Effects of excitation density on cathodoluminescence from GaN

Applied Physics Letters

Volumn 79, Issue 14, 2001, Pages 2154-2156

  Kucheyev, S O ^a   Toth, M ^b,c   Phillips, M R ^b   Williams, J S ^a   Jagadish, C ^a  

^a AUSTRALIAN NATIONAL UNIVERSITY   (Australia)

^b UNIVERSITY OF TECHNOLOGY SYDNEY   (Australia)

^c UNIVERSITY OF CAMBRIDGE   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0035475373     PISSN: 00036951     EISSN: None     Source Type: Journal    
DOI: 10.1063/1.1408273     Document Type: Article

References (13)

1. B. G. Yacobi and D. B. Holt, Cathodoluminescence Microscopy of Inorganic Solids (Plenum, New York, 1990).
2. See, for example, a review, J. W. Orton and C. T. Foxon, Rep. Prog. Phys. 61, 1 (1998).
3. It should be noted that the changing of electron-beam current was done by adjusting the condenser lens strength of the SEM, which also slightly changes beam spot size (see Ref. 4). However, in this case, the changes in excitation density due to a slight variation of beam spot size are negligible compared to those due to a large variation of beam current.
4. See, for example, J. I. Goldstein, D. E. Newbury, P. Echlin, D. C. Joy, A. D. Romig, Jr., C. E. Lyman, C. Fiori, and E. Lifshin, Scanning Electron Microscopy and Microanalysis (Plenum, New York, 1992).
5. In Fig. 2, we show CL data taken at 77 K since DAP emission is observed in GaN only at low temperatures.
6. CL excitation measurements performed at 300 K reveal a similar dependence of the intensities of near-gap and YL emission peaks on beam current in all samples studied.
7. W. Grieshaber, E. F. Schubert, I. D. Goepfert, R. F. Karlicek, Jr., M. J. Schurman, and C. Tran, J. Appl. Phys. 80, 4615 (1996).
8. J. R. Müllhäuser, O. Brandt, H. Yang, and K. H. Ploog, Mater. Res. Soc. Symp. Proc. 395, 607 (1996).
9. 2) with excitation densities in the case of PL measurements is not straightforward particularly for the smallest beam spot sizes. Indeed, the three-dimensional spatial distribution of electron energy loss in the GaN matrix should be taken into account determining beam power density in such cases.
10. K. Fleischer, M. Toth, M. R. Phillips, J. Zou, G. Li, and S. J. Chua, Appl. Phys. Lett. 74, 1114 (1999).
11. D. B. Wittry and D. F. Kyser, J. Appl. Phys. 38, 375 (1967).
12. T. S. Rao-Sahib and D. B. Wittry, J. Appl. Phys. 40, 3745 (1969).
13. H. C. Casey, Jr. and J. S. Jayson, J. Appl. Phys. 42, 2774 (1971).