低温光导型InSb红外探测器研究

文中讨论了决定光导型探测器性能的主要因素。在理论分析的基础上 ,对低温单元光导InSb探测器的主要工艺参数进行分析和估算。

Commercial indium-tin oxide glass:A catalyst electrode for efficient N_(2)reduction at ambient conditions

The typical Haber technical process for industrial NH_(3)production involves plenty of energy-consumption and large quantities of greenhouse gas emission.In contrast,electrochemical N_(2)reduction proffers environment-friendly and energy-efficient avenues to synthesize NH_(3)at mild conditions but demands efficient electrocatalysts for the N_(2)reduction reaction(NRR).Herein we report for the first time that commercial indium-tin oxide glass(ITO/G)can be used as a catalyst electrode toward artificial N_(2)fixation,as it demonstrates excellent selectivity at mild conditions.Such ITO/G delivers excellent NRR performance with a NH_(3)yield of 1.06×10^(-10) mol s^(-1) cm^(-2) and a faradaic efficiency of 6.17%at-0.40 V versus the reversible hydrogen electrode(RHE)in 0.5 M LiClO4.Furthermore,the ITO/G also possesses good electrochemical stability and durability.Finally,the possible reaction mechanism for the NRR on the ITO catalysts was explored using first-principles calculations.

Preparation of High Quality Indium Tin Oxide Film on a Microbial Cellulose Membrane Using Radio Frequency Magnetron Sputtering

Microbial cellulose （MC） membranes produced by Acetobacter xylinum NUST4.1,were used as flexible substrates for the fabrication of transparent indium tin oxide （ITO） electrodes.Transparent and conductive ITO thin films were deposited on MC membrane at room temperature using radio frequency （RF） magnetron sputtering.The optimum ITO deposition conditions were achieved by examining crystalline structure,surface morphology and op-toelectrical characteristics with X-ray diffraction （XRD）,scanning electron microscopy （SEM）,atomic force mi-croscopy （AFM）,and UV spectroscopy.The sheet resistance of the samples was measured with a four-point probe and the resistivity of the film was calculated.The results reveal that the preferred orientation of the deposited ITO crystals is strongly dependent upon with oxygen content （O2/Ar,volume ratio） in the sputtering chamber.And the ITO crystalline structure directly determines the conductivity of ITO-deposited films.High conductive [sheet resis-tance ～120 Ω·square-1 （Ω·sq-1）] and transparent （above 76%） ITO thin films （240 nm thick） were obtained with a moderate sputtering power （about 60 W） and with an oxygen flow rate of 0.25 ml·min-1 （sccm） during the deposi-tion.These results show that the ITO-MC electrodes can find their potential application in optoelectrical devices.

Isothermal thermo-analytical study and decomposition kinetics of non-activated and mechanically activated indium tin oxide(ITO) scrap powders treated by alkaline solution

Isothermal decomposition process of chemically transforming indium tin oxide（ITO） powders into indium（III） hydroxide powders was investigated. Two types of powders were analyzed, i.e., non-activated and mechanically activated. It has been found that in the case of activated sample, shorter induction periods appear, which permits growth of smaller crystals, while in the case of non-activated sample, long induction periods appear, characterized by the growth of larger crystals. DAEM approach has shown that decomposition processes of non-activated and mechanically activated samples can be described by contracting volume model with a linear combination of two different density distribution functions of apparent activation energies（Ea）, and with first-order model, with a single symmetrical density distribution function of Ea, respectively. It was established that specific characteristics of particles not only affect the mechanism of decomposition processes, but also have the significant impact on thermodynamic properties.

Preparation and Characterization of Indium Doped Tin Oxide （ITO） via a Solvothermal Method

Tin-doped Indium Oxide （ITO） has been successfully prepared via solvothermal method with a mixture of Indium（Ill） acetylacetonate and Tin（IV） bis（acetylacetonate）dichioride in oleyamine solvent under the condition of the different reaction time from 12 h to 48 h for the first time. The morphology, phase composition and particle size of the ITO powder were characterized by TEM and XRD. Two significant properties required for ITO samples to become noncarbon support for Pt in PEMFCs including specific surface area and electrical conductivity were studied.

Removal of tin and extraction of indium from acid-dissolved solution of waste indium-tin targets

The recovery of indium from waste indium tin oxide （ITO） target has great significance for the economy and environment.Based on our previous study on the optimization of acid leaching technique,the present study focuses on tin removal via zinc substitution and indium recovery from a tin-free leach solution.The results show that when the amount of added zinc powder and reaction time increase,the tin removal effect can be improved.The optimal conditions obtained are as follows：additional content of zinc powder from 20 g/L to 25 g/L,reaction temperature of 60 ℃,and reaction time from 3 h to 4 h.Under this condition,the tin removal rate exceeds 98%,and the tin content in the tin removal solution is lower than 0.05 g/L.After tin removal,the substitution time could be reduced from 3-5 d to 1-2 d by neutralizing the residual acid by using alkaline residue and maintaining the pH value less than 2.The indium recovery rate is also improved when this condition is used.The indium content in the tin residue is reduced to lower than 0.1% and the acid-insoluble β-SnO2 could be obtained via the strong nitric acid leaching of the indium-containing tin residue.Indium could be recovered from ITO with a high purity of 99.995% via electrorefining.

Reactive Ion Etching of ITO Transparent Electrode of TFT-AMLCD in Ar/CF_4 Plasma

The pattern of ITO transparent electrode of pixel cells in TFT-AMLCD is a critical step in the manufacturing process of flat panel display devices,the development of suitable plasma reactive ion etching is necessary to achieve high resolution display.In this work we investigated the Ar/CF 4 plasma etching of ITO as function of different parameters.We demonstrated the ability of this plasma to etch ITO and achieved an etching rate of about 3.73 nm/min,which is expected to increase for long pumping down period,and also through addition of hydrogen in the plasma.Furthermore we described the ITO etching mechanism in Ar/CF 4 plasma.The investigation of selectivity showed to be very low over silicon nitride and silicon dioxide but very high over aluminum.

Oxygen Induced Limitation on Grain Growth in RF Sputtered Indium Tin Oxide Thin Films

ITO （indium tin oxide） thin films were deposited onto glass substrates by RF （radio frequency） magnetron sputtering to study variation of grain growth in pure argon and 99% argon plus 1% oxygen at different substrate temperatures. The average grain size increased with the increasing substrate temperature in pure argon. However, in oxygen presence environment the grain growth is limited at above 150 ℃. The films optoelectronic properties were evaluated. It was found that 200 nm ITO films prepared at 220 ℃ substrate temperature in pure argon possessed optimum sheet resistance of 10 Ω/sq. The transmittance oflTO films was enhanced with increasing the substrate temperature in pure argon but limited by the presence of excess oxygen.

Flexible and stretchable electrodes for next generation polymer electronics: a review

Transparent conductive electrodes play a significant role in the fabrication and development of optoelectronic devices. As next generation optoelectronic devices tend towards mobile and wearable devices, the added attribute of flexibility or stretchability for these electrodes becomes increasingly important. However, mechanical requirements aside, transparent conductive electrodes must still retain high transparency and conductivity, with the metrics for these parameters being compared to the standard, indium tin oxide. In the search to replace indium tin oxide, two materials that have risen to the forefront are carbon nanotubes and silver nanowires due to their high transparency, conductivity, mechanical compliance, and ease of fabrication. This review highlights recent innovations made by our group in electrodes utilizing carbon nanotubes and silver nanowires, in addition to the use of these electrodes in discrete devices and integrated systems.

High efficiency organic light-emitting diodes using CuO_x/Cu dual buffer layers

An organic light-emitting diode （OLED） device with high efficiency and brightness is fabricated by inserting CuOJCu dual inorganic buffer layers between indium-tin-oxide （ITO） and hole-transport layer （HTL）. The CuOx/Cu buffer layer limits the operating current density obviously, while the brightness and efficiency are both enhanced greatly. The highest brightness of the optimized device is achieved to be 14 000 cd/m2 at current efficiency of 3 cd/A and bias voltage of 15 V, which is about 50% higher than that of the compared device without CuOJCu buffer layer. The highest efficiency is achieved to be 5.9 cd/A at 11.6 V with 3 400 cd/m^2, which is almost twice as high as that of the compared device.

Optimization and degradation of rubrene/C_(70) heterojunction solar cells

Small molecule organic solar cells （OSCs） with the structure of indium tin oxide （1TO）/molybdenum trioxide （MOO3） （5 nm）/rubrene （x nm）/fullerene （C70） （y nm）/2, 9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline （BCP） （6 nm）/aluminum （A1） （150 nm） are fabricated. The thickness of active layer for the devices is investigated in details. The results show that the optimum thicknesses of rubrene layer and C70 layer are 30 nm and 25 nm, respectively. The degradation of the device is also investigated. The result indicates that the open-circuit voltage （Voo） does not change, while the short-circuit current density （Jsc）, fill factor （FF） and power conversion efficiency （PCE） decrease continuously with time. The degradation can be attributed to the oxygen in ambient diffusing and infiltrating into the active materials and reacting with C70 in cells, which can result in the increase of interfacial series resistance.

Photovoltaic properties of ferroelectric solar cells based on polycrystalline BiFeO_3 films sputtered on indium tin oxide substrates

To study the ferroelectric photovoltaic effect based on polycrystalline films, preparation of high-quality polycrystalline films with low leakage and high remnant polarization is essential. Polycrystalline BiFeO3 （BFO） thin films with extremely large remnant polarization （2Pr = 180 ~aC/cm2） were successfully deposited on glass substrates coated with indium tin oxide using a modified radio frequency magnetron sputtering method. Symmetric and asymmetric cells were constructed to investigate the ferroelectric photovoltaic effect in order to understand the relationship between polarization and photovoltaic response. All examined cells showed polarization-induced photovoltaic effect. Our findings also showed that the ferroelectric photovoltaic effect is highly dependent on the material used for the top electrode and the thickness of the polycrystalline film.

Electrochemical co-deposition of reduced graphene oxide-gold nanocomposite on an ITO substrate and its application in the detection of dopamine

The simultaneous deposition of rGO and gold nano structures has been achieved by electrodeposition from mixed solutions containing graphene oxide(GO)and a gold precursor.Scanning electron microscope(SEM),Raman spectroscopy and atomic force microscopy(AFM)have been employed to reveal the morphology,uniformity and practical stability of the nanocomposite films on the indium tin oxide(ITO)substrate.The AFM data showed heights of tens of nanometers of the nanocomposite,suggesting that multilayers of rGO with gold nanoparticles had been formed as a result of the electrochemical co-deposition.Differential pulse voltammetry(DPV),as a widely used analytical technique,has been carried out on the rGO-Au/ITO electrode for the quantitative detection of dopamine(DA).The detection limit(S/N=3)for the determination of DA was evaluated as 0.6μM.

Preparation and characteristics of Nb-doped indium tin oxide thin films by RF magnetron sputtering

Niobium-doped indium tin oxide （ITO：Nb） thin films are fabricated on glass substrates by radio frequency （RF） magnetron sputtering at different temperatures. Structural, electrical and optical properties of the films are investigated using X-ray diffraction （XRD）, atomic force microscopy （AFM）, ultraviolet-visible （UV-VIS） spectroscopy and electrical measurements. XRD patterns show that the preferential orientation ofpolycrystalline structure changes from （400） to （222） crystal plane, and the crystallite size increases with the increase of substrate temperature. AFM analyses reveal that the film is very smooth at low temperature. The root mean square （RMS） roughness and the average roughness are 2.16 nm and 1.64 nm, respectively. The obtained lowest resistivity of the films is 1.2 × 10^4 Ω-cm, and the resistivity decreases with the increase of substrate temperature. The highest Hall mobility and carrier concentration are 16.5 cmVV.s and 1.88× 10^21 cm^-3, respectively. Band gap energy of the films depends on substrate temperature, which is varied from 3.49 eV to 3.63 eV.

Gold nanoparticles attached NH^(2+) ion implantation-modified indium tin oxide electrode:Characterization and electrochemical studies

An NH2+ ion implantation-modified indium tin oxide film was prepared and the implantation of amino groups on the indium tin oxide substrate was verified by X-ray photoelectron spectroscopy analysis.The gold nanoparticles attached surface could be obtained by self-assembly of different sized colloidal gold nanoparticles onto the NH2+ ion implantation-modified indium tin oxide surface.By scanning electron microscopy and electrochemical techniques,the as-prepared AuNPs attached NH2+ ion implantation-modified indium tin oxide electrode was characterized and compared with bare indium tin oxide electrode.Using a [Fe(CN)6]3 /[Fe(CN)6]4 redox probe,the increasingly facile heterogeneous electron transfer kinetics resulting from the attached gold nanoparticle arrays was observed.The gold nanoparticle arrays exhibited high catalytic activity toward the electro-oxidation of nitric oxide,which could provide electroanalytical application for nitric oxide sensing.

Surface modification of indium tin oxide by oxygen plasma immersion ion implantation

Organic electroluminescent device,also known as organic light-emitting diode (OLED),is a kind of solid state light emitting device by carrier injection which can directly transform electrical energy into luminous energy.Due to its low operating voltage,low energy consumption,high brightness,flexibility in the choice of materials and easy realization of full color display,OLED is the potential material both in the display and illumination fields.However,there is much scope to improve the efficiency,lifetime,and reduce the cost in mass production before OLEDs can replace traditional technology in some application fields.In this work,we report the oxygen plasma immersion ion implantation (PIII) to improve the surface oxygen ratio of ITO films for further increase of surface work function above the common treatment of O2 inductively coupled plasma (ICP).The ratio of oxygen content at the surface layer was improved to be much higher than by O2 ICP treatment.A further surface work function relative increase of 0.4e V above OICP sample and 0.4 eV above the as-prepared sample can be estimated by the peak relative shift in the X-ray photoelectron spectroscopy (XPS) diagram.Moreover,the XPS characterization was carried out at least 50 h after the PIII implantation to indicate that the surface modifying effects are stable.The variations of transparency and conductivity of the PIII treated ITO samples can be neglected.

Transient photovoltage and photoluminescence study of exciton dissociation at indium tin oxide/pentacene interface

The exciton dissociation at ITO/pentacene interface is studied by means of transient photovoltage measurement.Opposite to ITO/NPB,ITO/CuPc or ITO/C60 interface where polarity change of transient photovoltage is observed,no interfacial dissociation is found at room temperature,which indicates a lack of Frenkel excitons in pentacene.Temperature-dependent photoluminescence (PL) is investigated.More like the behavior of inorganic semiconductors,the integrated PL intensity exhibits monotonic decrease with increasing temperature.A nonradiative path with characteristic activation energy of 8 meV is found to dominate at room temperature.The PL measurement also indicates that like in inorganic semiconductors,other types of excitation,for example,free carriers,could be responsible for the photoelectric processes.

Effects of indium doping concentration on the morphology and electrical properties of one-dimensional SnO_2 nanostructures prepared by a molten salt method

In this paper,indium doped SnO2 nanorods and nanowires have been prepared by the molten salt method,and the effects of indium doping concentration on the morphology and electrical properties of one-dimensional(1D) SnO2 nanostructures have been studied.It is found that indium doping concentration can affect the epitaxial growth,morphology and the electrical conductance of 1D SnO2 nanostructures.It is also found that the element made by using 6 mol% indium doped SnO2 nanorods responds to nitrogen gas.

Enhancement of light output powers of GaN-based light emitting diodes with textured indium tin oxide transparent layer by using corrosive liquid

In order to promote the light output powers of GaN-based light emitting diodes (LEDs), two kinds of novel corrosive liquidshave been developed in this paper to roughen the surface of the indium tin oxide (ITO) current spreading layer of LEDs. As aresult, the textured transparent ITO layer greatly enhanced the external quantum efficiency of the LEDs. Provided that a wafersample was dipped in a kind of corrosive liquid developed by us for only about 60 s, the light output powers of the LEDs canbe promoted by 24.7%, compared with conventional GaN-based LEDs. It is obvious that the presented method is simple, rapidand cost-effective.

The effect of dispersion of TiO_2 nanoparticles on preparation of flexible dye-sensitized photoanodes

Generally, nanoparticles are easy to aggregate due to their nano sizes, which influence the physical and chemical properties. In this work, a dispersion treatment of the TiO2 nanoparticles with different average sizes was employed to improve the disper- sion of TiO2 nanoparticles, in order to prepare flexible photoanodes for dye-sensitized solar cells （DSCs） with novel photovol- talc properties at a low temperature. The effects of dispersion treatment on the dispersion of TiO2 nanoparticles, including the viscosities of the binder-free TiO2 paste, the morphologies and textural properties of nanoparticle-TiO2 films, and the photo- voltaic properties of the flexible DSCs, were investigated. Flexible indium-tin oxide （ITO）-coated polyethylene naphthalate （PEN） substrates with sputter deposited Pt were employed as the transparent flexible counter electrodes. A short-circuit photo- current density of 9.62 mA·cm^-2, an open-circuit voltage of 0.757 V, a fill factor of 0.589 and an overall light-to-energy con- version efficiency of 4.29% for the flexible DSCs under AM1.5 illumination of 100 mW·cm^-2 were obtained with dispersion treatment. A 30.8% increment of the energy conversion efficiency for DSCs made by dispersion treatment was obtained com- pared with that made without dispersion treatment.