Nanocluster deposition for oxide thin film growth at near room temperature.

Metal-organic chemical vapor deposition (MOCVD) at near room temperature would not only enable integration of oxide films on polymers but would provide the capability of conformal coating of high-aspect ratio features required for fabrication of many micro-and nanoelectronic devices. The concept of near room temperature MOCVD (nanocluster deposition: NCD) consists of the production of a single phase with nanosized crystalline nuclei by a chemical vapor reaction at the showerhead maintained above the decomposition temperature of the precursors and consequently deposition of the nanosized crystalline films on unheated substrates. Deposition of the nanosized crystalline nuclei on unheated substrates was performed by controlling both the showerhead temperature and the working pressure. The Bi(3)NbO(7) (BNO) films deposited without substrate heating (real temperature of substrate surface: 50 °C) exhibit a crystalline single phase with smooth and dense morphologies, a dielectric constant of 30, a leakage current density of ∼10(-6) A cm(-2) at 0.3 MV cm(-1) and a step coverage of approximately 93% for films deposited at 100 °C on high-aspect ratio features. An NCD provides a new platform for near room temperature deposition of oxide thin films, opening the way for film deposition on polymer substrates to enable a flexible electronic device technology.