An N‐Heterocyclic Carbene Based Silver Precursor for Plasma‐Enhanced Spatial Atomic Layer Deposition of Silver Thin Films at Atmospheric Pressure

Abstract

Abstract A new N‐heterocyclic carbene (NHC)‐based silver amide compound, 1,3‐di‐ tert ‐butyl‐imidazolin‐2‐ylidene silver(I) 1,1,1‐trimethyl‐ N ‐(trimethylsilyl)silanaminide [(NHC)Ag(hmds)] was synthesized and analyzed by single‐crystal X‐ray diffraction, 1 H and 13 C NMR spectroscopy, as well as EI mass spectrometry, and subsequently evaluated for its thermal characteristics. This new halogen‐ and phosphine‐free Ag atomic layer deposition (ALD) precursor was tested successfully for silver thin film growth in atmospheric pressure plasma enhanced spatial (APP‐ALD). High‐purity conductive Ag thin films with a low sheet resistance of 0.9 Ω/sq (resistivity: 10 −5 Ωcm) were deposited at 100 °C and characterized by X‐ray photoelectron spectroscopy, scanning electron microscopy, optical transmittance, and Rutherford back‐scattering techniques. The carbene‐based Ag precursor and the new APP‐ALD process are significant developments in the field of precursor chemistry as well as metal ALD processing.