Free-carrier contribution to the optical response of N-rich Cu₃N thin films

Abstract

The influence of nitrogen excess on the optical response of N-rich Cu 3 N films is reported. The optical spectra measured in the wavelength range from 0.30 to 20.00 µm have been correlated with the elemental film composition which can be adjusted in the nitrogen atomic percentage (at%) range from 27 ± 2 up to 33 ± 2. The absorption spectra for the N-rich films are consistent with direct optical transitions corresponding to the stoichiometric semiconductor Cu 3 N plus a free-carrier contribution that can be tuned in accordance with the N-excess. The data are consistent with the incorporation of the excess N in the lattice as an electron acceptor that generates free holes.

Ti substituted nano-crystalline Cu3N thin films

“…In most works, the stoichiometry of Cu 3 N thin films has been deduced from XRD data (having a change in the lattice parameter). 7,[15][16][17]26 The lattice constant has been estimated from the position of the Cu 3 N (100) diffraction peak. The evolution of the film lattice constant is due to the variation in nitrogen stoichiometry.…”

“…Most publications have dealt with reactive magnetron sputter deposition and the characterization of the physical properties of the Cu 3 N films as a function of deposition parameters: nitrogen (partial) pressure in the gas mixture, [15][16][17] substrate temperature, 7,18 and sputtering power. 19,20 Although Cu 3 N has been widely studied, little information is available in the literature concerning transition metal-doped Cu 3 N. Recently, some ternary compound based Cu 3 N have been grown; (Pd, Cu)N, 21 (Ti, Cu)N, 22 and (Ag, Cu)N. 23 Also, Moreno-Armenta et al 24 have theoretically studied the effect of metal insertion (M = Ni, Cu, Zn, Pd, Ag, and Cd) at the center of Cu 3 N unit cell on electronic structure.…”

Thermal stability of copper nitride thin films: The role of nitrogen migration

“…More details about the optical model and the fitting procedure are described in Ref. 35. The calculated layer thickness and their free carrier density are listed in Table I.…”

Stopping power dependence of nitrogen sputtering yields in copper nitride films under swift-ion irradiation: Exciton model approach

“…The ToF-E detector is located at a scattering angle of 44°. The analyzed area was about 2x1 mm 2 and it was characterized after the irradiations by measuring the size of the beam spot that was visible after irradiation. The charge was measured using the RBS signal from gold for a gold coated rotating vane that periodically intercepts the ion beam.…”

“…Copper nitride is a semiconducting material with an optical bandgap of around 1 eV [1][2][3] which presents a cubic lattice structure. Cu 3 N thin films are usually deposited by sputtering [4,5].…”