Temperature and excitation power dependence of photoluminescence of ZnO nanorods synthesized by pattern assisted hydrothermal method

Abstract

Pattern assisted ZnO nanorods (NRs) growth are performed using electron beam lithography (EBL) and hydrothermal method. The patterns of lines, circles and squares are prepared on polycrystalline ZnO seed layer using PMMA as photoresist. It is found that the ZnO NRs can only grow on the area with ZnO seed layer, not on the PMMA surface. The TEM results show that the ZnO NRs have single crystal structures with good orentation along the c-axis. The excitation power dependence of photoluminescence (PL) spectra of ZnO NRs shows that with excitation power increasing, the near band edge emission increases rapidly than the defects related visible emissions. The temperature dependence of PL spectra was measured in the temperature range of 13-300 K. The dependence of peak position and peak energy of exciton bound (D 0 X) emission of ZnO NRs on temperature were analyzed. Two non-radiative recombination channels for the D 0 X emission are discussed in detail.

Synthesis of Magnesium-Doped ZnO Rods via Hydrothermal Method: A Study of the Structural and Optical Properties

“…7,8 ZnO is a semiconductor compound and belongs to the VI-II group. It has a wide bandgap with energy equal to 3.37 eV at room temperature, 9,10 which is near the UV spectral region, and exciton binding energy of 60 meV. 11,12 These characteristics of ZnO place it among the most prominent materials for various applications.…”

Anisotropic photoluminescence of nonpolar ZnO epilayers and ZnO/Zn1-xMgxO multiple quantum wells grown on LiGaO2 substrate

“…Figure 3(a) shows the 90°polarized PL spectra of the m-plane ZnO epilayer at 10-300 K. A moderate emission at 3.260 eV and a strong emission at 3.221 eV with a full width at half maximum (FWHM) of 25 meV are observed at 10 K. The former corresponds to the near band edge (NBE) exciton emission (superposition of donor bound exciton D 0 X and free exciton FX) [26,27], whereas the latter is a BSF related emission [20,28]. The strong BSFs related peak is the result of the high density of BSFs of 1×10 6 cm −1 in the epilayer reported previously [22].…”