MIXTURE GAS MONITORING SYSTEM IN SEMICONDUCTOR FABRICATING PROCESS AND CONTROLLING METHOD THEREOF

摘要

PURPOSE: A mixture gas monitoring system in a semiconductor fabricating process is provided to monitor the composition of mixture gas flowing to a process chamber by installing a monitoring system using Fourier transform-infrared spectrometry(FT-IR) in a portion where a source gas is introduced to the inside of the process chamber. CONSTITUTION: A gas supply system(10) supplies the mixture gas from a plurality of source gases according to a proper composition ratio. The mixture gas monitoring system is installed between the gas supply system and the process chamber(40) using the mixture gas. An IR light source unit outputs IR laser, installed in a gas supply path between the gas supply system and the process chamber. An IR detecting unit receives the IR laser from the IR light source unit and outputs the detection information regarding the mixture gas supplied from the gas supply system. A monitoring apparatus(20) receives the detection information from the IR detecting unit determines the composition ratio of the mixture gas by using the detection information. If the composition ratio of the mixture gas in the process chamber is not proper, the monitoring apparatus readjusts the composition ratio of the mixture gas and supplies the mixture gas of the readjusted composition ratio to the gas supply system.