Characteristics of carbon-containing low-k dielectric SiCN thin films deposited via remote plasma atomic layer deposition

This study investigates amorphous SiCN thin films deposited by remote plasma atomic layer deposition. Bis[(diethylamino)dimethylsilyl](trimethylsilyl)amine (DTDN-2) and N₂ plasma were used as the precursor and reactant, respectively. The deposition temperature ranged from 100 to 300 °C, and the plasma power was set to 100 and 300 W. It was determined that the SiCN film carbon content increased with decreasing plasma power and deposition temperature. Likewise, decreasing the plasma power and deposition temperature lowered the dielectric constant of the film owing to the low film density and high carbon content. It was found that the composition of the SiCN film deposited at 300 °C was similar to that of the SiN film. The wet etch rate of the film deposited at 200 °C had the lowest value owing to the carbon content and high film density. The chemical bonding states of Si, C, and N were measured by x-ray photoelectron spectroscopy.