Tellurium assisted realization of p-type N-doped ZnO

Abstract

In this paper, the authors demonstrate an effective pathway to enhance the p-type conduction in N-doped ZnO through codoping method with tellurium during metal-organic chemical vapor deposition process. Tellurium may act as a surfactant in reducing the formation energy of the NO acceptors and thus to enhance the incorporation efficiency of nitrogen. In addition, this codoping method shows a significant effect in suppressing the formation of donorlike carbon related complexes. The increased hole carrier concentration exhibits strong evidence to the enhancement of dopant solubility, and the Te–N codoping method provides an efficient technique for realizing p-type ZnO.

Mutually beneficial doping of tellurium and nitrogen in ZnO films grown by metal-organic chemical vapor deposition

“…19,31 In our previous work, 14 the predominant suppression of the incorporation of carbon impurities, such as carbon clusters and CN complexes, etc., is demonstrated in the Te-N codoped ZnO samples because of the Te assistance. 14 Generally, for the ZnO growth by Me 2 Zn and t-BuOH mixing precursors, the chemical reaction would start by forming an alkylzinc alkoxide (Me-Zn-O-Bu) together with the production of methane. the isopropyl radicals, are believed to assist the heterolysis of the ethyl radicals from the Zn MO precursors, which accelerates the desorption rate of the hydrocarbon species on the growing surface and consequently prevents them from incorporating into the films.…”

“…1(a). 14,22 It is interesting to note that the NH 3 addition causes the diffraction peak to be weaker and broader, indicating its suppression effect on the formation of the ZnTe crystallite. Moreover, a small peak located at 2h ¼ 25.4 can be seen for all the asgrown samples, which cannot be assigned to any of the ZnO related diffraction patterns but is consistent with the (111) orientated ZnTe of the zinc blende structure.…”

“…The early concept was proposed by Porter et al 11,12 The electrical and optical properties of ZnO films codoped with Te and N were investigated but the authors only emphasized the increased resistivity by adding Te in the n-type N-doped ZnO. 14 However, the mechanism beneath is not yet clearly revealed. 14 However, the mechanism beneath is not yet clearly revealed.…”

Structural and optical property characterization of epitaxial ZnO:Te thin films grown by pulsed laser deposition

“…On the other hand, requirement in percentage of Te doping may be less (within few percentages) as the atomic size mismatch with O is large (for the Te at the O site) and raises the valence band significantly upwards compared to S [19]. Few reports exist in the literature on the Te doped ZnO [20][21][22][23][24][25][26][27]. Among these reports, MBE grown films were shown to have Te at both the lattice sites and upon annealing switches to only O site as determined by X-ray photo emission spectroscopy (XPS) [23].…”

“…Few reports exist in the literature on the Te doped ZnO [20][21][22][23][24][25][26][27]. Among these reports, MBE grown films were shown to have Te at both the lattice sites and upon annealing switches to only O site as determined by X-ray photo emission spectroscopy (XPS) [23]. In the present report, we have attempted to grow ZnO: Te by pulsed laser deposition (PLD) on c-plane sapphire and investigated the experimental conditions required for Te incorporation at both the oxygen and zinc site, its solubility and corresponding epitaxial quality and optical band gap.…”