In-situ quantification of deposition amount in a poly-Si etch chamber using optical emission spectroscopy of etching plasmas

Aiming at quantification of deposition amount in a ploy-Si etch chamber in-situ, we performed optical emission spectroscopy of a gate ploy-Si etching plasma. We obtained relative quantity of deposition in the etch chamber from the ratio of optical emission intensity of SiBr to He in the plasma. Based on the results of relative quantity of deposition depending on cumulative etched wafers in the chamber, we estimated a mechanism of particle occurrence from the deposition in the chamber.