Publisher : Institude of Korean Electrical and Electronics Engineers
DOI : 10.7471/ikeee.2015.19.4.541
Title & Authors
Endpoint Detection Using Both By-product and Etchant Gas in Plasma Etching Process Kim, Dong-Il; Park, Young-Kook; Han, Seung-Soo;
In current semiconductor manufacturing, as the feature size of integrated circuit (IC) devices continuously shrinks, detecting endpoint in plasma etching process is more difficult than before. For endpoint detection, various kinds of sensors are installed in semiconductor manufacturing equipments, and sensor data are gathered with predefined sampling rate. Generally, detecting endpoint is performed using OES data of by-product. In this study, OES data of both by-product and etchant gas are used to improve reliability of endpoint detection. For the OES data pre-processing, a combination of Signal to Noise Ratio (SNR) and Principal Component Analysis (PCA),are used. Polynomial Regression and Expanded Hidden Markov model (eHMM) technique are applied to pre-processed OES data to detect endpoint.