Simultaneous measurement of CH4 concentration and temperature distributions in a semiconductor process chamber

Methane (CH4) concentration and temperature distributions were measured in a semiconductor process chamber using computed tomography-tunable diode laser spectroscopy (CT-TDLAS). A semiconductor chamber was designed with 32 laser-paths to collect the infrared spectrum of CH4 with tunable diode laser absorption spectroscopy. Absorptions at wavelength of 1628.1 nm and 1653.7 nm were used to reconstruct CH4 concentration and temperature...