Our simulated results [Appl. Phys. Lett. 98, 101110 (2011)] reveal that polarization-doped light-emitting diodes (LEDs) have improved internal quantum efficiency due to the enhanced hole injection caused by the improved hole concentration and smooth valence band. In this letter, in order to verify these calculated results, polarization-doped LEDs grown by metalorganic chemical vapor deposition are investigated. The results show that the polarization-doped LED has the improved electroluminescence intensity and external quantum efficiency (EQE) compared with the conventional LED. The influence of the degree of AlGaN gradation on polarization-doped LEDs is also studied. It is found that the polarization-doped LED has the highest EQE when the Al composition of the graded AlGaN is linearly decreased from 0.2 to 0.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.