Metallic Copper Thin Films Grown by Plasma‐Enhanced Atomic Layer Deposition of Air Stable Precursors

Abstract

The authors, report here on the deposition of metallic copper thin films by plasma‐assisted atomic layer deposition (ALD) with an air stable and volatile precursor − [Cu((Py)CHCOCF3)2]2 (Py = pyridine) − that stands out due to its facile synthesis and easy handling under ambient conditions. Copper thin films are obtained by decomposing [Cu((Py)CHCOCF3)2]2 in hydrogen plasma in a concomitant deposition and recrystallization process. The thermal stability of the precursor prevents thermally induced decomposition, which allows precise control over thickness and film homogeneity. Electrical measurements of the as‐deposited samples show clear interdependence of sheet resistance on the substrates surface roughness, thereby, films with higher roughness show higher resistance. Combined X‐Ray photoelectron spectroscopy of Cu 2p peak and Cu LMM peak, as well as resistivity values of 58 Ω □−1 confirm the high quality of copper films without the need of further annealing steps under reducing atmosphere.