A spectro-microscopic approach for spatially resolved characterisation of semiconductor structures in PEEM

To gain spatially resolved spectroscopic information a photo-emission electron microscope (PEEM) equipped with an energy analyser (mu ESCA) is used in combination with synchrotron radiation. With this equipment it is possible to obtain near edge absorption as well as photoelectron spectra. We demonstrate the ability of the PEEM/mu ESCA to measure high resolution photoelectron spectra. We have used this technique to investigate grains and grain boundaries on multicrystalline silicon without removing the native oxide. The various precipitations seen in the PEEM were investigated using mu NEXAFS together with mu PES. A model is proposed that is able to describe the photoemission process from silicon together with its native oxide using Hg-lamp illumination (hv(max) = 4.9 eV). This novel model and the approach of investigating local inhomogeneities are designed to study the lateral doping distribution of industrial silicon devices as well as to observe the dopant diffusion under realistic conditions. We expect that the availability of highly brilliant light sources such as the new undulator beamline at BESSY-II will be highly beneficial for such investigations. (C) 2000 Elsevier Science Ltd. All rights reserved.