Shunming Zhu

TL;DR: In this paper, the authors show that the visible electroluminescence (EL) at room temperature has been realized based on n-ZnO∕p-Si heterojunction, where the tunneling mechanism via deep-level states was the main conduction process at low forward bias, while space charge-limited current conduction dominated the carrier transport at higher bias.

TL;DR: In this article, the surface morphology with different grain structures has been used to characterize the green photoluminescence of ZnO thin films grown by metal-organic chemical vapor deposition (MOCVD) at varied growth pressures.

TL;DR: In this paper, the realization of ZnO homojunction light-emitting diodes (LEDs) fabricated by metalorganic chemical vapor deposition on (0001) ZNO bulk substrate was reported.

Abstract: The fundamental optical properties of Ga-doped ZnO films grown by metalorganic chemical vapor deposition were investigated by room-temperature transmittance and photoluminescence (PL) spectroscopy. The Burstein–Moss (BM) shift of the absorption edge energy is observed at the carrier concentration up to 2.47×1019cm−3. The absorption edges are fitted to a comprehensive model based on the electronic energy-band structure near critical points plus relevant discrete and continuum excitonic effects, taking account of the Fermi-level filling factor. The theoretical calculation for BM effect is in good agreement with the experimental facts, considering the nonparabolic nature of conduction-band and band-gap renormalization (BGR) effects. Meanwhile, the monotonic redshift of the near-band-gap emission detected by PL measurements has also been observed with increasing free-carrier concentration, which is attributed to the BGR effects, and can be fitted by an n1∕3 power law with a BGR coefficient of 1.3×10−5meVcm.