Decomposition Schemes of Copper(I) <I>N</I>,<I>N</I>′-Diisopropylacetamidinate During Chemical Vapor Deposition of Copper

Abstract

Copper(I) N,N'-diisopropylacetamidinate [Cu(amd)]2 (amd = CH(CH3)2NC(CH3)NCH(CH3)2), an oxygen and halogen-free compound, was previously tested as precursor for pure copper CVD and ALD films. The present work deals with the investigation of the composition and of the reactivity of the gas phase during the CVD process. The work was performed by mass spectrometry as a function of temperature in two different, though complementary environments: (A) in a miniature, low pressure hot wall CVD reactor, (B) in a cold wall reactor operating at subatmospheric pressure. (A) revealed that the onset of thermal decomposition is 140 degrees C and 130 degrees C in vacuum and in the presence of hydrogen, respectively; maximal decomposition degree is reached at temperature higher than 200 degrees C. The protonated ligand H(amd) is the main gaseous decomposition by-product; propene CH2=CHCH3, acetonitryle CH3C[triple bond]N and iminopropane CH3C(CH3)=NH are also observed in vacuum. Heterogeneous decomposition mechanism both in vacuum and hydrogen presence is discussed.

Trends in Copper Precursor Development for CVD and ALD Applications

“…36 This corroborated decomposition work that was under taken at UC-Riverside. 37 These works highlight the fact that the copper amidinate compounds undergo very slow decomposition at 140…”

Development of Volatile Inorganic Compounds and Their Application for Chemical Vapour Deposition of Metal and Metal Oxide Thin Films

“…This same group found that this precursor would decompose at 140°C without hydrogen. [105] This corroborated decomposition work that was under taken at UC-Riverside. [106] These works highlight the fact that the copper amidinate compounds undergo very slow decomposition at 140°C that accelerates when temperatures reach >200°C.…”

“…Copper(I)-N,N'-di-isopropylacetamidinate has been shown to undergo CVD deposition as low as 140°C, [122,125] and produces free amidine, acetonitrile, propene and iminopropane when allowed to thermally decompose in the absence of a reducing agent. [126] These findings have been corroborated in the surface study work of copper(I) acetamidinates on nickel where, above 130°C, the selflimiting nature of the monolayer is compromised and continuous uptake of the copper precursor is observed. Similar ligand fragments were identifed in the surface work as in the gas phase work.…”

Metallization of polymer composites by metalorganic chemical vapor deposition of Cu: Surface functionalization driven films characteristics

“…This is the topic of the present paper. We report on the influence of ex situ and/or in situ treatments of the surface of polymer composites on the morphological characteristics and on the growth rate of Cu films processed by MOCVD from (hfac)Cu(I)(MHY) (Gigacopper®) where (hfac) is hexafluoroacetylacetonate and (MHY) is 2-methyl-1-hexen-3-yne [4][5][6] and from copper(I) N,N′-diisopropylacetamidinate, ([Cu(amd) 2 ]) [7,8]. We investigate six surface pre-treatments, namely (i) mechanical polishing and (ii) chemical etching aiming at the formation of a controlled surface roughness and thus enhancement of mechanical anchoring of the metal, (iii) degasing of the composite aiming at desorption of contaminants, (iv) UV photooxidation in air aiming at the replacement of non-polar C\C and C\H bonds by polar O\C = O ones, (v) flush of the substrate with H 2 O vapors during the first steps of the deposition aiming at the creation of \OH functional groups and at the formation of a metal oxide interphase between the polymer and the pure metal, and finally (vi) the grafting of a thin polydopamine interlayer.…”