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Metallic silicide and its application


Overview of silicides

Metal silicide, especially electric heating element material (MoSi2), has realized industrial production and application. In the early 1940s, it was suggested that metallic silicides such as MoSi2 could be used as high temperature structural materials. Since the end of 1980s, silicide for structure has been studied and developed extensively and deeply in the United States, which has attracted great attention of material workers all over the world. In recent 10 years, it has become a new hotspot in the study of high-temperature structure intermetallic compounds.

Application of silicide

Silicide for electric heating elements: metal silicide is one of its earliest applications as electric heating elements. Generally, the lower the silicon content of metal silicide, the higher the melting point, but its oxidation resistance decreases. Therefore, disilicide with low melting point but good oxidation resistance is usually used to manufacture heating element.

Silicides for high-temperature oxidation resistant Coatings: The remarkable oxidation resistance and self-healing properties of MoSi2 coatings on molybdenum have led to extensive studies of numerous other MeSi2 binary silicides and more complex silicides as oxidation resistant coatings for all refractory metals and their alloys and graphite materials including carbon/carbon composites.

It is known that the thickness of the coating has a parabolic relationship with the time of application, and the effect of application temperature on the thickness of the coating is more sensitive than time. Further study shows that the life of silicide coating is mainly controlled by the interdiffusion ability of elements in the coating system and coating defects. In this aspect, at present, one is to modify the silicide coating by alloying to obtain multiple composite oxide protective film with better oxidation resistance; Second, gradient recombination was used to improve the hair-crack defects of the coating during thermal cycling.

Silicide for gate films of integrated circuits: with the improvement of integrated circuits, the heat resistance of gate and interconnect materials is also increasing. Traditional polysilicon and aluminum materials can not meet the requirements; Although the refractory metals W and Mo have good electrical conductivity and high melting point, they do not resist oxidation, which limits the preparation temperature of integrated circuits. Therefore, refractory metal silicides are paid more attention because of their low resistivity and high stability. The four silicides that have attracted the most attention in this respect are TiSi2, TaSi2, MoSi2 and WSi2, among which TaSi2 is the most stable and its resistivity is lower than WSi2 and MoSi2. At the same time, the metallization of TaSi2 as the gate and interconnect of integrated circuits has its unique advantages, that is, TaSi2 will not be oxidized in dry oxygen. With the advent of ultra-fine particle technology, the requirements for high temperature stability may be reduced, and other silicides will also become useful.

Our company produces more than 20 kinds of silicide products, high purity quality, stable quality, price concessions, welcome to come to inquire, we will send the most sincere service.