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

摘要

To gain spatially resolved spectroscopic information a photo-emission electron microscope (PEEM)l equipped with an energy analyser (μESCA) 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/μESCA 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 precipitions seen in the PEEM were investigated using μ NEXAFS together with μPES. A model is proposed that is able to describe the photoemission process from silicon together with its native oxide using Hg-lamp illuminaiton (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.