GAP FILLING METHOD FOR SEMICONDUCTOR DEVICE

摘要

The present invention relates to a gap filling method for a semiconductor device comprising: a first deposition step of depositing a thin film on a metal wiring pattern formed on a substrate, wherein the thin film is deposited on the pattern at a first deposition rate; a first etching step of reducing an aspect ratio by etching the thin film deposited on the upper part of the pattern at a first etching rate; a second deposition step of depositing a thin film on the pattern having the reduced aspect ratio at a second deposition rate which is greater than the first deposition rate; a second etching step of reducing the aspect ratio further by etching the thin film deposited on the upper part of the pattern at a second etching rate which is greater than the first etching rate; and a third deposition step of depositing a thin film on the pattern at a third deposition rate which is greater than the second deposition rate. The method includes multiple separated steps having different deposition rates and different etching rates, and deposition and etching steps are repeated, wherein the deposition rates and the etching rates gradually increase. By adjusting the deposition rate and the etching rate of a thin film in multiple steps during deposition and etching processes, a gap between patterns can be stably and effectively filled without using a gap filling compound even though the pattern has a high aspect ratio.