Interface trap density and mobility extraction in InGaAs buried quantum well metal-oxide-semiconductor field-effect-transistors by gated Hall method

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Chidambaram, Thenappan
Veksler, Dmitry
Madisetti, Shailesh
Greene, Andrew
Yakimov, Michael
Tokranov, Vadim
Hill, Richard
Oktyabrsky, Serge
Applied Physics Letters
gated Hall method , free carrier density , electron mobility , quantum wells , temperature dependence , electron mobility , Coulomb scattering , electron density , interface/border traps , capacitance-voltage measurement , electrostatic modeling , fast traps , free channel carrier , channel density , carrier mobility
In this work, we are using a gated Hall method for measurement of free carrier density and electron mobility in buried InGaAs quantum well metal-oxide-semiconductor field-effect-transistor channels. At room temperature, mobility over 8000 cm2/Vs is observed at ~1.4 10 12 cm-2. Temperature dependence of the electron mobility gives the evidence that remote Coulomb scattering dominates at electron density <2 10 11 cm -2. Spectrum of the interface/border traps is quantified from comparison of Hall data with capacitance-voltage measurements or electrostatic modeling. Above the threshold voltage, gate control is strongly limited by fast traps that cannot be distinguished from free channel carriers just by capacitance-based methods and can be the reason for significant overestimation of channel density and underestimation of carrier mobility from transistor measurements.