Synthesis and characterization of new low molecular weight aluminum organometallic complexes using amino/imine type ligands with possible uses in Atomic Layer Deposition processes

Abstract

The driver of development and innovation in the microelectronics industry is the miniaturization of the components that make up each technological node. This miniaturization has given rise to new challenges for traditional materials and the need for new fabrication methods with sub-nanometer precision.Based on this, numerous methods have emerged for the fabrication of this type of nanometer materials, among which chemical deposition processes stand out. An industrial example of this type of chemistry is the so-called ALD (Atomic Layer Deposition), which generates deposition of nanometric metal layers, using precursors in a gaseous state.The use of metallic precursors in gaseous state, generates that the process has as a key factor the correct molecular design of the inorganic/organometallic material, since the method imposes strict requirements to the chemical and physical properties of these compounds, such as thermal stability, volatility, synthetic scaling, among others. With this in mind, in this research, new aluminum complexes were synthesized using TMA and imino/amine type ligands with low molecular weight substituents (isopropyl, tertbutyl), to generate stable and volatile liquid complexes in inert atmosphere at room temperature.Finally, four liquid complexes are obtained, stable in nitrogen atmosphere, with yields of 70%. Due to the mentioned characteristics, these complexes could be used as precursors for the deposition of Al and Al2O3 films. In addition, it is demonstrated that the use of TMA in this type of ligands can generate a methylation in the chain of this molecule, which opens a new field in the development of aluminum organometallic complexes.