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A study was conducted to analyze maskless laser patterning of indium tin oxide thin films for flat panel display applications as a function of wavelength. Different harmonics of a diode-pumped Q-switched Nd:YLF laser were utilized. Results indicated that the absorption of the ultraviolet laser light by the glass substrate promotes the residue-free removal of the indium tin oxide film.

The syntheses and characterization of four In-thiolates are presented. The scheme involves the electrochemical oxidation of anodic indium metal in an acetonitrile solution of phosphinothiol ligands. Structural analysis showed that all four In-thiols exhibited six-coordinate geometries based on (InS3P3), (InS3P2O) and (InS4P2) cores. The In-P bond distances were found to be anomalously long, as a result of steric crowding.

The spatial and temperature dependence of the photoluminescence (PL) in a high quality bulk layer of InGaAs lattice matched to InP using the microluminescence based surface scan technique were investigated. It was shown that the PL spatial distribution is strongly dependent upon the temperature. It was suggested that the behavior is mainly related to the temperature dependence of the bimolecular recombination coefficient. Narrow PL spatial profiles about the laser excitation spot were found at low temperatures.

Optical constants of hexagonal GaN, InN and AlN for perpendicular polarization were modeled. Model parameters were determined using the acceptance-probability-controlled simulated annealing method. The model used an adjustable broadening function instead of the conventional Lorentzian one. The broadening can vary over a range of functions with similar kernels. The relative error obtained for the real part of the index of refraction is below 2% for all three materials.

Research was conducted to examine the crystalline silicon p-n junction solar cells containing a high density of In impurities. The continuity equations for electrons, holes and defect levels and the numerical resolution of Poisson's equation generates the current-voltage curves for several impurity concentrations. Results demonstrate that an increase of the short-circuit current densities of up to 6 mA/cm2 can be derived with the highest In impurity concentration. However, this results in the reduction of the open-circuit voltage and of the energy conversion efficiency.

A study was conducted to analyze long range atomic ordering in InGaN films prepared by molecular beam epitaxy on A-plan sapphire. The films were prepared using a three-step process. The sapphire substrates were nitridated by exposing their surface to an electron cyclotron resonance nitrogen plasma at 800 degrees C. X-ray diffraction experiments were carried out on a four-circle, double crystal diffractometer. Experimental results indicated that the degree of ordering correlated with increases in growth rate.

The stereochemistry of the 1,2-addition of six allylindium reagents to 2- and 3-pyridinecarboxaldehyde and to glyoxylic acid was investigated to determine the course of diastereoselectivity in these coupling reactions. In addition, the competitive intramolecular/intermolecular chelation options that take place during the indium-induced additions under aqueous conditions were examined. Experimental results showed that the ring nitrogen is chelated to the indium atom in the aqueous environment and that there exists a crossover in stereoselectivity with respect to the use of 3-PyCHO.

The synthesis of various gamma-heteroatom-substituted allylindium reagents as well as their reactions with carbonyl compounds were investigated. To this end, the reaction conditions were modified and 1,3-dibromopropene was replaced with 3-bromo-1-iodopropene. Experimental results showed that two types of organoindium complexes, namely, gamma-bromoallylindium and allylic diindium reagents, were produced from the reaction of 1,3-dibromopropene with metallic indium. Gamma-alkoxy-allylindium reagents were synthesized by treating the corresponding gamma-alkoxyallyllithium with indium trichloride.

A study was conducted to analyze structural changes on sol-gel-determined indium oxide thin films resulting from ultraviolet irradiations. Results indicated that incoherent and coherent ultraviolet photons generated charge transfers from O(super 2-) to In(super 3+). Findings also showed that the irradiation of coherent ultraviolet beams from an ArF excimer laser was effective in the crystallization of indium oxide.

A study was conducted to analyze bond lengths in wurtzite and zinc-blende In(sub x)Ga(sub 1-x)N and Al(sub x)Ga(sub 1-x)N random alloys using valence force field simulations supporting large supercells. Experimental results showed that the cation-cation bond lengths supported distinct values in the alloy. In addition, the cation-related splitting of the bonds and broadening of the alloy were larger in InGaN alloys than in AlGaN alloys.

The structure of the hydrated gallium(III), chromium(III) and indium(III) ions was characterized in aqueous perchlorate and nitrate solutions by large-angle X-ray scattering and extended X-ray absorption fine structure methods. The metal-oxygen bond distance in the first hydration sphere of the metal ions was calculated by the same techniques. Experimental results showed that each of the the three ions coordinates six water molecules that are hydrogen bonded to two water molecules in a second hydration sphere.

The band structures and optical properties of strained multiple quantum wires were investigated using the effective bond-orbital model. The gallium1-xindiumxarsenide quantum wires grown by strain-induced lateral ordering were used in the experiment. It was found that the biaxial strain caused by the lattice mismatch between the gallium-rich and indium-rich areas is most dominant. The strain tends to increase the quantum confinement and enhance the anisotropy of the optical transitions.

The application of interfacial electronic states as local probes for the lateral confinement of single ultrathin indium arsenide (InAs) insertions in gallium arsenide (GaAs) was investigated. Deep and shallow electronic states at ultrathin insertions were analyzed by deep-level transient Fourier spectroscopy and capacitance-voltage measurements near the transition from layer-by-layer to three-dimensional growth. Experimental results showed that interfacial deep-level defects are suitable to probe the local characteristics of ultrathin InAs insertions.

Open-framework materials have possible applications as absorbents, solid-state electrolytes and ion exchangers. There have been many studies of alumino- and gallophosphates, but only a few indium phosphates are reported. An attempt was made to find suitable synthesis conditions to stabilize InPO(sub4).H(sub2)O, a monohydrate, determine its crystal structure and describe links between three indium phosphate binaries.

The rearrangement of substituted epoxides catalyzed by indium(III) chloride was investigated. A simple and efficient method in which aryl-substituted epoxides isomerize with complete regioselectivity to produce a single carbonyl complex via cleavage of benzylic aldehydes and ketones was proposed. Experimental results showed that indium(III) chloride exhibits a high level of efficiency in causing the rearrangement of epoxides to the corresponding carbonyl compounds in a very selective manner.

Complete active-space multiconfiguration self-consistent field (CASSCF) followed by multireference singles + doubles configuration interaction (MRSDCI) computations were conducted for the low-lying electronic states of In3Sb2, In2Sb3, In3Sb2+ and In2Sb3+. The atomization and adiabatic ionization potentials, including dipole moments and other properties for the electronic states of In3Sb2 and In2Sb3 were also computed.

Microscopic photoluminescence and x-ray topography were used to systematically examine the critical thickness of strained multi quantum wells (MQWs) grown by metalorganic molecular beam epitaxy (MOMBE) or metalorganic vapor phase epitaxy (MOVPE) and comprised of InAsP/inGaAsP. Three types of net strain-critical thickness curves were investigated: curves for compressive MOMBE-grown strained MQWs, curves for tensile MOMBE-grown strained MQWs and curves for compressive MOVPE-grown strained MQWs. The findings are discussed.

A toggle operation of 39-63.5 GHz without tuning has been achieved by a digital dynamic frequency divider (DFD). The DFD employs a pair of clocked inverters (CI's) with source-coupled FET logic (SCFL) and uses 0.1-[[micro]meter]-gate In AlAs/InGaAs/InP high electron-mobility transistors (HEMT's) of good uniformity and high performance. On a 2-in wafer, the frequency divider showed a maximum toggle frequency ([f.sub.tog, max]) of 59.1[+ or -]3.3 GHz and a fabrication yield of 89%. This is the highest operation frequency ever reported for a broad-band digital frequency divider. Comparison of the DFD and the static frequency divider (SFD) showed that the ratio of [f.sub.tog, max] for the DFD to that for the SFD is much higher than the value expected from the linear-response theory. The comparison also showed that the ratio of the measured [f.sub.tog max] for the DFD to that for the SFD is 1.7, in contrast with the value of two expected from the circuit simulation. Delay-time analysis revealed that this 15% decrease of the ratio is due to the transmission delay of interconnections and charging time for stray capacitance. Index Terms - Frequency conversion, digital integrated circuits, indium compounds, MODFET integrated circuits.

The properties and preparation of the group 13 elements gallium, indium and thallium and cuboidal complexes from the incomplete cuboidal [MO3S4(H2O)9]4+ were examined. The single cube [MO3InS4(H2O)12]5+ was quantitatively converted into a double cube. The double cubes were oxygen sensitive and were oxidized by hydrogen in hydrochloride solutions. The single cubes were less reactive in air and were only oxidized by hydrogen at higher levels.

The synthesis of In(NRR')3 (R = Ph or t-Bu, R' = SiMe3; R = t-bu, R' = SiHMe2), In(NRR')3L (R = t-bu, R' = SiHMe2, L = p-Me2Npy; R = R' = Ph, L = py; R = Me, R' = SiMe3, L = py or p-Me2Npy), Li(In(NPh2)3Cl) and Li(In(NMe(SiMe3))4) was examined. The objective of the study was to prepare chemical vapor deposition precursors for use in combination with ammonia to give InN. Of the new compounds, In(N(t-bu)(SiHMe2))3 is the most promising precursor candidate.

The indium thiocyanate electrochemical oscillator was examined in an experiment and by digital simulation based on independently determined rate variables. Digital simulation results showed that the characteristic features of the oscillations can be reproduced in the absence of additional model assumptions. The indium reaction in aqueous thiocyanate mixture can also be analyzed without the need for external resistance. In addition, measurements can be made on well-defined, easily renewable and highly reproducible mercury electrodes.

The monochlorides of indium and thallium were observed to react with ((tBuNP)2(tBuNLi*THF)2) under identical raction conditions to produce nonisostructural complexes. Thallium monochloride underwent a metathetical exchange to yield a dinuclear heterocube in which both metal atoms are brought into close, but nonbonding, contact by the bridging ligand. On the other hand, indium monochloride disproportionated to produce a dimeric indium(II) complex with an unsupported indium-indium bond.

The incorporation of indium phosphide semiconductor inside MCM-41 materials via metal organic chemical vapor deposition was studied using a range of analytical techniques. These include powder X-ray diffraction, solid-state NMR spectroscopy, high resolution transmission electron microscopy, nitrogen adsorption and UV/vis diffuse reflectance spectroscopy. The presence of large surface deposited indium phosphide particles and nanosized indium phosphide particles within the pores was indicated by line broadening in X-ray diffraction patterns, a result affirmed by high resolution transmission electron microscopy. Pore filling data were gleaned from nitrogen adsorption.

Experiments were conducted to describe a theoretical and empirical investigation of argon scattering off the surface of liquid indium. Liquid indium is a liquid metal with a low melting point and low vapor pressure. The structure and dynamics of liquid-vapor interface were examined. In addition, the energy and angular distributions of the scattered argon atoms were also analyzed. A discrepancy between the simulation and experimental results were observed. However, the results provide insights on the gas-liquid energy-transfer processes.

The chemical structure of indium (In)(super 0), In+ and In2+ in zeolite A and the sorption properties of sulfur into indium zeolites were examined. Elemental sulfur was exposed to completely indium-exchanged zeolite to achieve this end. Crystals of the zeolite were prepared and analyzed. The structure per unit cell was recorded at 8.75 indium atoms or ions distributed over six crystallographic sites per unit cell of In(sub 8-A).(In)0.75(S2). The indium ions farthest from the framework oxygens exhibited the smallest cationic charges.

Researchers used time-resolved reflectivity to monitor crystallization of amorphous tin-doped indium-oxide which had been deposited to a thickness of 110 nm by dc-magnetron sputtering. Results indicate that the amorphous to crystalline transformation process includes rapid nucleation in columns which are limited by voids through the film. Lateral seeding allows the grains to grow radially. The transformation process has an activation energy of around 0.67 eV.

Researchers measured the photoconductivity of rf-sputtered amorphous germanium thin films after doping with gallium and indium. Increases in gallium concentrations are accompanied by decreases in eta mu tau (HMT) down to a level 16 times lower than that in undoped samples. The HMT then increases, due to Ef crossing the midgap level, but later decreases again. Indium doping produces a montonic decrease in HMT for all levels of concentration.

Researchers used atomic force microscopy to study the effects of rapid thermal annealing on InP/GaAs heteroepitaxial layers. Study of the surface morphology revealed only negligible roughening beyond the etch pits caused by phosphorous loss which are visible under optical microscopy. The very small amount of extra roughening revealed under atomic force microscopy would not affect applications in devices, so optimization of annealing temperatures need relate only to the macroscopic pit formation.

Research was conducted to examine the interaction of indium(I) halides with bifunctional arylmercury derivatives and to show that the reaction of peri-dimercurated naphthalene compounds with indium(I) halides leads to the synthesis of novel indium-containing ring systems. Results suggest that the course of the reaction of polyfunctional organomercuric compounds with indium(I) halides is difficult to predict but permits the synthesis of novel systems.

The enhancement of electrical and structural properties of semi-insulating Fe-doped InP was demonstrated by thermal treatment, by either wafer or ingot annealing. Wafer annealing was found to be effective in not only the removal of the doping growth striations but also in the removal of microdefects in the matrix and those decorating the dislocations. An increase in resistivity also resulted for both treatments.

Ru(III)-derived acceptors were selected to compare the reduction reactions of In+ and Ti(III) oxidants with carbonyl functions. The discrepancy seen with the substitution of Cl- for ClO4- in the supporting electrolyte reflects the influence of specific medium on the rates of electron transfer between charged reactants. The slow conversion of the preponderant form of the carbonyl-substituted oxidant to a C(OH)2 species was shown by the initial [InI]-independent section of the mixed-order profiles.

An investigation of electrically active defects in p-InP by CH(sub.4):H(sub.2) from reactive ion etching (RIE) is discussed. The main defect, a donor with an energy level at E(sub.c) - 0.38eV, was passivated by hydrogen. Optical deep-level transient spectroscopy, Schottky barrier height measurements, and rapid thermal annealing were used to identify defects.

Periodically Si delta-doped InP grown by low-pressure organometallic vapor-phase epitaxy has been studied relative to electronic and optical properties. A broad band emission was seen for the periodic structures at energies higher than the InP band gap.

In2O3 thin films were prepared from an aqueous sol and organic solution. A study was then conducted on the aqueous sol's stability in relation to pH and indium concentrations. The thermal events that took place during sintering were examined using thermo-gravimetric and differential thermal analysis. Transmission electron microscopy, the four probe method, visible light spectrometry and x-ray diffractometry were used to study microstructure, electrical properties, optical properties and phase purity, respectively.

Material characteristics of various lattice-mismatched In(sub x)Ga(sub 1-x)As/InAs(sub y)P(sub 1-y) alloys grown on InP substrates were studied. The lattice constants and compositions were measured by x-ray diffraction and electron probe microanalysis. The quality of the grown layers was also examined. The dependence of the experimental measurements of band gap and lattice constant on material composition, measured by electron probe microanalysis, was contrasted against theoretical values.

The heteroepitaxial growth of indium formed at the interfaces between ZnO thin film and InP monocrystalline substrates were characterized by x-ray diffraction. Findings showed that the evolution of the degradation is regulated by the decomposition of close-packed InP(111) planes, while the polar character of these planes has a very significant function. Also, for all four employed orientations of InP substrates, In was observed to grow (101) on InP(111) planes. On an InP(111) interface plane, In crystallites can occur in six possible orientations.

The diffusion parameters of indium in silicon are examined. Systematic diffusion experiments in dry oxidizing ambients of temperature ranging from 800 to 1050 degrees C are performed utilizing silicon wafers implanted with indium. Findings reveal that the segregation coefficient of indium at the Si/SiO2 interface is similar to boron except that unlike boron, it decreases with increasing temperature. The validity of the extracted parameters is checked by comparing the simulated and measured secondary-ion-mass spectrometry profiles for indium implanted buried-channel p-channel metal-oxide-semiconductor field-effect-transistor.

The temperature- and magnetic field-dependence of the electron Hall mobility were measured in undoped n-type InSe and Er-doped InSe at temperatures of 10-340 K along with the transverse and longitudinal magnetoresistance effects. The results, which indicated that the erbium atoms are not electrically active, showed that the electrical conductivity of both samples lessens as the temperature increases for the temperature range 60-100 degrees Celsius.

A series of allyl bromides having an ethereal stereogenic substituent at C-2 were synthesized from methyl acrylate. These were coupled with a number of aldehydes under chromium(II) chloride-mediated conditions to produce syn-4-alkoxyalkan-1-ols in good yield and diastereoselectivity. The effect of changing the nature of the ethereal group and alkyl substituent on the diastereoselectivity of the reaction was also studied. Even when chromium(II) was replaced by indium, syn-4-alkoxyalkan-1-ols was also produced in good yield and diastereoselectivity.