1. |
- Malinauskas, T., et al.
(författare)
-
All-optical characterization of carrier lifetimes and diffusion lengths in MOCVD-, ELO-, and HVPE- grown GaN
- 2007
-
Ingår i: Journal of Crystal Growth, Vol. 300. - : Elsevier BV. - 0022-0248. ; , s. 223-227
-
Konferensbidrag (refereegranskat)abstract
- The metrological capability of the picosecond four-wave mixing (FWM) technique for evaluation of the photoelectrical properties of GaN heterostructures grown on sapphire, silicon carbide, and silicon substrates as well as of free-standing GaN films is demonstrated. Carrier recombination and transport features have been studied in a wide excitation, temperature, and dislocation density (from ∼1010 to 106 cm-2) range, exploring non-resonant refractive index modulation by a free carrier plasma. The studies allowed to establish the correlations between the dislocation density and the carrier lifetime, diffusion length, and stimulated emission threshold, to reveal a competition between the bimolecular and nonradiative recombination, and to verify the temperature dependence of bimolecular recombination coefficient in the 10-300 K temperature range. It was shown that the FWM technique is more advantageous than the time-resolved photoluminescence technique for determination of carrier lifetimes in high quality thick III-nitride layers. © 2006 Elsevier B.V. All rights reserved.
|
|