Method and device for detecting F atomic concentration

Abstract

The invention relates to a detection method and a detection device for the F atom concentration, wherein, a titration HP absorption spectroscopy is adopted for measuring the F atom concentration; a route selection electric excited continuous wave HP laser is adopted to be a probe light source; the absorption spectrum intensity of HF molecules in a flow field is measured through an infrared window.Because the concentration of F atoms which are dissociated by a system to be detected is certain, when the flow rate of infused hydrogen is increased gradually, the concentration of HF molecules generated can be increased along with the increase of the flow rate until all the F atoms are reacted completely, and the absorption spectrum intensity A of the HF molecules can also be increased gradually to a stable vale; when A is just a maximum value, the corresponding hydrogen flow rate is equal to the F atom concentration. Moreover, the F atom concentration can be directly calculated through theabsorption spectrum intensity of the HF molecules after related parameters are obtained by fitting of data which is obtained by titration processes for many times. The invention is a detection methodand a detection device for the F atom concentration with simple and convenient operation, simple and compact structure, low cost, high measuring precision and good stability.

Description

technical field [0001] The present invention mainly relates to the detection field of F atoms, in particular to a detection method and a detection device of F atom concentration, and is especially suitable for the diagnosis of electro-excited HF / DF chemical lasers, all-gas-phase oxygen-iodine chemical lasers, and the engraving of F-containing plasmas. Etching processing silicon-containing semiconductor field. Background technique [0002] For electrically excited HF / DF lasers and all-gas-phase oxygen-iodine chemical lasers, the yield and yield of F atoms are the most important performance indicators of the core device - the discharge tube, and the direct decisive factor for the power and efficiency of the laser. F atom online detection technology is very important for The improvement and optimization of the laser is of great significance. In the field of semiconductor etching processing, in order to improve the processing efficiency and effect, the research on how to effici...

AI Technical Summary

Problems solved by technology

Its disadvantages are: ① The value of the ratio coefficient K needs to be obtained indirectly through theoretical estimation or other measurement methods

③Since the radiation spectrum is generally weak and located in the visible light band, the signal-to-noise ratio of the signal is very low, requiring signal processing

The disadvantages of this method are: ① The conversion coefficient needs to be determined according to the different samples, and the value of the ionization cross-sectional area is also difficult to obtain

②The mass spectrometer to be used is a precision instrument, its price is very high, and the related operations are also relatively complicated

③There are many simplified assumptions in theory, and the measurement accuracy cannot be guaranteed

The titration method is simple, operable, and high-precision. It is a very commonly used method in the detection field, but the only disadvantage is that it needs to introduce titration substances, which may cause interference to the measured objects.

And in the titration method suitable for the detection of F atomic concentration, the azide used in the azide method is a colorless and toxic liquid with a strong irritating odor and is volatile under normal temperature and pressure. Timely heating or being hit can cause explosion, so this method has certain danger; Utilize HI as titration gas in I atomic absorption spectrometry, and the price of HI gas is very expensive, and the cost of industrial application is too high

[0010] All in all, due to various reasons such as cost, operability, and precision, the above-mentioned methods are not many that can go out of the laboratory and actually be put into industrial applications.

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