A Closed-Form Expression of the Drain Current of Asymmetric Double-Gate OTFTs

A continuous, physically based, and analytic current-voltage (I-V) model of asymmetric independent double-gate organic thin-film transistors is presented. The model is worked out from a closed-form solution of Poisson's equation. A fully analytical expression of interface potentials, accumulation charges, and charge carriers, valid in all the regimes of operations, is derived. Charges and potentials are computed by means of a single nonlinear equation that ensures a natural transition between the hyperbolic and trigonometric modes. The drain current is based on the variable-range hopping and accounts for all the regions of operation. The model is validated by comparisons with the full numerical solution and a very good agreement is shown.