The Scope of Zinc Oxide Bulk Growth

Triboulet, R.; Muñoz‐Sanjosé, V.; Tena‐Zaera, Ramón; Martinez-Tomas, M.C.; Hassani, Saïd

doi:10.1007/1-4020-3475-x_1

Cited by 5 publications

(4 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…What has captured most of the attention in recent years is the fact that ZnO is a semiconductor with a direct band gap of 3.44 eV [7][8][9], which in principle enables optoelectronic applications in the blue and UV regions of the spectrum. The prospect of such applications has been fueled by impressive progress in bulk-crystal [76][77][78] as well as thin-film growth over the past few years [62,[79][80][81][82][83]. A partial list of the properties of ZnO that distinguish it from other semiconductors or oxides or render it useful for applications includes:…”

Section: Properties and Device Applicationsmentioning

confidence: 99%

Fundamentals of zinc oxide as a semiconductor

2009

View full text Add to dashboard Cite

In the past ten years we have witnessed a revival of, and subsequent rapid expansion in, the research on zinc oxide (ZnO) as a semiconductor. Being initially considered as a substrate for GaN and related alloys, the availability of high-quality large bulk single crystals, the strong luminescence demonstrated in optically pumped lasers and the prospects of gaining control over its electrical conductivity have led a large number of groups to turn their research for electronic and photonic devices to ZnO in its own right. The high electron mobility, high thermal conductivity, wide and direct band gap and large exciton binding energy make ZnO suitable for a wide range of devices, including transparent thin-film transistors, photodetectors, light-emitting diodes and laser diodes that operate in the blue and ultraviolet region of the spectrum. In spite of the recent rapid developments, controlling the electrical conductivity of ZnO has remained a major challenge. While a number of research groups have reported achieving p-type ZnO, there are still problems concerning the reproducibility of the results and the stability of the p-type conductivity. Even the cause of the commonly observed unintentional n-type conductivity in as-grown ZnO is still under debate. One approach to address these issues consists of growing high-quality single crystalline bulk and thin films in which the concentrations of impurities and intrinsic defects are controlled. In this review we discuss the status of ZnO as a semiconductor. We first discuss the growth of bulk and epitaxial films, growth conditions and their influence on the incorporation of native defects and impurities. We then present the theory of doping and native defects in ZnO based on density-functional calculations, discussing the stability and electronic structure of native point defects and impurities and their influence on the electrical conductivity and optical properties of ZnO. We pay special attention to the possible causes of the unintentional n-type conductivity, emphasize the role of impurities, critically review the current status of p-type doping and address possible routes to controlling the electrical conductivity in ZnO. Finally, we discuss band-gap engineering using MgZnO and CdZnO alloys.

show abstract

Section: Properties and Device Applicationsmentioning

confidence: 99%

Fundamentals of zinc oxide as a semiconductor

2009

View full text Add to dashboard Cite

show abstract

“…ZnOrdic AB), (b) the high pressure melting technique (MT), explored primarily in USA (Cermet Inc) and (c) the chemical vapour transport (CVT) method, also explored primarily in USA (ZN-Technologies). Despite a very rapid ongoing development of the MT and CVT methods [1,2], the HT method appears to remain superior regarding manufacturing cost, throughput and, ultimately, the substrate size available for device applications. For instance, 2 inch HT bulk ZnO wafers are commercially available at a cost that is gradually decreasing because of the increasing competition between substrate vendors.…”

Section: Bulk Growthmentioning

confidence: 99%

Zinc oxide: bulk growth, role of hydrogen and Schottky diodes

Monakhov¹,

Kuznetsov²,

Svensson³

2009

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Zinc oxide (ZnO) is a wide band gap semiconductor material with attractive features for light emitting devices, photovoltaics, chemical sensors and spintronics. In the past 10 yr ZnO has attracted tremendous interest from the materials science and semiconductor physics research communities, and in this review recent progress in (i) bulk growth, (ii) understanding of the role of hydrogen and (iii) formation of high-quality Schottky barrier (SB) diodes, are discussed for single crystalline ZnO. In (i), the emphasis is put on hydrothermally grown material and how the concentration of intentional and unintentional impurities, such as In and Li, can be controlled and modified by high temperature treatment and defect engineering involving vacancy clusters. In (ii), different possible configurations of hydrogen as a shallow donor are evaluated based on results from calculations employing the density-functional-theory as well as from experimental studies of local vibrational modes using Fourier transform infrared spectroscopy. Further, hydrogen is demonstrated to be very reactive and the interaction with zinc vacancies, group I and group V elements, and transition metals are elucidated. Moreover, the diffusion of hydrogen is found to be rapid and limited by the concentration of traps in hydrothermal samples, and it is argued that isolated (free) hydrogen is not very likely to exist in ZnO at room temperature. In (iii), a compilation of the literature data illustrates that the SB heights for metals deposited on n-type samples have no correlation with the metal work function, violating the fundamental Schottky–Mott model. The role of surface preparation cannot be overestimated and in several cases an oxidation of the surface prior to metal deposition is shown to be beneficial for the formation of high barrier SB diodes. The effects of near-surface defects, such as oxygen vacancies, and contact inhomogeneity are also addressed. However, in spite of the significant progress made in the past 5–7 years, a thorough understanding of the SB formation to ZnO is still lacking. Finally, results from characterization of electrically active point defects employing the SB contacts and junction spectroscopic techniques are reviewed and the identification of some prominent bandgap states is critically evaluated.

show abstract

“…Different crystal growth methods have been used for growing ZnO single crystals,17 in particular: melt, vapor, solution and solvothermal processes.…”

Section: Recent Developments In Solvothermal Crystal Growth Of Materialsmentioning

confidence: 99%

Remarkable Antiagglomeration Effect of a Yeast Biosurfactant, Diacylmannosylerythritol, on Ice‐Water Slurry for Cold Thermal Storage

Kitamoto

Yanagishita

Endo

et al. 2001

Biotechnology Progress

View full text Add to dashboard Cite

Antiagglomeration effects of different surfactants on ice slurry formation were examined to improve the efficiency of an ice-water slurry system to be used for cold thermal storage. Among the chemical surfactants tested, a nonionic surfactant, poly(oxyethylene) sorbitan dioleate, was found to show a greater antiagglomeration effect on the slurry than anionic, cationic, or amphoteric surfactants. More interestingly, diacylmannosylerythritol, a glycolipid biosurfactant produced by a yeast strain of Candida antarctica, exhibited a remarkable effect on the slurry, attaining a high ice packing factor (35%) for 8 h at a biosurfactant concentration of 10 mg/L. These nonionic glycolipid surfactants are likely to effectively adsorb on the ice surface in a highly regulated manner to suppress the agglomeration or growth of the ice particles. This is the first report on the utilization of biosurfactant for thermal energy storage, which may significantly expand the commercial applications of the highly environmentally friendly slurry system.

show abstract

The Scope of Zinc Oxide Bulk Growth

Cited by 5 publications

References 37 publications

Fundamentals of zinc oxide as a semiconductor

Fundamentals of zinc oxide as a semiconductor

Zinc oxide: bulk growth, role of hydrogen and Schottky diodes

Remarkable Antiagglomeration Effect of a Yeast Biosurfactant, Diacylmannosylerythritol, on Ice‐Water Slurry for Cold Thermal Storage

Contact Info

Product

Resources

About