Single defects and noise in sub-u MOSFETs

摘要

The capture and emission of electrons and holes into and from single, individual interface traps are studied in micron-sized MOSFETs. The trapping process creates discrete switching in the source-drain resistance, which is observed as a random telegraph signal in the source-drain current. The number of traps may be counted in quantized transients observed after pulsed filling of traps. The average rate time constants for the trapping process are consistent with Coulomb repulsive centers, i.e. acceptors near the conduction band edge and donors near the valence band edge of silicon. The capture and emission rates are strongly activated by an interfacial barrier. The 1/f noise power spectrum is quantitatively described by the random telegraph signal of several interface traps. Individual traps induce Fermi level pinning in the 2D SiO$-2$/-Si system.