Infrared absorption measurement method, infrared absorption measurement device, and method of manufacturing semiconductor device

摘要

An infrared absorption measurement method including: (a) measuring infrared absorption of a target component in a sample gas while decompressing the sample gas so that an absorption area in a peak region of the target component in the infrared absorption shown in a graph is within a predetermined range, the graph showing the relationship between the wave number and absorbance of the sample gas; and (b) calculating the concentration of the target component in the sample gas based on the absorption area and pressure of the decompressed sample gas.