Revision of interface coupling in ultra-thin body silicon-on-insulator MOSFETs

• Published in: Semiconductor Physics Quantum Electronics & Optoelectronics
• Date: 2013
• Main Authors: Rudenko, T., Nazarov, A., Kilchytska, V., Flandre, D., Popov, V., Ilnitsky, M., Lysenko, V.
• Format: Article
• Language: English
• Published: Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України 2013
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/117737
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Revision of interface coupling in ultra-thin body silicon-on-insulator MOSFETs / T. Rudenko, A. Nazarov, V. Kilchytska, D. Flandre, V. Popov, M. Ilnitsky, and V. Lysenko // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2013. — Т. 16, № 3. — С. 300-309. — Бібліогр.: 23 назв. — англ.

The charge coupling between the gate and substrate is a fundamental property of any fully-depleted silicon-on-insulator (SOI) MOS transistor, which manifests itself as a dependence of electrical characteristics at one Si film/dielectric interface on charges at the opposite interface and opposite gate bias. Traditionally, gate-to-substrate coupling in SOI MOS transistors is described by the classical Lim-Fossum model. However, in the case of SOI MOS transistors with ultra-thin silicon bodies, significant deviations from this model are observed. In this paper, the behavior of gate coupling in SOI MOS structures with ultra-thin silicon films and ultra-thin gate dielectrics is studied and analyzed using experimental data and one-dimensional numerical simulations in classical and quantum-mechanical modes. It is shown that in these advanced transistor structures, coupling characteristics (dependences of the front- and back-gate threshold voltages on the opposite gate bias) feature a larger slope and much wider (more than doubled) linear region than that predicted by the Lim-Fossum model. These differences originate from both electrostatic and quantization effects. A simple analytical model taking into account these effects and being in good agreement with numerical simulations and experimental results is proposed.