Growth of zinc oxide by chemical vapor transport

Mikami, Masaki; Eto, Toshiaki; Wang, Jifeng; Masa, Y.; Isshiki, Minoru

doi:10.1016/j.jcrysgro.2004.11.431

Cited by 46 publications

(49 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hence the red/orange photoluminescence band at 1.902 eV may be attributed to this transition. Interestingly, the red/orange coloration has been shown 50,51 for as-prepared samples and those annealed under Zn vapor. The samples become transparent upon annealing under O vapor and the red coloration is reversible.…”

Section: Origin Of Luminescencementioning

confidence: 97%

Energetics of intrinsic defects and their complexes in ZnO investigated by density functional calculations

et al. 2011

View full text Add to dashboard Cite

Formation energies of various intrinsic defects and defect complexes in ZnO have been calculated using a density-functional-theory-based pseudopotential all-electron method. The various defects considered are oxygen vacancy ( Upon comparing the formation energies of these defects, we find that V O would be the dominant intrinsic defect under both Zn-rich and O-rich conditions and it is a deep double donor. Both Zn O and Zn i are found to be shallow donors. The low formation energy of donor-type intrinsic defects could lead to difficulty in achieving p-type conductivity in ZnO. Defect complexes have charge transitions deep inside the band gap. The red, yellow, and green photoluminescence peaks of undoped samples can be assigned to some of the defect complexes considered. It is believed that the red luminescence originates from an electronic transition in V O , but we find that it can originate from the antisite Zn O defect. Charge density and electron-localization function analyses have been used to understand the effect of these defects on the ZnO lattice. The electronic structure of ZnO with intrinsic defects has been studied using density-of-states and electronic band structure plots. The acceptor levels introduced by V Zn are relatively localized, making it difficult to achieve p-type conductivity with sufficient hole mobility.

show abstract

Section: Origin Of Luminescencementioning

confidence: 97%

Energetics of intrinsic defects and their complexes in ZnO investigated by density functional calculations

et al. 2011

View full text Add to dashboard Cite

show abstract

“…It has been well established that the growth of ZnO by vapour transport in closed ampoules at moderate temperatures (∼1000°C) and temperature gradients results in very low growth rates in absence of other species [11,12]. We refer them as "additional species" and we can find a good variety in literature: F 2 [13], Cl 2 [5,6,13,14], Br 2 [13,14], I 2 [13], HF [13], HCl [5,[13][14][15], HBr [14,15], HI [15], NH 3 [5], NH 4 Cl [14,15], NH 4 Br [14,15], ZnCl 2 [15,16], HgCl 2 [5,17,19], Zn [16,18], H 2 [5,20,21], C [6,21,23] and different mixtures: H 2 O+H 2 [2,20], H 2 +C+H 2 O [24] and N 2 +C+H 2 O [24].…”

Section: Introductionmentioning

confidence: 99%

“…One way to avoid this reaction is the deposition of a graphite layer on the inner ampoule walls [6]. Nevertheless, the ZnO crystals obtained in graphitised ampoules www.crt-journal.org generally present an orange colour and a post-growth annealing in an O 2 atmosphere has been needed to obtain colourless crystals [22][23][24]. Literature associates the orange colour to the existence of some intrinsic donor defects [25][26][27], but the chemical nature of the point defects responsible of these donor levels is a controversial subject [28].…”

Section: Introductionmentioning

confidence: 99%

Growth of ZnO crystals by vapour transport: Some ways to act on physical properties

Tena‐Zaera

Martı́nez-Tomás

Gómez‐García

et al. 2006

Cryst. Res. Technol.

View full text Add to dashboard Cite

Nowadays, the growth of ZnO by vapor transport in silica ampoules is generally made in presence of graphite. As it has been already shown, this means that the growth process is carried out in presence of a Zn excess. In order to control that and act, as a consequence, on the physical properties of crystals we have performed a systematic study of the growth process in a wide range of Zn excess compositions using well defined experimental conditions. As a preliminary characterization, optical absorption and electrical properties have been analyzed at room temperature. The results show how some physical properties of asgrown ZnO crystals can be changed in a controlled way by an adequate combination of different growth conditions such as graphite covering of inner ampoule walls, thermal difference between source material and crystallization zone and additional gas (composition and pressure). In this frame some post-growth annealing processes can be avoided reducing the time and cost of processes.

show abstract

“…In general the nanostructures might be applied for blue semiconductor lasers due to its wide band gap (3.37 eV) and high exciton binding energy (60 meV) [10], transparent semiconductor [11], piezoelectric [12], short-wavelength lightemitting devices [13], blue emitting LEDs [14], chemical sensor [15], solar cells [16], etc. Several methods for the production of this kind of nanomaterials have been described, such as, electrodepositing [17], evaporation [18], vapor-liquid-solid (VLS) growth [19], metal organic catalyst assisted vapor-phase epitaxy [20], aqueous thermal decomposition [21], microwave activated chemical bath deposition (MW-CBD) [22], chemical bath deposition (CBD) [23], and surfactant-assisted hydrothermal method [24]. This last method is more convenient than others because it is less expensive; it has an easier composition control; the coating can be deposited on large area.…”

Section: Introductionmentioning

confidence: 99%

Monodisperse ZnO Solid Spheres by an Assisted Structure Directing Agent-Hydrothermal Method

López-Romero¹,

Jiménez²

2015

WJCMP

View full text Add to dashboard Cite

Monodisperse ZnO solid spheres nanostructures were synthesized and deposited on Si (100) silicon substrates by the hexamethylenetetramine (HMTA)-assisted hydrothermal method at high temperature (200˚C). In this case the HMTA is used as structure directing agent (SDA) to growth of the ZnO solid spheres. The source material used was zinc nitrate hexahydrate under a chemical reaction of hydrolysis-condensation of the Zn 2+ salt aqueous solution. The structure and morphology of the ZnO solid spheres were studied by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Furthermore, the photoluminescence (PL) of the ZnO solid spheres was measured to optical characterization of the product. The remarkable influence of the HMTA as structure directing agent and the reaction temperature to the formation of the solid spheres nanostructures is demonstrated.

show abstract

Growth of zinc oxide by chemical vapor transport

Cited by 46 publications

References 6 publications

Energetics of intrinsic defects and their complexes in ZnO investigated by density functional calculations

Energetics of intrinsic defects and their complexes in ZnO investigated by density functional calculations

Growth of ZnO crystals by vapour transport: Some ways to act on physical properties

Monodisperse ZnO Solid Spheres by an Assisted Structure Directing Agent-Hydrothermal Method

Contact Info

Product

Resources

About