beta-Ketoiminato-based copper(II) complexes as CVD precursors for copper and copper oxide layer formation

Elaheh Pousaneh, Marcus Korb, Volodymyr Dzhagan, Marcus Weber, Julian Noll, Michael Mehring, Dietrich R. T. Zahn, Stefan. E. Schulz, Heinrich Lang

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


The synthesis of ketoiminato copper(II) complexes [Cu(OCRCHC(CH3)NCH2CH2X)(mu-OAc)](2) (X = NMe2: 4a, R = Me; 4b, R = Ph. X = OMe: 5, R = Me) and [Cu(OCRCHCMeNCH2CH2NEt2)(OAc)] (6, R = Me) from RC(O)CHC(CH3)N(H)CH2CH2X (X = NMe2: 1a, R = Me; 1b, R = Ph. X = NEt2: 1c, R = Me. X = OMe: 2, R = Me) and [Cu(OAc)(2)center dot H2O] (3) is reported. The molecular solid-state structures of 4-6 were determined by single crystal X-ray diffraction studies, showing that 4a, b and 5 are dimers which are set up by two [{Cu(mu-OAc)L}] (L = ketoiminato ligand) units featuring a square-planar Cu2O2 core with a distorted square-pyramidal geometry at Cu(II). In contrast, 6 is monomeric with a tridentate-coordinated OCMeCHCMeNCH2CH2NEt2 ligand and a s-bonded acetate group, thus inducing a square-planar environment around Cu(II). The thermal behavior of all complexes was studied by TG (Thermogravimetry) and DSC (Differential Scanning Calorimetry) under an atmosphere of Ar and O-2. Complex 4b shows the highest first onset temperature at 213 degrees C (under O-2) and 239 degrees C (Ar). PXRD studies confirmed the formation of CuO under an atmosphere of O-2 and Cu/Cu2O under Ar. TG-MS studies, exemplarily carried out with 4a, indicate the elimination of the ketoiminato ligands with detectable fragments such as m/z = 15, 28, 43, 44, 45, and 60 at a temperature above 250 degrees C. Vapor pressure measurements displayed that 5 shows the highest volatility of 3.6 mbar at 70 degrees C (for comparison, 4a, 1.4; 4b, 1.3; 6, 0.4 mbar) and hence 4a and 5 were used as MOCVD precursors for Cu/Cu2O deposition on Si/SiO2 at substrate temperatures of 450 degrees C and 510 degrees C. The deposition experiments were carried out under an atmosphere of nitrogen as well as oxygen. The as-obtained layers were characterized by SEM, EDX, XPS, and PXRD, showing that with oxygen as the reactive gas a mixture of metallic copper and copper(I) oxide without carbon impurities was formed, while under N-2 Cu films with 53-68 mol% C contamination were produced. In a deposition experiment using precursor 5 at 510 degrees C under N-2 a pure copper film was obtained.

Original languageEnglish
Pages (from-to)10002-10016
Number of pages15
JournalDalton Transactions
Issue number30
Publication statusPublished - 14 Aug 2018
Externally publishedYes


Dive into the research topics of 'beta-Ketoiminato-based copper(II) complexes as CVD precursors for copper and copper oxide layer formation'. Together they form a unique fingerprint.

Cite this