract: The switch device comprises a lower electrode, an upper electrode, and a switch material layer disposed between the lower electrode and the upper electrode. When the switch device is in an on state, the switch material layer is in a liquid state and has a bandgap of 0; when the switch device is in an off state, the switch material layer is in a crystalline state, and a Schottky barrier is formed between the switch material layer and the upper electrode, as well as between the switch material layer and the lower electrode. The switch device employs the crystalline-liquid-crystalline phase change mechanism of the switch material, and can drive memory units, such as phase change memory units, resistive memory units, ferroelectric memory units, magnetic memory units, and the like, thereby enabling high-density three-dimensional information storage.

Abstract: The present invention provides a selector material, a selector unit and a preparation method thereof and a memory structure, wherein the selector material comprises at least one of Te, Se and S, that is, the selector material is selected from a simple substance such as Te, Se and S or compounds composed of any of these elements, further, the performance can be improved by doping with elements such as O, N, Ga, In, As and the like, or oxides, nitrides and carbides or other dielectric materials. The selector material in the present invention has the advantages of high turn-on current, simple material, fast switching speed, good repeatability and low toxicity when the selector material is used in the selector unit, which is beneficial to achieving high-density three-dimensional information storage.