Effective mass in the barriers of GaAs/AlAs resonant tunneling double barrier diodes

Abstract

We have investigated the peak and valley currents for a series of resonant tunneling diodes with AlAs barriers having widths in the range 1.9–5.9 nm and GaAs wells fabricated on GaAs substrates. Using a simple WKB expression that assumes resonant tunneling dominated by transfer through the Γ-Γ conduction band edge, a value for the strength, m b ∗V b , of our AlAs barriers is found to be 0.069 ± 0.01 eV and the effective mass is found to be m b = (0.068 ± 0.01) m 0. This agrees to within the measurement error with the result obtained for a series of diodes fabricated on InP by Broekaert et al. 1 with In 0.53Ga 0.47As wells and pseudomorphic AlAs barriers. The measured peak currents are compared with the results of self-consistent numerical solutions of Poisson's and Schroedinger's equations using the deduced effective mass.