2010 Volume 51 Issue 2 Pages 231-236
We have constructed a cathodoluminescence (CL) detection system that records the CL spectra emitted from each point raster-scanned by the incident electron probe in a conventional scanning electron microscope. The CL spectrum is detected by a 32 channel high-speed high-sensitive photoelectron multiplier array set behind the spectrometer. The shortest signal sampling time is 8 s for a frame of 512×512 pixels and all the imaging and spectroscopic signals are stored in two 8-megabyte files. Maximum image size is 2048×2048 pixels. The microscope displays a spectral accurate full color (whole spectrum) CL image, twenty-nine monochromic images and the spectrum of each pixel point in the corresponding secondary electron image. The spatial resolution of CL image reaches 25 nm by reducing the quantum noise and the phosphorescent delay effect using a slow signal sampling time of 40 s with a 6-keV incident electron probe. Some examples are demonstrated using SnO2-doped ZnO-Ba2O3 ceramics and photosensitive cyanine dyes.