2-D Numerical-Simulation Of The Charge-Transfer In Gaas Bccds In The Ghz Range

A time-dependent and bidimensional numerical modeling for GaAs BCCD charge-transport analysis is proposed in which Poisson and continuity equations are solved. In this numerical procedure the quasi-Fermi potential φ n or the logarithm of the free-carrier density ln( n ) is solved rather than the variable n . This is due to its gradually changing values on a linear scale when the carrier density n changes drastically on a logarithmic scale. An example of transport modeling is presented which involves the transfer of only one “logic one” in the BCCD channel for a frequency clock of 4 GHz. The charge density is given in the structure versus time and the transfer inefficiency is assessed. Finally the valuation of the dissipated power during the transfer is presented. Compared to other methods these proposed numerical procedures result in a significant reduction in computer time and storage requirement.