Abstract: Using the scattering matrix method, we study the characteristics of electronic tunneling a double square barrier. Taking into account the tunneling current with ballistic and diffusive components,we present the resuits of ballistic component for oscillation of the transmission coefficient,while the diffusive one leads to decay. It is shown that the overall transmission coefficient of the double-barrier potential is related to the height of potemtial barrier and the matching of incident wave and the out wave. The conclusions are confirmed by the numerical results.

Key words: double-barrier, quantum tunneling, scattering matrix, coherent transport