Electrical characterization of a single-crystalline Si quantum well formed by thermal oxidation of ultrathin silicon-on-insulator film (Al/SiO2:c-Si QW/n-Si) for optoelectronic applications.

The incorporation of nanostructures such as silicon nanocrystals into the oxide of an MOS structure has attracted significant interest in improving the performance of MOS-based devices. However, integrating crystalline silicon quantum wells into this structure remains a challenge due to the difficulties associated with growing a crystalline Si film on an amorphous oxide. This study presents the fabrication and electrical characterization of a quantum well formed by the thermal oxidation of an ultrathin silicon-on-insulator (UT-SOI) film. Structural analysis by electronic transmission reveals the formation of a monocrystalline quantum well with a homogeneous thickness and a perfectly flat surface, free from any crystalline defect. The electrical characterizations, carried out using capacitance–voltage (C–V) and current–voltage (I–V) measurements, confirm the success of the integration of the quantum well into the MOS structure. In addition, a systematic study of the dielectric properties details the evolution in bias voltage and in frequency of the main dielectric parameters of the structure such as the dielectric constant (ε*), the electrical loss (Tan δ), and the electrical modulus (M*). The results obtained demonstrate normal operation of the new structure, paving the way for efficient integration of this type of nanostructures in MOS-based photodetectors and solar cells. [ABSTRACT FROM AUTHOR]