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A comparative study of the growth behavior of nm-thin ruthenium layers by plasma enhanced atomic layer deposition using two ruthenium precursors is discussed. For bis(ethylcyclopentadienyl)-ruthenium or Ru(EtCp)2, we have found a large incubation time on titanium nitride when using N2/NH3 plasma. With N2/H2 plasma the incubation was significantly reduced. For (methylcyclopentadienyl-pyrrolyl)ruthenium or MCPRu, no incubation was observed for either plasmas. The measured growth per cycle was ~ 0.02 nm for Ru(EtCp)2 whereas ~ 0.04 nm for MCPRu. The top surface of the PE-ALD Ru films can be oxidized without surface roughening by applying a low pressure O2 anneal, while O3 exposure leads to roughening due to etching and re-deposition downstream of etched Ru. Awareness of the impact of oxidizing ambients on Ru is essential for successful integration of Ru layers as electrode in metal-insulator-metal capacitors.

In this paper we compare a novel plasma-enhanced atomic layer deposition (PEALD) oxide with more conventional HTO and ISSG oxides. We show that, remarkably for a deposited oxide, the oxide quality is, both in terms of field-to-breakdown and SILC generation, comparable to that of ISSG thermal oxide. Finally, we show that data retention of SONOS stack with PEALD is significantly better than for stacks with ISSG tunnel oxide. PEALD oxide is, therefore, a promising choice for 3D non-volatile flash technologies.