  An accurate description of spatial variations in the energy levels of
patterned semiconductor substrates on the micron and sub-micron scale as a
function of local doping is an important technological challenge for the
microelectronics industry. Spatially resolved surface analysis by photoelectron
spectromicroscopy can provide an invaluable contribution thanks to the
relatively non-destructive, quantitative analysis. We present results on highly
doped n and p type patterns on, respectively, p and n type silicon substrates.
Using synchrotron radiation and spherical aberration-corrected energy
filtering, we have obtained a spectroscopic image series at the Si 2p core
level and across the valence band. Local band alignments are extracted,
accounting for doping, band bending and surface photovoltage.
