Pulsed laser deposition of ZnSe:N epilayers assisted by active atomic nitrogen beams

Abstract

Abstract Epilayers of ZnSe doped with nitrogen have been grown on polished GaAs(1 0 0) and Si(1 0 0) substrates by pulsed laser deposition (PLD) assisted by atomic nitrogen beams. An arc-heated beam source was used to dissociate N 2 and produced neutral nitrogen atom beams with concentration of 10 17 –10 19 at. sr −1 s −1 , which intersected with laser ablated plumes and substrate surfaces in the process of deposition. X-ray diffraction (XRD) results indicate that the ZnSe film grown on GaAs(1 0 0) at 2×10 −3 Torr is a single crystalline epitaxial layer. XRD analysis gives that the crystallographic quality of PLAD-grown ZnSe thin films largely depends on ambient pressure and lattice match. X-ray photoelectron spectroscopy (XPS) demonstrates that Zn and Se atoms in the PLD-grown ZnSe epilayers on GaAs(1 0 0) at 2×10 −3 Torr bonded each other, and besides 11% [N] and 5% [O] no other impurity exist. The concentration of doped nitrogen for the best ZnSe thin film grown on GaAs(1 0 0) was estimated to be over 10 21 cm −3 .