Non-invasive electrical characterization of semiconductor interfaces

The semiconductor–insulator interface is very critical for the operation of various devices. The time-resolved microwave conductivity (TRMC) is an efficient tool for non-invasive characterizations during the growth of semiconductors and interfaces. TRMC measures the transient microwave reflectivity induced by UV laser-photogenerated carriers. The analysis of the signal (amplitude and shape) as a function of carrier density enables to separate between bulk and interface recombination, and to estimate surface state density, surface recombination velocity, and the effect of interface electric field. The experiment is numerically modeled. The measurements are achieved for interfaces such as c-Si/SiO2, c-Si/Si3N4, and μc-Si/Si3N4, and are correlated with capacitance measurements as well as with model simulation.