Aluminium Arsenide - What Is It? How Does it Work?

Aluminum arsenide is a kind of inorganic compound, chemical formula is AlAs, is orange yellow crystal, when dissolved in acid produces hydrogen arsenide gas, commonly used as a spectral analysis reagent and raw material for the preparation of electronic components, is also a new type of semiconductor material.

Basic information about aluminum arsenide

CAS No. : 22831-42-1

Formula: AlAs

Molecular weight: 101.90

Exact molecular weight: 105.93400

EINECS: 245-255-0

Properties: semiconductor, sphalerite structure.

Density: 3.81 g/mL

Melting point: 1740 ºC

Water-soluble: reacts with water

Appearance: orange crystal

Preparation of aluminum arsenide

The invention relates to an efficient method for preparing high purity aluminum arsenide. The method adopts vapor deposition method. Under the protection of argon gas, the aluminum trichloride and arsenic trichloride are heated respectively in the volatilization chamber to volatilize into steam, which is sprayed into the reaction chamber through a nozzle to react and generate aluminum arsenide crystal by vapor deposition. The specific steps are as follows:

(1) Using argon as a protective gas, aluminum trichloride and arsenic trichloride were extracted according to the molar mass ratio of 1:1 ~ 1.5:1, respectively in the first volatile chamber 1 and the second volatile chamber 2, and volatilized at 300 ~ 900℃ for 0.5h ~ 12h, so that the two materials were in vapor state;

(2) The aluminum trichloride and arsenic trichloride vapors in the two volatilization chambers were injected into a titanium reaction chamber 3 through the first nozzle 4 and the second nozzle 5 at the same time through the first nozzle 4 and the second nozzle 5 respectively, and the reaction of chemical bookh ~ 5h at 300 ~ 900℃ was conducted to obtain the deposits by vapor deposition; The remaining volatile gas is pressurized to 600 ~ 700kPa at normal temperature or cooled to -34℃ at normal pressure to obtain liquid chlorine.

(3) The obtained sediment was heated for 2h ~ 12h at 300 ~ 900℃ and pressure of 0.5 ~ 100KPa. The residual chlorine was removed and cooled to obtain orange crystal aluminum arsenide with purity greater than 99.9%. The first volatile chamber 1 and the second volatile chamber 2 can adopt the metal heating volatile equipment of the existing technology, such as the side-blowing electric furnace, and connect the nozzle of the opposite reaction chamber in the eye of the electric furnace. The reaction chamber can also use electric heating furnace, vapor deposition to get sediment; The remaining volatile gas is extracted from the reaction chamber, which is pressurized to 600 ~ 700kPa at normal temperature or cooled to -34℃ at normal pressure to obtain liquid chlorine.

Properties and stability of aluminum arsenide

It will not decompose if used and stored according to specifications

Avoid exposure to acids

The dielectric constant is 10.3.

Band gap 2.13eV(22℃).

Storage method of aluminum arsenide

Keep the cache sealed

Store in a tight container in a cool, dry place

Application of aluminum arsenide

It is often used as a reagent for spectral analysis and raw material for preparing electronic components. It is also a new type of semiconductor material.