Two dimensionally patterned GaN_xAs_1-x/GaAs nanostructures using N⁺ implantation followed by pulsed laser melting

We present measurements on two dimensionally patterned GaN_xAs_1-x dots fabricated in a GaAs matrix using ion implantation followed by pulsed laser melting and rapid thermal annealing. The lithographically patterned GaN_xAs_1-x regions are imaged by ballistic electron emission microscopy (BEEM). By analyzing the BEEM spectra of the locally confined dots, we observe the decrease in the Schottky barrier height with nitrogen incorporation. The second derivatives of BEEM currents from unpatterned GaN_xAs_1-x films exhibit a decrease in Γ-like thresholds as the nitrogen concentration increases. The composition dependence of the thresholds agrees well with that of previously studied low temperature molecular beam epitaxy grown alloys.