Controllability of gap‐filling for intermetal SiO2 deposition by biased helicon plasma chemical vapor deposition

Abstract

AbstractThe gap between patterned aluminum was filled with SiO2 formed by the reaction of SiH4‐O2 gas using helicon plasma and a biased substrate. The relationship between the SiO2 deposition rate and plasma source power was investigated.It was found that the SiO2 deposition rate was dependent on the rate of SiH4 supply and was independent of the plasma source power. The sputtering rate due to biasing the substrate decreased with increase of the plasma source power. It was found also that the sputtering rate at which void generation is suppressed could be controlled not only by the bias power but also by the plasma source power. Even when the plasma source power and bias power were set at a low level, a sufficient sputtering rate was obtained. The gap‐filling rate (the net deposition rate) was determined by the difference between the raw deposition rate determined by SiH4 supply and the sputtering rate and could be controlled by the plasma source power.