Mg2Si Magnesium Silicide

Mg2Si Magnesium Silicide

Chinese name magnesium silicide

English Name: magnesium silicon

Also known as metals basis

Chemical formula mg Ψ Si

The molecular weight is 76.71 CAS

Accession number 22831-39-6

Melting point 1102 ℃

Insoluble in water and denser than water

Density: 1.94g/cm

Application: Mg2Si is the only stable compound of Mg Si binary system. It has the characteristics of high melting point, high hardness and high elastic modulus. It is a narrow band gap n-type semiconductor material. It has important application prospects in optoelectronic devices, electronic devices, energy devices, laser, semiconductor manufacturing, constant temperature control communication and other fields.

Magnesium silicide (Mg2Si) is an indirect semiconductor with narrow band gap. At present, the microelectronics industry is mainly based on Si materials. The process of growing Mg2Si thin film on Si substrate is compatible with Si process. Therefore, Mg2Si / Si Heterojunction structure has great research value. In this paper, environment-friendly Mg2Si thin films were prepared on Si substrate and insulating substrate by magnetron sputtering. The effect of sputtering mg film thickness on the quality of Mg2Si thin films was studied. On this basis, the preparation technology of Mg2Si based heterojunction LED devices was studied, and the electrical and optical properties of Mg2Si thin films were studied. Firstly, Mg films were deposited on Si substrates by magnetron sputtering at room temperature, Si films and Mg films were deposited on insulating glass substrates, and then Mg2Si films were prepared by heat treatment in low vacuum (10-1pa-10-2pa). The results of XRD and SEM show that the single phase Mg2Si thin film is prepared by annealing at 400 ℃ for 4h, and the prepared Mg2Si thin film has dense, uniform and continuous grains, smooth surface and good crystallinity. Secondly, the effect of the thickness of Mg film on the growth of Mg2Si semiconductor film and the relationship between the thickness of Mg film and the thickness of Mg2Si film after annealing were studied. The results show that when the thickness of Mg film is 2.52 μ m and 2.72 μ m, it shows good crystallinity and flatness. The thickness of Mg2Si film increases with the increase of Mg thickness, which is about 0.9-1.1 times of that of Mg. This study will play an important role in guiding the design of devices based on Mg2Si thin films. Finally, the fabrication of Mg2Si based heterojunction light emitting devices is studied. Mg2Si / Si and Si / Mg2Si / Si Heterojunction LED devices are fabricated on Si substrate. The electrical and optical properties of Mg2Si / Si and Si / Mg2Si / Si heterostructures are studied by means of four probe test system, semiconductor characteristic analyzer and steady / transient fluorescence spectrometer. The results show that: the resistivity and sheet resistance of Mg2Si thin films decrease with the increase of Mg2Si thickness; Mg2Si / Si and Si / Mg2Si / Si heterostructures show good unidirectional conduction characteristics, and the on voltage of Si / Mg2Si / Si double heterostructure structure is about 3 V; the photoluminescence intensity of Mg2Si / n-Si heterojunction device is the highest when the wavelength is 1346 nm. When the wavelength is 1346 nm, the photoluminescence intensity of Mg2Si thin films prepared on insulating substrates is the highest; compared with the photoluminescence of Mg2Si thin films prepared on different substrates, the Mg2Si films prepared on high-purity quartz substrate have better luminescence performance and infrared monochromatic luminescence characteristics.