Comparative study of NSB and UTB SOI MOSFETs characteristics by extraction of series resistance

• Published in: Solid-state electronics Vol. 91; pp. 28 - 35
• Main Authors: Karsenty, A., Chelly, A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-01-2014; Elsevier
• Subjects: Applied sciences; Channels; Construction; Design. Technologies. Operation analysis. Testing; Devices; Drains; Electron mobility; Electronics; Exact sciences and technology; Gate-to-channel capacitance; Integrated circuits; Microelectronic fabrication (materials and surfaces technology); Mobility extraction; Molecular electronics, nanoelectronics; Nanocomposites; Nanomaterials; Nanostructure; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Series resistance; SIMOX; SOI MOSFET; Transistors; Mobility extraction; SIMOX; Series resistance; Gate-to-channel capacitance; SOI MOSFET; MOSFET; SIMOX technology; Charge carrier mobility; Modeling; Nanoelectronics; Silicon on insulator technology; Microelectronic fabrication; n type semiconductor; Drain current; Electron mobility; Wafer; Electrical characteristic; Ultrathin films; MOS technology; Voltage dependence; Ion implantation; Gate voltage; Integrated circuit; Capacitance; Feature extraction; Comparative study
• ISSN: 0038-1101; 1879-2405
• DOI: 10.1016/j.sse.2013.09.003

•Electrical characteristics of UTB (46nm) and NSB (1.6nm) SOI-MOSFETs are compared.•Initial SOI channel is thinned down to 1.6nm using a recessed-gate process.•Drain current values were found surprisingly different by 3 orders of magnitude.•Such a huge contrast was not found coherent with the literature.•We built a useful model approach to interpret NSB anomalous electrical behavior.
The electrical characteristics of two kinds of n-type SOI-MOSFETs are analyzed and compared in order to build a consistent model. The first kind is an Ultra-Thin Body (UTB) device for which the channel thickness is equal to the initial SOI wafer thickness value (here 46nm). The second kind is what we refer to Nano-Scale Body (NSB) device for which the initial SOI channel is thinned down to 1.6nm using a recessed-gate process. The drain current values were found surprisingly different by three orders of magnitude. Such a huge contrast was not found coherent with the literature, reporting the decrease of the electron mobility with the channel thickness. We interpret our result by the probable influence of an extreme drain-to-source series resistance rather than by vanishing carrier mobility. The interpretation is sustained experimentally by the Rm–L and C–V methods. By integrating a gate-voltage dependence to the series resistance, the linear and saturation regions of the output characteristics of the NSB can be analytically derived from the UTB ones. This simple modeling approach may be useful to interpret anomalous electrical behavior of other nano-devices in which series resistance is of a great concern.