High-Quality Low-Temperature Silicon Oxide by Plasma-Enhanced Atomic Layer Deposition Using a Metal–Organic Silicon Precursor and Oxygen Radical

Recently, SiO₂ grown at low temperatures has been highlighted for a range of applications. In this letter, SiO₂ films were deposited at 280°C by plasma-enhanced atomic layer deposition (ALD) using bis-diethylamino-silane and O₂ plasma. The electrical conduction mechanisms of a 38-nm-thick SiO₂ film were found to be ohmic and Fowler-Nordheim tunneling in the low- and high-voltage ranges, respectively. The electrical breakdown field of the silicon oxide films was measured at ~10 MV/cm. The excellent breakdown field was well explained by the fact that ALD SiO₂ has very low carbon content (<; 0.5%) and does not have any oxygen deficiency and nonbridging oxygen. Compared to wet SiO₂, the increase in etch rates was attributed to the existence of strained bonds.