Determination of band offsets in a-Si:H/c-Si heterojunctions from capacitance–voltage measurements: Capabilities and limits

• Published in: Thin solid films 2007-07, Vol.515 (19), p.7481-7485
• Main Authors: Gudovskikh, A.S., Ibrahim, S., Kleider, J.-P., Damon-Lacoste, J., Roca i Cabarrocas, P., Veschetti, Y., Ribeyron, P.-J.
• Format: Article
• Language: English
• Subjects: Applied sciences; Capacitance technique; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Defects and impurities: doping, implantation, distribution, concentration, etc; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Energy; Exact sciences and technology; Heterostructures; Natural energy; Photovoltaic conversion; Physics; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy; Surface and interface electron states; Surface states, band structure, electron density of states; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2006.11.198

The capabilities and limitations of the well-known C– V technique for the determination of the conduction band offsets in (n)a-Si:H/(p)c-Si heterojunctions are presented. In particular, the effects due to the presence of an inversion layer in c-Si and a non-negligible defect density at the a-Si:H/c-Si interface on the reliability of the C– V intercept method are discussed. The influence of the Fermi level positions in (p)c-Si and (n)a-Si:H on the inversion layer formation and the influence of the interface defect density have been analysed using numerical simulations and experimental measurements.