Abstract
Silicon nitride films were deposited in SiH4–NH3–N2 plasma at room temperature by using a plasma-enhanced chemical vapor deposition system. SiN film characteristics examined as a function of radio frequency bias power include a deposition rate, a refractive index, and a surface roughness. Ion energy diagnostics was also conducted to analyze in detail the bias power effect. An increase in ion energy and a decrease in ion energy flux were observed with increasing the bias power. Several relationships between ion energy variables and film properties were identified. For all the variations in the bias power, the deposition rate, the refractive index, and the surface roughness varied in the range of 185–532 Å/min, 1.89–2.48, and 0.24–0.96 nm, respectively. Very high refractive index could be achieved by controlling the bias power.
