EFFECT OF THE EXTRINSIC AND TEMPORAL CARRIERS ON RADIATIVE RECOMBINATION OF III-NITRIDE NANOSTRUCTURES

Document Type: Regular Paper

Authors

1 1Department of Basic Science, Islamic Azad University, Damghan Branch, Damghan, I. R. of Iran

2 Department of Physics, Shahrood University of Technology, 3619995161, P.O. Box 316, Shahrood, I. R. of Iran

3 Department of Basic Science, Islamic Azad University, Damghan Branch, Damghan, I. R. of Iran

4 Department of Physics, Chemistry and Biology, Linkoping University, SE-581 581 83 Linkoping, Sweden

Abstract

Due to many important applications, the group III-Nitride semiconductors have recently attracted
remarkable attention among semiconductor researchers and engineers. In this paper, we report on the impact of extrinsic and temporal carriers on the screening of polarization internal fields. The optical efficiency of GaN/AlGaN multiple quantum well (MQW) nanostructures were studied by means of photoluminescence
(PL) and time-resolved PL measurements. Extrinsic carriers come from Si doping in the barriers, while
temporal carriers originate when the samples are excited by laser beam. The emission peaks of MQWs in PL
spectra of the undoped and low-doped samples show a shift towards higher energy levels as excitation
intensity increases, while the other samples do not exhibit such a phenomenon due to the dominance of the
extrinsic carriers. The transient data confirm the results of the PL measurements.

Keywords