Interface roughness scattering effect on electrical properties of heterojunctions

In the present work, the effect of roughness in resonant tunneling diodes has been considered to track two main goals. At first, the roughness impact on the transport through these heterojunctions has been studied before investigating the roughness type effect. For calculating the electrical transport, the transfer matrix technique has been used in the simulations. Two different standard methods of deposition - Random deposition (RD), and Ballistic deposition (BD)- have been applied to generate two dissimilar rough interfaces. The scattering process reduces the transport probability. The conductivity as a function of voltage has also been calculated. Effect of interface roughness on the peak-tovalley current ratio in the presence of roughness has been discussed. The results show that the scattering effect it significant. As the applied voltage increases, at first, the value of current reaches its maximum amount, and then with increasing the voltage, the current falls in a negative differential resistance region.