SECONDARY PARTICLE MASS SPECTROMETER

摘要

PURPOSE:To improve ionization efficiency by passing sputtered atoms or molecules through a photoionizing chamber coated with a material having high reflectivity of light on the inside wall. CONSTITUTION:The sputtered atoms or molecules 5 released from an analyzing sample 4 by the bombardment of a high-speed ion beam 2 are made incident on the photoionizing chamber 21 where the atoms or molecules are ionized. The atoms or molecules enter a mass spectrometer 9. The photoionizing chamber 21 has an incident hole for the sputtered atoms or molecules 5, an exit hole for the ions 8 and an incident hole for the light beam 7. The inside wall of the photoionizing chamber 21 is coated with the material which reflects the incident light beam 7 thoroughly. The inside wall of the photoionizing chamber 21 is formed as the paraboloid of revolution and the light is made incident on such paraboloid of revolution coaxially and parallel therewith in the above- mentioned manner. On the other hand, the sputtered atoms or molecules are made to pass the focus of the paraboloid of revolution, then the atoms or molecules are efficiently ionized.