Role of Structure Sizes in Determining the Characteristics of the Resonant Tunneling Diode.

摘要

Using the Wigner function formalism, we study the effects of structural parameters on the DC I-V characteristics and on the large-signal transient response of the resonant tunneling diode. We model two types of structures of Gallium Arsenide/Aluminum(x)Gallium(1-x)Arsenide; first, with symmetric barriers ranging from 3 to 8 nanometers in thickness separated by a 5 nanometer well, and second with a well varying 3 to 8 nanometers between 3 nanometer barriers. Experimental variation of the barrier thickness and height changes the peak-to-valley ratio in the I-V curve, as predicted by elementary models of tunneling structures. This stems directly from the changes in tunneling probabilities. For the DC studies, we show that the peak-to-valley ratio in the I-V curve is a function of the resonance width, which depends both on the well and barrier thickness. The location of the peak on the I-V curve depends on the location of the resonant energy, which is a function of the well width. Transient switching behavior is compared to earlier numerical studies of tunneling times of wave packets. Charge storage stabilizes the position of the resonant state, thus damping the transients. Semiconductors; transport; Hot carriers; Quantum effects; Reprints; Solid state electronics; Resonant tunneling diode; Wigner function. (jg)