Development of Multi-purpose Spectroscopy System

Photo-Luminescence (PL) and Cathode-Luminescence (CL) apparatus were designed and created for measurements of fluorescent light from many kinds of semiconductors and other various high-functional materials. A 375-nm wavelength ultra-violet laser beam focused in ～5 pm diameter at a target surface is used for stimulating target materials in PL measurement. A well-collimated electron beam of several micro amperes at maximum energy of 30-keV is used for stimulating target materials in CL measurement. Luminescences between 200 DM-950 nm wavelengths are introduced into a single crystal Ge detector via the light-fiber. One photon produces one electron via the photoelectric effect in Ge crystal. Thus, according to the number of incident photons, the same number of electrons is produced and emitted from Ge crystal and introduced into a photo-multiplier, which amplifies these electron numbers by about one million. These amplified electrons are introduced into a high- sensitivity current meter. Thus, luminescence intensity is proportional to current intensity. Even one photon can be detected by this analysis system. We successfully observed luminescence from fluorescent oil painted on the Si substrate and luminescence from the GaAs semiconductor substrate