The present disclosure provides a method and system for fabricating a semiconductor device. The method and system of the present disclosure, after obtaining the polysilicon layer, first form the protective oxide layer on the surface of the polysilicon layer, and then etch the protective oxide layer and the protrusions on the surface of the polysilicon layer with the buffered oxide etchant based on controllability of the buffered oxide etchant, thereby reducing the protrusions on the surface of the polysilicon layer, while well protecting the surface of the polysilicon layer. Therefore, the technical problem of surface roughness in the existing polysilicon layers is solved.

The present disclosure provides a method and system for fabricating a semiconductor device. The method and system of the present disclosure, after obtaining the polysilicon layer, first form the protective oxide layer on the surface of the polysilicon layer, and then etch the protective oxide layer and the protrusions on the surface of the polysilicon layer with the buffered oxide etchant based on controllability of the buffered oxide etchant, thereby reducing the protrusions on the surface of the polysilicon layer, while well protecting the surface of the polysilicon layer. Therefore, the technical problem of surface roughness in the existing polysilicon layers is solved.

A MOD YIG epitaxial process for fabricating YIG nanofilms which, when deposited on GGG substrates, have single crystal epitaxial properties. The films may have thicknesses of 50 nm for a single layer, 100 nm for two layers, and 130 nm for three layers, and have a gyromagnetic ratio of 2.80 MHz per Oe, Gilbert damping ranges from 0.0003 to 0.001, 4M$ values between 1650 G to 1780 G, coercivity from 1 Oe. to 5 Oe, and surface roughness of RMS 0.20 nm for up to 10 layers. Fabrication is economical and uses only a spinner, a drying station (RT to 150 C temperature control), and a quartz tube furnace that accommodates a flowing atmosphere of research grade oxygen, thereby eliminating the need for high vacuum deposition chambers.

The present invention relates to a method for manufacturing a monocrystalline metal foil and a monocrystalline metal foil manufactured thereby, the method comprising the steps of: fixing each of the ends of polycrystalline metal foil to electrodes; and heat-treating the fixed polycrystalline metal foil to manufacture a monocrystalline metal foil.

A method for making MnBi.sub.2Te.sub.4 single crystal is provided. The method includes: providing a mixture of polycrystalline MnTe and polycrystalline Bi.sub.2Te.sub.3 in Molar ratio of 1.1:11:1.1; heating the mixture in a vacuum reaction chamber to 700 C.900 C., cooling the mixture to 570 C.600 C. slowly with a speed less than or equal to 1 C./hour, and annealing the mixture at 570 C.600 C. for a time above 10 days to obtain an intermediate product; and air quenching the intermediate product from 570 C.600 C. to room temperature. The method for making MnBi.sub.2Te.sub.4 single crystal is simple and has low cost.

A method for making MnBi.sub.2Te.sub.4 single crystal is provided. The method includes: providing a mixture of polycrystalline MnTe and polycrystalline Bi.sub.2Te.sub.3 in Molar ratio of 1.1:11:1.1; heating the mixture in a vacuum reaction chamber to 700 C.900 C., cooling the mixture to 570 C.600 C. slowly with a speed less than or equal to 1 C./hour, and annealing the mixture at 570 C.600 C. for a time above 10 days to obtain an intermediate product; and air quenching the intermediate product from 570 C.600 C. to room temperature. The method for making MnBi.sub.2Te.sub.4 single crystal is simple and has low cost.

A method for making MnBi.sub.2Te.sub.4 single crystal is provided. The method includes: providing a mixture of polycrystalline MnTe and polycrystalline Bi.sub.2Te.sub.3 in Molar ratio of 1.1:11:1.1; heating the mixture in a vacuum reaction chamber to 700 C.900 C., cooling the mixture to 570 C.600 C. slowly with a speed less than or equal to 1 C./hour, and annealing the mixture at 570 C.600 C. for a time above 10 days to obtain an intermediate product; and air quenching the intermediate product from 570 C.600 C. to room temperature. The method for making MnBi.sub.2Te.sub.4 single crystal is simple and has low cost.

A method for making MnBi.sub.2Te.sub.4 single crystal is provided. The method includes: providing a mixture of polycrystalline MnTe and polycrystalline Bi.sub.2Te.sub.3 in Molar ratio of 1.1:11:1.1; heating the mixture in a vacuum reaction chamber to 700 C.900 C., cooling the mixture to 570 C.600 C. slowly with a speed less than or equal to 1 C./hour, and annealing the mixture at 570 C.600 C. for a time above 10 days to obtain an intermediate product; and air quenching the intermediate product from 570 C.600 C. to room temperature. The method for making MnBi.sub.2Te.sub.4 single crystal is simple and has low cost.

Fabricating a crystalline metal-phosphide layer may include providing a crystalline base substrate and a step of forming a crystalline metal-source layer. The method may further include performing a chemical conversion reaction to convert the metal-source layer to the crystalline metal phosphide layer. One or more corresponding semiconductor structures can be also provided.

Fabricating a crystalline metal-phosphide layer may include providing a crystalline base substrate and a step of forming a crystalline metal-source layer. The method may further include performing a chemical conversion reaction to convert the metal-source layer to the crystalline metal phosphide layer. One or more corresponding semiconductor structures can be also provided.