Plasma process apparatus with in situ monitoring, monitoring method, and in situ residue cleaning

摘要

A plasma process apparatus having a plasma chamber with in situ monitoring, a monitoring method, and a method for in situ cleaning a plasma chamber. The apparatus includes a sampling manifold which induces flow of a sample gas from a plasma chamber through the manifold. A gas analyzer analyzes the sample gas flowing through the sampling manifold. The in situ monitoring method monitors an initial gas to establish background levels, and bakes the apparatus to reduce contaminants, if necessary. The monitoring method then monitors a process reaction and, after unloading a wafer and discharging a waste gas, monitors an in situ cleaning reaction. Monitoring involves inducing flow of a gas from the plasma chamber through the sampling manifold, and then analyzing the gas in the manifold with a gas analyzer. The cleaning method includes using a mixture of sulfur hexafluoride and chlorine to clean the plasma chamber after etching a polysilicon layer.