Growth and characterization of GaInNxAs1-x thin films with band-gap energies in the red-blue portion of the visible spectrum

Using the radio-frequency (rf) sputtering deposition technique, we have grown GaInNxAs1-x thin films on glass substrates at room temperature. The concentration of nitrogen in the films was found to depend mainly on the rf power used to excite the growth plasma. X-ray diffractograms show that the films have small grain sizes and present a broad diffraction band centered close to the (002) diffraction peak of hexagonal GaN. Electron dispersive spectroscopy measurements report N concentrations of xsimilar to0.8 and In concentrations of about 3% indicating that we have grown GaInNxAs1-x alloys in the GaN-rich side. The absorption spectra measured by the photoacoustic technique show that these semiconductor films have band-gap energies ranging between 1.69 and 2.56 eV, when the rf sputtering power is varied in the range 30-80 W. Thus, we show the feasibility to grow GaInNxAs1-x thin films with high N concentrations in which we can tune the band-gap energy in the red-blue portion of the visible spectrum, by a careful control of the growth parameters. (C) 2002 American Institute of Physics.