Description:
We present a new technique for imaging p–n junctions in semiconductors based on Auger electron spectroscopy. By measuring fine Auger electron spectra of the semiconductor material (e.g., silicon LVV Auger), the position of the Fermi level in the band gap of the semiconductor is estimated from the energy shift of the Auger spectra. The position of the Fermi level depends on the type of dopant. By applying a correlation calculation to measure the Auger energy shift, which is smaller than the band gap of the semiconductor, we can successfully image two-dimensional p–n junctions in LSI devices.