Miniaturization of electronic devices imposes challenges in terms of materials and production methods, and advances in the chemical vapor deposition (CVD) of metals are a key prerequisite toward reliable interconnects that are essential for their functionality. Electrically conducting ultrathin films of pure copper were grown on glass and silicon substrates starting at a temperature of 195 degrees C. The growth kinetics does not exhibit any measurable nucleation time enabling early stage coalescence and high electrical conductivity. In situ monitoring of the CVD process using synchrotron-based mass spectrometry shows that the enhanced dehydrogenation of alcohols by copper(II) acetylacetonate precursor drives the Cu-0 deposition, which is kinetically favorable already at low temperature. (C) 2009 The Electrochemical Society. [DOI: 10.1149/1.3205478] All rights reserved.