Me 3SiC [tbnd]C–CMe [dbnd]CH 2 copper(I) β-diketonates: Synthesis, solid state structure, and low-temperature chemical vapour deposition

Abstract

The ene-yne copper(I) β-diketonates [(η 2-TMSMB)Cu(β-diketonate)] (β-diketonate = ac etyl ac etonate/acac, 5; = 1,3- d i-tert- b utyl ac etonate/dbac, 6; = 1,1,1,5,5,5- h exa f luoroacetyl ac etonate/hfac, 7; TMSMB = 4- T ri M ethyl S ilyl-2- M ethyl- B ut-1-ene-3-yne, Me 3SiC C–CMe CH 2) are accessible by the reaction of [(η 2-TMSMB)Cu(μ-Cl)] 2 ( 3) with [Na(β-diketonate)] (β-diketonate = acac, 4a; = dbac, 4b; = hfac, 4c) in a 1:2 molar ratio. Complexes 6 and 7 are also formed, when Cu 2O ( 8) is reacted with H-hfac ( 9a) or H-dbac ( 9b), respectively. The solid state structure of 7 is reported. The copper(I) ion possesses a planar environment caused by the η 2-coordinated TMSMB ligand and the chelate-bound hfac group, while the CMe CH 2 entity stays free. The thermal properties of 5– 7 were determined by applying T hermo G ravimetry (TG) and D ifferential S canning C alorimetry (DSC). All complexes decompose in a two-step process beginning at ca. 85 °C. Elimination of TMSMB produces [Cu(β-diketonate)] which disproportionates to give [Cu(β-diketonate) 2] and elemental copper. Preliminary hot-wall C hemical V apour D eposition experiments (CVD) were carried out with 7. Copper films were deposited onto TiN-coated oxidised silicon wafers at a precursor vaporisation temperature of 50 °C and a deposition temperature of 145 °C. The films were characterised by SEM and EDX.