Atomic Layer Deposition of Tin Oxide with Nitric Oxide as an Oxidant Gas

Abstract

Atomic layer deposition (ALD) of tin oxide \((SnO_2)\) thin films was achieved using a cyclic amide of Sn(II) (1,3-bis(1,1-dimethylethyl)-4,5-dimethyl-(4R,5R)-1,3,2-diazastannolidin-2-ylidene) as a tin precursor and nitric oxide (NO) as an oxidant gas. Film properties as a function of growth temperature from \(130-250^{\circ}C\) were studied. Highly conducting \(SnO_2\) films were obtained at \(200-250^{\circ}C\) with the growth per cycle of \(~1.4 \mathring{A}\)/cycle, while insulating films were grown at temperatures lower than \(200^{\circ}C\). Conformal growth of \(SnO_2\) in holes of aspect-ratios up to ~50 : 1 was successfully demonstrated.