| 摘要 |
PURPOSE:To measure the distribution of specific chemical species in plasma in a device utilizing plasma highly accurately, by adding a function which removes noises in laser to a plasma distribution monitoring means. CONSTITUTION:In performing measurement, a shutter 20 is closed in advance, a switch 26 is switched to a memory group 24, and the waveform (b) in a noise part is stored. Then, the shutter 20 is opened, the switch 26 is switched to a memory group 25, and the waveform (a) of a measured fluorescence is stored. The phase relationship between the stored two waveforms (a) and (b) described above is judged by a phase matching device 27. Then digital signals, whose phases are matched, are obtained. The measured result of the fluorescence (c) is computed by a substractor 28 and the result is displayed on a display device 29. the distribution of the specific chemical species in plasma 9 in a plasma utilizing device 8 is measured by the above described way. Thus the obstruction casued by high frequency noises generated by a pulse diode laser 1, which utilizes discharge, can be reduced to 1/10. |
