Niobium pentoxide target：Properties, Applications, and Benefits

Niobium pentoxide, chemical formula Nb2O5, turns yellow when heated to 400°C, soluble in hydrofluoric acid, hot sulfuric acid and alkali, insoluble in water and is the most stable oxide. The chemical formula of its hydrate is Nb2O5 xH2O, which can be decomposed by heat, soluble in concentrated sulfuric acid, concentrated hydrochloric acid, hydrofluoric acid and strong alkali, insoluble in water and ammonia, and can be obtained by burning metal niobium in air or dehydrating niobic acid. 

Physicochemical properties of niobium pentoxide

CAS: 1313-96-8/12627-00-8

EINECS: 215-213-6

Melting point: 1520 °C 

Molecular formula: Nb2O5 

Molecular weight: 265.810

Specific gravity: 4.6

Relative permittivity: 35-50

Bandgap: 3.4eV.

Insoluble in water, hardly soluble in acid, soluble in molten potassium bisulfate or alkali metal carbonate, hydroxide.

Plasma Spraying Niobium Oxide Process Flow

The process flow of plasma spraying niobium oxide is high-purity niobium pentoxide, centrifugal atomization (granulation, sintering, milling, screening, inspection, and storage of finished products. Plasma spraying is a technology for surface strengthening and surface modification of materials. It can make the surface of the substrate have properties such as wear resistance, corrosion resistance, high temperature oxidation resistance, electrical insulation, heat insulation, radiation protection, wear reduction and sealing. Plasma spraying is also used for medical purposes, spraying a layer of tens of microns on the surface of artificial bones Coatings as a means of strengthening artificial bones and enhancing their affinity.

As a commonly used high refractive index material, what materials can Nb2O5 be used for sputtering?

Ta2O5 is also a commonly used high-refractive index material. It can be seen that it is transparent in the infrared band, but whether it is deposited by electron gun or sputtered coating (Ta target), it is more stable than TiO2 by plating. Ta2O5 plus 7%wt Ta is used as When the initial film material is used, the coating is more stable. According to the experience of electron gun plus ion-assisted coating and sputtering coating (Ta target), coating Ta2O5 is easier to obtain a thin film with smaller absorption and scattering than TiO2 film, and the deposition rate of the film can also be faster. , the stacking density is close to 1, so it is often used together with SiO2 for multi-layer optical filter plating.

The refractive index of Nb2O5 is between TiO2 and Ta2O5, and it is transparent in the near-ultraviolet to infrared bands. Sputtering Nb targets, or electron gun plus ion-assisted evaporation of Nb2O5 can be used to obtain excellent optical films with a packing density close to 1, but Its pre-melting before coating is very important. In the past, Nb2O5 was used less, but now it is used more and more. It is used together with SiO2 to coat multi-layer filters. The price of Nb2O5 is much lower than Ta2O5.

The application of niobium pentoxide

Niobium pentoxide is used as nickel niobate single crystal to make special optical glass, high-frequency and low-frequency capacitors and piezoelectric ceramic components. It is also used in the production of ferroniobium and various niobium alloys required for special steel. It is the raw material for producing niobium and its compounds. It is also used as catalyst and refractory material.

Niobium oxide Nb2O5 rotating target

The niobium oxide Nb2O5 target is made of niobium oxide Nb2O5 powder, which is mixed with water and a binder, processed through a series of production processes, and then sintered in a high temperature atmosphere (1200 degrees, sintered with argon gas). Niobium oxide Nb2O5 targets are widely used in the manufacture of anti-reflection coatings and thin-film solar cells. Its molecular weight is 266 and its theoretical density is 4.47g/cm3. The melting point is 1485°C±5°C. Insoluble in water, hardly soluble in acid, soluble in molten potassium bisulfate or alkali metal carbonate, hydroxide. Dissolution: Insoluble in water, insoluble in other acids except sulfuric acid and hydrofluoric acid. Can not be sintered in the atmosphere.

The current production process is vacuum hot pressing sintering. This method can only produce planar niobium oxide Nb2O5 targets, and the material utilization rate of planar targets is very low, only about 25%. The cost of coating materials is high. If the hot pressing method is not used, the sintered density is only about 85%, and problems such as arcing and high impurity content will occur during use, and high-quality anti-reflection layers cannot be produced. These adverse factors will seriously affect the quality of the film, resulting in uneven structure of the film and low purity of the components. Compared with the planar target, the utilization rate of the niobium oxide rotating target with high purity, high density, uniform composition and no macro defects is increased from about 40% of the planar target to about 80% by plasma spraying, which greatly saves the cost of raw materials. Wood. At the same time, the rotating target greatly increases the coating area and improves the coating performance quality and coating efficiency in the magnetron sputtering technology.