Study of GaNxAs1−x semiconducting films grown by laser pulsed deposition on crystalline and amorphous substrates

Abstract

The search for semiconductors with band gap energies in the green–blue region of the visible spectra has stimulated the development of new ternaries in the II–VI and III-nitrides systems. In the GaN-side of the GaNAs ternary compound it is expected that the band gap energy could be adjusted for all the visible spectra by changing the N concentration in the compound. We report on the growth of the ternary compound semiconductor GaNxAs1−x thin films by using the laser ablation deposition technique in a reactive nitrogen gas atmosphere, on crystalline GaAs(100) and Si(001) substrates and also on Corning glass substrates. We have studied the optical properties of these GaNxAs1−x films by means of the photoacoustic (PA) and the low temperature photoluminescence (PL) spectroscopies. PL spectra for GaNAs samples showed a broad emission band peaked at around 2.50eV, a weak broad emission band at about 3.05eV, and a double-peaked structure located at energies corresponding to violet luminescence band; besides, a very weak emission could be measured at energies of about 1.65–1.68eV. We interpret these results in terms of the presence of the ternary GaNAs phase and cubic and hexagonal GaN phases.