Experimental Determination of Quantum and Centroid Capacitance in Arsenide-Antimonide Quantum-Well MOSFETs Incorporating Nonparabolicity Effect

Experimental gate capacitance (C-g) versus gate voltage data for InAs0.8Sb0.2 quantum-well MOSFET (QW-MOSFET) is analyzed using a physics-based analytical model to obtain the quantum capacitance (C-Q) and centroid capacitance (C-cent). The nonparabolic electronic band structure of the InAs0.8Sb0.2 QW is incorporated in the model. The effective mass extracted from Shubnikov-de Haas magnetotransport measurements is in excellent agreement with that extracted from capacitance measurements. Our analysis confirms that in the operational range of InAs0.8Sb0.2 QW-MOSFETs, quantization and nonparabolicity in the QW enhance C-Q and C-cent. Our quantitative model also provides an accurate estimate of the various contributing factors toward C-g scaling in future arsenide-antimonide MOSFETs.