Gallium telluride (Ga₂

Gallium

Gallium is a chemical element that has the symbol Ga and atomic number 31. Elemental gallium does not occur in nature, but as the gallium salt in trace amounts in bauxite and zinc ores. A soft silvery metallic poor metal, elemental gallium is a brittle solid at low temperatures. As it liquefies...

Te₃) is a chemical compound

Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 classified as a metal telluride. At room temperature gallium(III) telluride is an odorless, black, brittle crystalline solid and is a semiconductor

Semiconductor

A semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...

 of the III-VI type that crystallizes in a lattice structure.

Synthesis

Gallium(III) telluride is most commonly synthesized through the solid-state reaction of trimethylgallium

Trimethylgallium

Trimethylgallium, Ga3, often abbreviated to TMG or TMGa, is the preferred metalorganic source of gallium for metalorganic vapour phase epitaxy of gallium-containing compound semiconductors, such as GaAs, GaN, GaP, GaSb, InGaAs, InGaN, AlGaInP, InGaP and AlInGaNP.-Properties:TMG is a clear,...

 and a telluride oxide complex under high temperatures. It is also possible to synthesize the compound by reacting elemental gallium

Gallium

Gallium is a chemical element that has the symbol Ga and atomic number 31. Elemental gallium does not occur in nature, but as the gallium salt in trace amounts in bauxite and zinc ores. A soft silvery metallic poor metal, elemental gallium is a brittle solid at low temperatures. As it liquefies...

 and elemental tellurium at high temperatures.

Physical Properties

At room temperature Gallium (III) telluride is a black, odorless, brittle crystal. The compound crystallizes in a four-coordinate tetrahedral structure. The crystal is not immediately reactive or flammable, though serious protective ware should be worn while handling this compound (see toxicity). Gallium (III) telluride has a melting point of 788 oC to 792 oC and is not soluble in water.

Chemical Properties

Gallium (III) telluride is stable at room temperature. The compound is relatively un-reactive, and there are no known materials with which it is incompatible. Gallium (III) telluride will over time emit telluride

Telluride (chemistry)

The telluride ion is Te2−. It is the final stable member of the series of dianions O2−, S2−, and Se2− ....

 fumes and it naturally decomposes. There is no risk of hazardous polymerization

Hazardous polymerization

Radical polymerization of pure styrene causes the viscosity to increase. This retards the deactivation of the free radicals by radical-radical reactions, but it does not have such a great effect on the reaction of the radicals with styrene. Hence the concentration of free radicals increases and the...

.

Toxicity

The toxicological properties of Gallium (III) telluride have not been thoroughly investigated. However elemental tellurium has relatively low toxicity. It is converted in the body to dimethyl telluride which imparts a garlic-like odor to the breath and sweat. Heavy exposures may, in addition, result in headache, drowsiness, metallic taste, loss of appetite, nausea, tremors, convulsions, and respiratory arrest. Proper precautions should be taken when handling this compound, including lab goggles and safety gloves. This compound should be handled in a well ventilated area.

Industrial

Gallium (III) telluride is a p-type semiconductor

Semiconductor

A semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...

 of the III-IV type. Currently its use in industry is relatively limited but further application are being explored, especially as its use in a thin film and for applications in laser diodes and solar cells.

Other Uses

Gallium (III) telluride has been used in the production of sputtering

Sputtering

Sputtering is a process whereby atoms are ejected from a solid target material due to bombardment of the target by energetic particles. It is commonly used for thin-film deposition, etching and analytical techniques .-Physics of sputtering:...

 targets, used for semiconductor

Semiconductor

A semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...

, chemical vapor deposition

Chemical vapor deposition

Chemical vapor deposition is a chemical process used to produce high-purity, high-performance solid materials. The process is often used in the semiconductor industry to produce thin films. In a typical CVD process, the wafer is exposed to one or more volatile precursors, which react and/or...

 (CVD) and physical vapor deposition

Physical vapor deposition

Physical vapor deposition is a variety of vacuum deposition and is a general term used to describe any of a variety of methods to deposit thin films by the condensation of a vaporized form of the desired film material onto various workpiece surfaces...

(PVD) display and optical applications. High-purity gallium(III) telluride is commercially available in many crystalline and polycrystalline forms.