Indium tin oxide

About: Indium tin oxide is a research topic. Over the lifetime, 17857 publications have been published within this topic receiving 402127 citations. The topic is also known as: indium tin oxide.

Origin of open circuit voltage in planar and bulk heterojunction organic thin-film photovoltaics depending on doped transport layers

Abstract: The aim of this article is to investigate the origin of the open circuit voltage (Voc) in organic heterojunction solar cells. The studied devices consist of buckminsterfullerene C60 as acceptor material and an oligophenyl-derivative 4,4′-bis-(N,N-diphenylamino)quaterphenyl (4P-TPD) as donor material. These photoactive materials are sandwiched between indium tin oxide and p-doped hole transport layers. Using two different p-doped hole transport layers, the built-in voltage of the solar cells is independently changed from the metal contacts. The influence of the built-in voltage on the Voc is investigated in bulk and planar heterojunctions. In bulk heterojunctions, in which doped transport layers border directly on the photoactive blend layer, Voc cannot exceed the built-in voltage significantly. Though, in planar heterojunctions, Voc is identical with the splitting of quasi-Fermi levels at the donor-acceptor interface and is thus primarily determined by the difference of the lowest unoccupied molecular orb...

GaN metal-semiconductor-metal ultraviolet photodetectors with transparent indium-tin-oxide Schottky contacts

Abstract: Indium-tin-oxide (ITO) layers were deposited onto n-GaN films and/or glass substrates by electron-beam evaporation. With proper annealing, we found that we could improve the optical properties of the ITO layers and achieve a maximum transmittance of 98% at 360 nm. GaN-based metal-semiconductor-metal (MSM) photodetectors with ITO transparent contacts were also fabricated. A maximum 0.12-A photocurrent with a photocurrent to dark current contrast higher than five orders of magnitude during ultraviolet irradiation were obtained for a photodetector annealed at 600/spl deg/C. We also found that the maximum photo responsivity at 345 nm is 7.2 and 0.9 A/W when the detector is biased at 5 and 0.5 V, respectively.

Work Function Tuning of Reduced Graphene Oxide Thin Films

Abstract: Graphene oxide (GO) has shown great potential as a component in various devices due to its excellent solution processability and two-dimensional structure. However, the oxygenated form of graphene has a moderate charge-transport capability. The latter parameter may be enhanced through controlled deoxygenation of GO with subsequent tuning of its work function (WF). Various reduction approaches were employed to investigate the effect of the oxygen content on the work function of GO derivatives as thin films on an indium tin oxide substrate. Such films were reduced by stepwise thermal annealing in ultrahigh vacuum up to 650 °C, by chemical reduction with hydrazine, or by a combination of chemical and thermal reduction processes. The effect of the GO film thickness and the flake size on the WF was also investigated. UV photoelectron spectroscopy and X-ray photoelectron spectroscopy were used to correlate the WF of GO derivatives with their oxygen content. The results showed that the WF is strongly dependent o...