Quantitative Measurement of Mass Spectra with Quadrupole Mass Filter-Sputter Ion Pump System

Autor: Masao Hashiba, Toshiro Yamashina, Takao Hanasaka
Rok vydání: 1974
Předmět:
Zdroj: SHINKU. 17:186-193
ISSN: 1880-9413
0559-8516
DOI: 10.3131/jvsj.17.186
Popis: Reproducibility and stability in pattern coefficient of a quadrupole mass filter in a sputter ion pump system have been studied systematically. In order to the quantitative measurement of dynamic re-emitted gases from the ion pump, a conductance adjusting valve was inserted between the measuring chamber and ion pump. Before admission of gases, most of residual gases such as hydrogen, nitrogen and some hydrocarbons were observed not to increase with increase of total pressure by closing the adjusting valve, while argon and methane were increased. When propylene was admitted into the chamber as sample gas, the minimization of the re-emission of gases was achieved in case of 5-10 as the pressure ratio between the chamber and pump in this study. Although the re-emission from the pump reduce for larger pressure ratio, the dynamic re-emission from the chamber increased considerably as closing the valve, in spite of the relatively small amount of residual gases as seen in the case before gas admission.Comparison of the reproducibility in pattern coefficient of the mass filter with and without electron multiplier was also investigated systematically. The fluctuation coefficient 2σ/x (σ : standard deviation, x : mean value of pattern coefficient) was approximately 2 percent and no troublesome effect by the multiplier was found in the quantitative analysis within the period of three days.
Databáze: OpenAIRE