Characterization of periodically delta-doped semiconductors by capacitance-voltage profiling

The capacitance-voltage (C-V) profiles of periodically Si-delta-doped InP samples were measured, and these are described by a succession of equally spaced peaks, with a spatial periodicity which closely matches the intended doping period. Theoretical C-V spectra for periodically Si-delta-doped semiconductors were calculated. Analysis of the data indicates that the spacing between the peaks seen in the experimental C-V spectrum is a reliable measure of the true doping period of the sample. The C-V spectrum of the periodically delta-doped semiconductor is well approximated by a linear combination of C-V curves for isolated delta-doped layers located at successive positions of analogous layers in the periodically delta-doped sample. The practical limitations of the C-V technique when applied to periodically delta-doped semiconductors are discussed.