Trimethylaluminum (TMAl), as a metal-organic (MO) source, is widely utilized in the semiconductor industry and serves as a key precursor for atomic layer deposition (ALD), chemical vapor deposition (CVD), and metal-organic chemical vapor deposition (MOCVD). It is employed to prepare high-purity aluminum-containing films, such as aluminum oxide and aluminum nitride. Additionally, TMAl finds extensive application as a catalyst and its auxiliary agent in organic synthesis and polymerization reactions.
Trimethylaluminum (TMAI) acts as a precursor for aluminum oxide deposition and functions as a Ziegler-Natta catalyst. It is also the most commonly used aluminum precursor in the production of metal-organic vapor-phase epitaxy (MOVPE). Furthermore, TMAI serves as a methylation agent and is frequently released from sounding rockets as a tracer for studying upper atmospheric wind patterns.
Trimethylalumane(TMAI)
| Synonyms |
Trimethylaluminum, Aluminium Trimethyl,Aluminum Trimethanide, TMA, TMAL, AlMe3, Ziegler-Natta Catalyst, Trimethyl-, Trimethylalane. |
| Cas Number |
75-24-1 |
| Chemical formula |
C6H18Al2 |
| Molar mass |
144.17 g/mol, 72.09 g/mol (C3H9Al) |
| Appearance |
Colorless liquid |
| Density |
0.752 g/cm3 |
| Melting point |
15℃ (59 ℉; 288K) |
| Boiling point |
125–130℃ (257–266 ℉, 398–403K) |
| Solubility in water |
Reacts |
| Vapor pressure |
1.2 kPa (20℃), 9.24 kPa (60℃) |
| Viscosity |
1.12 cP (20℃), 0.9 cP (30℃) |
What is Trimethylaluminum (TMAI) used for?
Catalysis Applications:
Since the invention of Ziegler-Natta catalysis, organoaluminum compounds have played a pivotal role in the production of polyolefins, including polyethylene and polypropylene. Methylaluminoxane (MAO), derived from trimethylaluminum (TMA), serves as an activator for numerous transition metal catalysts in polymerization processes.
Semiconductor Applications:
Trimethylaluminum (TMA) is extensively utilized in semiconductor fabrication for depositing thin films of high-k dielectrics, such as aluminum oxide (Al2O3), through chemical vapor deposition (CVD) or atomic layer deposition (ALD). In the semiconductor industry, high-purity TMA functions as an aluminum precursor in ALD or CVD processes to generate Al2O3 thin films as high-k dielectric materials. Additionally, TMA is the preferred precursor for metalorganic vapor phase epitaxy (MOVPE) of aluminum-containing compound semiconductors, such as aluminum arsenide (AlAs), aluminum nitride (AlN), aluminum phosphide (AlP), aluminum antimonide (AlSb), aluminum gallium arsenide (AlGaAs), aluminum indium gallium arsenide (AlInGaAs), aluminum indium gallium phosphide (AlInGaP), aluminum gallium nitride (AlGaN), aluminum indium gallium nitride (AlInGaN), and aluminum indium gallium nitride phosphide (AlInGaNP). The quality criteria for TMA focus on (a) elemental impurities, (b) oxygenated impurities, and (c) organic impurities.
Photovoltaic Applications:
In the photovoltaic industry, TMA is employed to form aluminum oxide (Al2O3) passivation layers via plasma-enhanced chemical vapor deposition (PECVD) or atomic layer deposition (ALD). Similar to semiconductor processing, TMA is used to deposit thin-film, low-k (non-absorbing) dielectric layer stacks containing Al2O3 through CVD or ALD processes. High-purity TMA enhances the efficiency of crystalline silicon solar cells by creating effective Al2O3 passivation layers, thereby improving performance.
LED Applications:
In LED manufacturing, high-purity TMA is utilized via MOVPE or CVD to fabricate aluminum-containing compound semiconductors, such as aluminum gallium nitride (AlGaN) epitaxial layers, or aluminum oxide (Al2O3) and aluminum nitride (AlN) passivation layers. This improves optical efficiency and provides superior illumination performance.
