A compact drain current model of short-channel cylindrical gate-all-around MOSFETs

Abstract

A fully analytical potential model, valid in the weak inversion regime of short-channel cylindrical gate-all-around (GAA) MOSFET, is proposed. The model derivation is based on a previous analytical expression for tetragonal GAA MOSFET and the rotational symmetry of the tetragonal cross section. Device simulations were performed to verify that the potential distribution along the channel is properly described in all positions within the silicon body. Using the potential model, analytical expressions for the threshold voltage, subthreshold swing and drain-induced barrier lowering have been derived. Including the short-channel effects within an existing model for the subthreshold leakage current and an analytical drain current model of long-channel devices in strong inversion, a compact drain current model has been derived describing with good accuracy the transfer and output characteristics of short-channel GAA MOSFETs in all regions of operation.

Analytic drain current model for III–V cylindrical nanowire transistors

“…The model presented here differs from previous studies in the literature in three main aspects: (1) It uses Fermi-Dirac statistics instead of simplified Boltzmann-Maxwell ones [5][6][7][8] to describe the electron state occupation in III-V semiconductors properly without making any approximation for the Fermi-Dirac integral. 9 (2) It accounts for the electron quantum nature (observed in small NWs 10,11 ) avoiding classical depictions [12][13][14][15] of the charge. For this, we extend the results of a Q-V model presented in a previous work 16 (by successfully solving the Schr€ odinger and Poisson equations for an arbitrary number of subbands).…”

Channel doping-dependent analytical model for symmetric double gate metal-oxide-semiconductor field-effect transistor. II. Continuous drain current model from subthreshold to inversion region

“…15 In the inversion region, the mobile carriers in the channel cannot be neglected anymore. Due to the long channel approximation, we can solve the modified 1D Poisson's equation described as…”

An analytical model for square GAA MOSFETs including quantum effects

“…As can be seen, the results for the two devices are found to be almost identical. Analytical models for the electrostatic potential of cylindrical GAA devices are available in the literature [9,34,35], and here we have modeled the potential at the center of a square GAA MOSFET making use of the expression proposed in [9]. Thus, the C c term can be calculated as [32]:…”