Effect of plasma power on properties of hydrogenated amorphous silicon carbide hardmask films deposited by PECVD

Abstract We report the effects of plasma power on the properties of hydrogenated amorphous silicon carbide (a-SiC:H) films deposited by plasma enhanced chemical vapor deposition (PECVD). The optical and mechanical properties of the a-SiC:H films deposited with various plasma powers ranging from 100 to 1600 W were investigated. With the increase in the plasma power, both refractive indices and extinct coefficients decrease monotonically; meanwhile, the hardness and elastic modulus as well as the compressive stress are observed to increase. These properties depend primarily on the chemical structure involving different bonding configurations and the concentration of constituent elements with various plasma powers. We demonstrate that the increase in plasma power can induce a decrease in refractive index owing to the enlargement of the Si-C bonds and the carbon content of a-SiC:H films.