FILM THICKNESS MEASUREMENT DEVICE AND FILM THICKNESS MEASUREMENT METHOD

PROBLEM TO BE SOLVED: To provide a film thickness measurement device capable of measuring the film thickness accurately and certainly.SOLUTION: The film thickness measurement device includes: a terahertz wave generator 19 for generating a terahertz wave; a prism 21 including an incidence plane 69 for receiving the terahertz wave emitted from the terahertz wave generator, an abutting surface 70 capable of abutting on the surface of a sample 3 including a first film 31a on the first film side, and an outgoing surface 71 through which the reflected wave from the sample is output; a terahertz wave detector 23 for detecting each of the S polarization component and P polarization component of the reflected wave output through the outgoing surface of the prism; and a control unit 6 for determining the thickness of the first film formed on the sample on the basis of the difference between the time waveform of the S polarization component and that of the P polarization component.SELECTED DRAWING: Figure 1 【課題】より正確かつ確実に膜厚を測定し得る膜厚測定装置を提供する。【解決手段】テラヘルツ波を発生させるテラヘルツ波発生器１９と、テラヘルツ波発生器から出射されるテラヘルツ波が入射される入射面６９と、第１の膜３１ａを含む試料３の第１の膜が形成されている側の面に当接可能な当接面７０と、試料からの反射波が出射される出射面７１とを有するプリズム２１と、プリズムの出射面から出射される反射波のＳ偏光成分とＰ偏光成分とをそれぞれ検出するテラヘルツ波検出器２３と、Ｓ偏光成分の時間波形とＰ偏光成分の時間波形との差に基づいて、試料に形成された第１の膜の膜厚を判定する制御部６とを有している。【選択図】図１