Electrical properties of fully depleted silicon-on-insulator wafers

Fully depleted silicon on insulator (FDSOI) substrates are playing a key role in the development of next-generation integrated circuits, paving the way for future electronic technologies. In the characterization of FDSOI wafers with a 12 nm thick silicon film and a 25 nm buried oxide (BOX) film, capacitance and conductance measurements have revealed a novel polarization propagation effect. This effect, which occurs under high bias voltages, significantly alters the electrical properties of FDSOI substrates and can be effectively modeled by an RC transmission line. The measurements also reveal the high sensitivity of FDSOI substrates to various external factors, such as frequency, excitation signal amplitude, light exposure, and oxide gate thickness. The addition of an oxide gate on FDSOI structures also induces quantum confinement effects in the silicon film, significantly modifying the electrical characteristics of the devices. This study, which is of interest to both academic research and industry, constitutes a major scientific contribution to the understanding and characterization of next-generation FDSOI substrates.