DSpace at IIT Bombay >
IITB Publications >
Please use this identifier to cite or link to this item:
|Title: ||Spectroscopic ellipsometry studies of reactively sputtered nitrogen-rich GaAsN films|
|Authors: ||BISWAS, A|
|Keywords: ||BAND-GAP ENERGY|
|Issue Date: ||2011|
|Publisher: ||ELSEVIER SCIENCE BV|
|Citation: ||JOURNAL OF NON-CRYSTALLINE SOLIDS,357(18)3293-3300|
|Abstract: ||Nitrogen-rich GaAsN thin films have been deposited at 500 degrees C by reactive rf sputtering of GaAs target in argon nitrogen atmosphere. The arsenic content of the films was varied by changing the nitrogen percentage in the sputtering atmosphere and the As/Ga ratio in the films was estimated by X-ray fluorescence measurements. Spectroscopic ellipsometry measurements have been carried out on these films and the measured ellispometric spectra were fitted with theoretical spectra generated by using suitable model sample structures. From the best fit parameters of the dispersion model, band-gap values and variation of refractive index and extinction coefficient as a function of wavelength have been obtained for films deposited with different percentages of nitrogen in the sputtering atmosphere. The films deposited with 12% to 100% nitrogen in the sputtering atmosphere, which are of hexagonal GaN, exhibit GaN-like optical properties, though effects due to excess arsenic in amorphous phase are seen in the films deposited with less than 40% nitrogen. The films deposited with 5% to 12% nitrogen in sputtering atmosphere are dominantly polycrystalline GaAsxN(1-x), (x approximate to 0.01 to 0.08) and exhibit variations in optical parameters, which are consistent with their structure and composition. The films deposited with less than 5% nitrogen in sputtering atmosphere are arsenic-rich and amorphous. (C) 2011 Elsevier B.V. All rights reserved.|
|Appears in Collections:||Article|
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.