Home

About

Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network
FAQHELPSITE MAPCONTACT US


  Advanced Search  

 
Optical and x-ray diffraction studies on the incorporation of carbon as a dopant in cubic GaN J. R. L. Fernandez, F. Cerdeira, E. A. Meneses, and M. J. S. P. Brasil
 

Summary: Optical and x-ray diffraction studies on the incorporation of carbon as a dopant in cubic GaN
J. R. L. Fernandez, F. Cerdeira, E. A. Meneses, and M. J. S. P. Brasil
Instituto de Fi´sica ``Gleb Wataghin,'' Universidade Estadual de Campinas, Caixa Postal 6165, 13083-970 Campinas, Sa~o Paulo, Brazil
J. A. N. T. Soares,* A. M. Santos, O. C. Noriega, and J. R. Leite
Instituto de Fi´sica, Universidade de Sa~o Paulo, Caixa Postal 66318, Sa~o Paulo, Sa~o Paulo, Brazil
D. J. As, U. Ko¨hler, S. Potthast, and D. G. Pacheco-Salazar
Universita¨t Paderborn, FB-6 Physik, D-33095 Paderborn, Germany
Received 28 February 2003; revised manuscript received 26 June 2003; published 17 October 2003
We performed optical and x-ray diffraction experiments on carbon doped cubic-GaN samples, deposited by
plasma-assisted molecular beam epitaxy on 001 GaAs substrates, for various carbon concentrations. The
samples were studied by Raman, photoluminescence, and photoluminescence excitation spectroscopies. These
techniques give some insight into the mechanism of carbon incorporation in the material. Detailed analysis of
these spectra leads to a picture in which carbon initially enters into N vacancies producing a marked improve-
ment in the crystalline properties of the material. At higher concentrations it also begins to enter interstitially
and form C complexes, with a consequent decrease of crystalline quality. This increase and later decrease of
crystalline quality of our samples with the addition of C were also detectable in x-ray diffraction scans. A
model calculation of the localized vibrations of the C atom in the GaN lattice allows for the interpretation of
a feature in the Raman spectrum of some samples, which reinforces this view.
DOI: 10.1103/PhysRevB.68.155204 PACS number s : 78.20. e, 78.30.Fs, 78.55.Cr
I. INTRODUCTION

  

Source: As, Donat Josef - Department Physik, Universität Paderborn

 

Collections: Materials Science; Physics