Room-temperature deposition of highly-insulating SiOCH films by plasma-enhanced chemical vapor deposition using tetraethoxysilane

Highly-insulating silicon oxide which contained hydrocarbon (CHn) groups (SiOCH) was deposited at room temperature by plasma-enhanced chemical vapor deposition using tetraethoxysilane. The carbon-rich SiOCH film deposited at 50W, 27 °C showed the high resistivity of 6 × 1015Ω cm at 0.5MV/cm. The insulating properties strongly depended on the deposition temperature and radio frequency (RF) power. The SiOCH films deposited at 300W, 53 °C showed the low carbon content and low resistivity due to the incorporation of hydroxyl (OH) groups generating electron traps. The room-temperature deposition at low RF power enabled the high-CHn addition, resulting in the suppression of OH incorporation into the films. The highly-insulating properties of the room-temperature deposited SiOCH originated from the suppression of OH incorporation.