Gas phase studies of new copper(I) carboxylates compounds with vinylsilanes and their application in Chemical Vapor Deposition (CVD)

Copper(I) carboxylate compounds with vinylsilanes of the general formula [Cu(L)(μ-O2CR)]n, where L = CH2C(H)SiMe3, CH2C(H)SiEt3, CH2C(H)Si(OMe)3; R = CF3, C2F5; n = 2 or 3, have been synthesized and characterized in the solid state and in the gas phase by variable temperature IR spectroscopy, mass spectrometry and thermal analysis. Complexes are di- or trimeric species with bridging carboxylates and dihapto coordinated vinylsilanes. Electron impact mass spectra indicate metallated species in the gas phase, of which the [Cu2(O2CR)]+ and [Cu2(O2CR)2]+· ions revealed the highest intensity. Similar copper(I) carboxylates derivatives [Cu2(O2CR)2] were detected in the vapors by variable temperature IR spectral analysis, which suggests that these species can be transported in the CVD process. The vaporization temperature of the metallated fragments was lower in the case of [Cu(L)(μ-O2CC2F5)]n than for the [Cu(L)(μ-O2CCF3)]2 complexes, therefore [Cu(CH2C(H)SiMe3)(μ-O2CC2F5)]n and [Cu(CH2C(H)SiEt3)(μ-O2CC2F5)]n have been selected for CVD experiments. Considering the results of the TGA, MS and variable temperature IR studies, the thermal decomposition pathway and the mechanism of the Cu layers formation are proposed. Copper layers were deposited by Chemical Vapor Deposition and characterized by XRD and SEM methods. The morphology of the copper layers depends on the properties of the used substrates: Si(1 1 1), stainless steel, ITO and quartz.

Complexes [Cu(vinylsilane)(μ-O2CC2F5)]n can be the source of the volatile derivative [Cu2(O2CC2F5)2], which can be transported in the CVD process and decomposed forming copper materials.Figure optionsDownload as PowerPoint slide