Trimethylgallium
Encyclopedia
Trimethylgallium, Ga3, often abbreviated to TMG or TMGa, is the preferred metalorganic source of gallium
for metalorganic vapour phase epitaxy
(MOVPE) of gallium-containing compound semiconductor
s, such as GaAs, GaN, GaP, GaSb, InGaAs
, InGaN
, AlGaInP
, InGaP
and AlInGaNP.
(i.e. proton
s). Therefore, TMG needs to be handled with care and caution, e.g. stored in a cool, dry place at 0-25 °C, under inert
atmosphere, and ensuring that storage temperatures would not exceed 40 °C to avoid deterioration.
with gallium trichloride
. The less volatile diethyl ether adduct can be prepared by using methylmagnesium iodide in ether in place of dimethylzinc; the ether ligands may be displaced with liquid ammonia as well.
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...
for metalorganic vapour phase epitaxy
Metalorganic vapour phase epitaxy
Metalorganic vapour phase epitaxy , also known as organometallic vapour phase epitaxy or metalorganic chemical vapour deposition , is a chemical vapour deposition method of epitaxial growth of materials, especially compound semiconductors, from the surface reaction of organic compounds or...
(MOVPE) of gallium-containing compound semiconductor
Compound semiconductor
A compound semiconductor is a semiconductor compound composed of elements from two or more different groups of the periodic table . These semiconductors typically form in groups 13-16 ,...
s, such as GaAs, GaN, GaP, GaSb, InGaAs
Indium gallium arsenide
Indium gallium arsenide is a semiconductor composed of indium, gallium and arsenic. It is used in high-power and high-frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide. InGaAs bandgap also makes it the...
, InGaN
Indium gallium nitride
Indium gallium nitride is a semiconductor material made of a mix of gallium nitride and indium nitride . It is a ternary group III/group V direct bandgap semiconductor. Its bandgap can be tuned by varying the amount of indium in the alloy...
, AlGaInP
Aluminium gallium indium phosphide
Aluminium gallium indium phosphide is a semiconductor material.AlGaInP is used in manufacture of light-emitting diodes of high-brightness red, orange, green, and yellow color, to form the heterostructure emitting light...
, InGaP
Indium gallium phosphide
Indium gallium phosphide , also called gallium indium phosphide , is a semiconductor composed of indium, gallium and phosphorus...
and AlInGaNP.
Properties
TMG is a clear, colorless, pyrophoric liquid. Even the hydrocarbon solutions of TMG, when sufficiently saturated, are known to catch fire on exposure to air. TMG is known to react violently with water and other compounds that are capable of providing labile and active hydrogenHydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
(i.e. proton
Proton
The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number....
s). Therefore, TMG needs to be handled with care and caution, e.g. stored in a cool, dry place at 0-25 °C, under inert
Inert
-Chemistry:In chemistry, the term inert is used to describe a substance that is not chemically reactive.The noble gases were previously known as inert gases because of their perceived lack of participation in any chemical reactions...
atmosphere, and ensuring that storage temperatures would not exceed 40 °C to avoid deterioration.
Preparation
Trimethylgallium may be prepared by the reaction of dimethylzincDimethylzinc
Dimethylzinc, also known as Zinc methyl, DMZ, or DMZn is a colorless mobile liquid Zn2, formed by the action of methyl iodide on zinc at elevated temperature or on zinc sodium alloy....
with gallium trichloride
Gallium trichloride
Gallium trichloride is the chemical compound with the formula GaCl3. Solid gallium trichloride exists as a dimer with the formula Ga2Cl6. It is colourless and soluble in virtually all solvents, which is unusual for a metal halide. It is the main precursor to most derivatives of gallium and a...
. The less volatile diethyl ether adduct can be prepared by using methylmagnesium iodide in ether in place of dimethylzinc; the ether ligands may be displaced with liquid ammonia as well.