摘要:
The present invention provides a method and an apparatus for measuring a light absorption spectra which can remove a noise included in a measurement signal, and achieve a high sensitivity of a laser spectral in a good S/N ratio. According to the present invention, there is provided a method for measuring a light absorption spectra comprising the steps of: (i) conducting a Fourier transform of an absorption spectra measured by using a laser beam source; (ii) disassembling in a Fourier space the Fourier transformed signal into a signal resulted from a periodic vibration component and a signal resulted from a molecular absorption spectra; (iii) removing the Fourier component resulted from said periodic vibration component in a Fourier space; and (iv) conducting an inverse Fourier transform on the signal from which said periodic vibration component is removed, whereby reproducing an absorption spectra in a real space.
摘要:
A process and an apparatus for treating an exhaust gas, in which a raw gas and high-boiling intermediate products contained in the exhaust gas let out from a CVD system employing a silicon-containing gas is brought into contact with a transition metal such as nickel or a silicide of such transition metals to decompose or convert them into stable halides, followed by detoxication treatment of the harmful components contained in the exhaust gas.
摘要:
Provided are a CVD system and a CVD process which can grow excellent compound semiconductor thin films of two or more components having least defects and which enjoy high source gas utilization efficiency and increased productivity. According to the CVD system and the CVD process, at least two kinds of source gases are introduced parallel to the surface of a substrate 11 placed in a reactor 10 to grow a compound semiconductor thin film of two or more components on the surface of the substrate 11. The CVD system contains two separators 18, 19 disposed in the reactor 10 on the upstream side of the substrate mounting section to be parallel to the surface of the substrate 11 so as to define in the reactor three parallel layers of passages consisting of a first passage 20, a second passage 21 and a third passage 22; a first CVD gas introducing pipe 23 communicating to the first passage 20; a second CVD gas introducing pipe 24 communicating to the second passage 21; and a deposition accelerating gas introducing pipe 25 communicating to the third passage 22.
摘要:
A device and method for measuring an impurity in a trace concentration in a gas to be measured by infrared spectroscopic analysis employing a diode laser are provided. In order to carry out analysis with high sensitivity and high accuracy, the gas to be measured is directed into sample cell 5 and placed in a low pressure state by a pump 16. Infrared light from the wavelength region in which strong absorption peaks from the impurity can be obtained are oscillated from the diode laser 1, and a derivative absorption spectrum is measured by passing the infrared rays through sample cell 5 and reference cell 8 which is filled with the impurity alone. The spectrum for the gas to be measured and the spectrum for the impurity alone are compared, and the impurity is identified by confirming a plurality of absorption peaks originating from the impurity. Determination of the impurity is then carried out from absorption intensity of the strongest peak. In the case where molecules of the gaseous impurity form clusters in the gas to be measured, analysis is carried while dissociating the clusters by irradiating light having a photon energy of 0.5 eV or greater. The device and method are particularly suitable for carrying out analysis of trace quantities of impurities present in the gases which are used as materials for semiconductor manufacturing.
摘要:
Disclosed is a dissolved oxygen reducing apparatus which enables supplying a liquid containing very small amounts of dissolved oxygen. The dissolved oxygen reducing apparatus includes a bubbling vessel (24) having a liquid charge inlet (21), a liquid discharge outlet (22) and an inert gas discharge port (23), an inert gas sparger (25) provided within the bubbling vessel (24), and a liquid discharge pipe (26) connected to the liquid discharge outlet (22). The bubbling vessel (24) and the liquid discharge pipe (26) have a coefficient of oxygen permeability of not higher than 10.sup.-9 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.atm at 25.degree. C.
摘要:
Disclosed is a rotation/revolution type vapor phase growth apparatus that can maintain constant flow rates of a purge gas and a raw material gas when a raw material gas introducing direction is set to be the same as a susceptor rotation introducing direction. Inside a hollow drive shaft 12 supporting and rotating a disk-shaped susceptor 13, a raw material gas supply tube 20 is coaxially disposed, and between the hollow drive shaft and the raw material gas supply tube, a purge gas flow path 21 is formed. Additionally, in a purge gas introducing nozzle introducing a purge gas in an outer circumferential direction of a flow channel 18 from the purge gas flow path, a gas introducing path 19c is formed in a direction parallel to an upper surface of the susceptor in such a manner as to make a vertical dimension of the gas introducing path constant.
摘要:
The present invention provides a spectroscopic method for analyzing isotopes which makes it possible to simplify a system for measurement and to identify isotopes with high accuracy and sensitivity and to carry out quantitative analysis. The spectroscopic method for analyzing isotopes uses a semiconductor laser beam having as a wavelength zone a 2000 nm-wavelength band as a beam source of wavelengths of the absorption spectra of the isotopes. A reference gas is used for identification of the isotopes where the gas contains collating components having two wavelengths (W1, W2) of well-known absorption spectra in wavelength bands close to the wavelengths (w1, w2) of the absorption spectra of the isotopes.
摘要:
The present invention provides a spectroscopic method for analysing objects in a gas comprising a main ingredient and the objects, both of which the absorption spectra exist in the same wavelength range, with high precision and sensitivity by using a compact and simple single cell system. In accordance with an aspect of the present invention, there is disclosed a spectroscopic method for analysing objects in a sample gas using a laser beam comprising: i) a step of splitting a laser beam into a first laser beam and a second laser beam; ii) a step of transmitting said first laser beam into a sample cell where a sample gas is introduced, and measuring an intensity of a spectrum of said transmitted first laser beam; iii) a step, being performed while performing said step ii), of transmitting said second laser beam into a reference cell where a reference gas is introduced, and measuring an intensity of a spectrum of said transmitted second laser beam, wherein said reference gas comprises an ingredient having at least two spectral lines of which wavelengths in an absorption spectrum of said reference gas are already known; and iv) a step of identifying a wavelength of objects to be measured in said sample gas by comparing said spectrum of sample gas with said spectrum of reference gas using said at least two spectral lines of said reference gas as reference wavelengths.
摘要:
The present invention relates to a device and method for measuring an impurity in a trace concentration in a gas to be measured by means of infrared spectroscopic analysis employing a diode laser. In order to carry out analysis with high sensitivity and high accuracy, the gas to be measured is directed into sample cell 5 and placed in a low pressure state by means of pump 16. Infrared light from the wavelength region in which strong absorption peaks from the impurity can be obtained are oscillated from the diode laser 1, and a derivative absorption spectrum is measured by passing the infrared rays through sample cell 5 and reference cell 8 which is filled with the impurity alone. The spectrum for the gas to be measured and the spectrum for the impurity alone are compared, and the impurity is identified by confirming a plurality of absorption peaks originating from the impurity. Determination of the impurity is then carried out from absorption intensity of the strongest peak. In the case where molecules of the gaseous impurity form clusters in the gas to be measured, analysis is carried while dissociating the clusters by irradiating light having a photon energy of 0.5 eV or greater. The present invention is particularly suitable for carrying out analysis of trace quantities of impurities present in the gases which are used as materials for semiconductor manufacturing.