The preparation method proposed by Ningbo International Material Genetic Engineering Research Institute Co., Ltd. can complete the preparation of amorphous materials in a relatively short time and at a low temperature, which greatly reduces the preparation cost of amorphous materials and improves the preparation efficiency .
New material technology is regarded as the "mother of invention" and "industrial food". Recently, domestic universities have published relevant research results on amorphous materials in the "Nature" magazine, and once again promoted amorphous materials To the hot spot of semiconductor research.
Amorphous material is an aggregated material with a degree of order between crystal and liquid. Amorphous material does not have perfect short-range and long-range order like crystalline matter, but there is no long-range order. Only has short-range order. There are two problems to be solved in the preparation of amorphous materials: one is to form a disordered arrangement of atoms or molecules, and the thermodynamic metastable state of the amorphous material must be preserved within a certain temperature range so that it does not To the crystalline state.
In the preparation of amorphous precursors, since the multi-layer film system adopts two processes of diffusion and crystallization nucleation at the interface of different materials, once nucleation, it is not easy to further diffuse. However, if the thickness of the prepared film is not below the critical thickness of diffusion-crystallization, the generation of intermediate compounds during heat treatment cannot be avoided, which hinders the completion of diffusion. This requires additional experiments to explore the critical thickness of diffusion-crystallization of different thin-film materials. In order to control the critical thickness of the deposited thin film during the experiment, the experiment workload is increased and the experiment efficiency is reduced.
In order to solve the above-mentioned problems, Ningbo International Material Genetic Engineering Research Institute Co., Ltd. applied for an invention patent called "A method for preparing amorphous materials" as early as 16 years (application number: 201610050104.2), and the applicant was Ningbo International Materials Genetic Engineering Research Institute Co., Ltd.
The patent provides a preparation method with high experimental efficiency, which can complete the uniform mixing of various materials through a simple material deposition process and a low-temperature heat treatment process, and then complete the preparation of amorphous materials.
Due to the wide variety of amorphous materials, here we take the preparation method of iron-boron-aluminum (Fe-B-Al) amorphous alloy material as an example. In the preparation process of Fe-B-Al amorphous alloy materials, for Fe and Al materials, we use the magnetron sputtering method for thin film deposition, while for B material, we choose electron beam evaporation method for thin film deposition.
First, in a vacuum environment, adjust the deposition power of the Fe material deposition source, and at the same time adjust the distance between the Fe material deposition source and the substrate, and deposit the Fe material film on the substrate by the magnetron sputtering method to ensure that the substrate is deposited. The thickness of the Fe material film in this layer is much smaller than the critical thickness of the diffusion-crystallization of the Fe material, and finally the thickness of the Fe material film is 1.5 nm.
The deposition power of the B material deposition source is adjusted accordingly, and the distance between the B material deposition source and the substrate is adjusted at the same time, and the B material film deposition is performed on the Fe material film by electron beam evaporation, and the layer deposited on the substrate is ensured The thickness of the B material film is much smaller than the critical thickness of the diffusion and crystallization of the B material.
When preparing the Al material film, the same preparation method as the Fe material film is used, except that the desired thickness of the Al material film is about 1.8 nm.
Finally, the above operations are repeated in sequence until the total thickness of the deposited Fe-B-Al thin film reaches the required thickness, thereby preparing a FeB-Al-Fe-B-Al … superlattice structure multilayer film sample. Under the control of a common water cooling device, the above-mentioned Fe-B-Al-Fe-B-Al … superlattice structure multilayer film sample preparation process was placed at room temperature. Then, the prepared Fe-B-Al-Fe-B-Al … superlattice structure multi-layer film sample is placed in an environment of 100 ° C and atmospheric pressure for 3 hours of heat treatment to complete Fe-B-Al Preparation of amorphous samples.
The preparation method proposed by Ningbo International Material Genetic Engineering Research Institute Co., Ltd. can complete the preparation of amorphous materials in a relatively short time and at a low temperature, which greatly reduces the preparation cost of amorphous materials and improves the preparation efficiency .
Internationally, the United States, Japan, Germany and other countries have invested a lot of money to support the research of amorphous materials and promote industrial development. China's scientific research workers are also keeping up with the world's development frontiers, and have made breakthrough progress in many directions in the amorphous field, with considerable scientific research results. It is hoped that in the near future, more amorphous materials will be used in real life, and we hope that the research of new semiconductor materials in China will create more glories.