Terry Alford

• Roswell Park Comprehensive Cancer Center

One-step-antisolvent treatment is one of the most viable methods to increase the nucleation density for fabricating high-quality triple cation perovskite films (TC-PVS). The active triple cation perovskite layer plays a significant role in influencing the solar cell’s efficiency. However, achieving a crack-free perovskite layer is still very challe...

In perovskite solar cells, the active perovskite layer is crucial in influencing the solar cell's efficiency. Crack-free perovskite films with enlarged grain size are essential for a highly efficient solar cell. Triple-cation perovskite (TC-PVS) mainly relies on solvent–antisolvent engineering for achieving good crystal growth and enlarged grains....

Inverted-structure perovskite devices with PEDOT and PEDOT/CuI as hole transport layers (HTLs) were prepared on Glass/ITO substrates. Surface morphology observation of the CuI revealed that the CuI grew on PEDOT in island mode. A concentration of 20 mg/ml was necessary for continuous CuI formation on the PEDOT. Optimization of the annealing time an...

The efficiency of more than 25% in organic-inorganic hybrid perovskite solar cells has made them very attractive in the pursuit of cheaper alternatives to Si-based devices. However, the stability of the perovskite solar cells was challenging, given their high susceptibility to moisture. Very few reports have emerged in this regard that investigated...

In this investigation, urea (NH2CONH2) was added into the perovskite precursor solution with Pb(CH3COO)3 as precursor. The effects of the urea content in the solution on the crystallization dynamics and the orientation of the perovskite films, and their photovoltaic properties were investigated. The results showed that the optimal annealing duratio...

In this study, we reported a low-temperature, one-step solution process to fabricate perovskite solar cells using dehydrated lead acetate as the lead source. These perovskite films were aged at 200 s before thermal annealing at 90 °C for 5 min. Uniform perovskite films with lesser pinholes were obtained by this technique. The inverted planar (n-i-p...

In this study of the fabricated perovskite solar cells, flowing nitrogen is introduced during the spin coating of the precursor to remove the solvent vapor. The precursor is then aged prior to the anneal to obtain a pinhole-free perovskite film. Both the nitrogen flow and precursor aging methods resulted in improved film quality. The phase composit...

Perovskite solar cells have evolved significantly since their inception. However, stability is still a major concern. We fabricated devices using a glass/ITO/PEDOT:PSS/MAPbI3/PCBM/Ag device configuration. Devices fabricated using the Pb-acetate precursors showed an efficiency of 13%. This work reports the effect of adding excess lead to the precurs...

The existence of the Schottky barriers at the top and bottom electrodes of the ferroelectric thin film sandwich structure makes it difficult to separate and collect electron-hole pairs, thus limiting the enhancement of the photocurrent. In this paper, Pb(Zr,Ti)O3 (PZT) and composite structure of PZT/CuO films are prepared by a sol-gel method and th...

The influence of the content of trifluoroacetate (TFA), in the precursor solution, on the critical current density (Jc) of YBa²Cu³O7-x (YBCO) superconducting films was investigated. We found that a TFA/Ba ratio of 0.68 is optimal to obtain high-performance YBCO films. Using this optimal solution, we then developed an ultraviolet (UV) light soaking...

The stability of perovskite solar cells exposed to prolonged solar irradiation is a major concern that has not been thoroughly investigated in the past. In this investigation, devices fabricated with the architecture, glass/ITO/PEDOT:PSS/MAPbI3/PCBM/Ag using Pb acetate as a source material, were found to operate with an efficiency of about 13%. Add...

Transparent composite electrodes (TCE), TiO2/Ag/TiO2 (TAgT), have been demonstrated as a promising alternative of indium tin oxide (ITO) in organic solar cell application. TiO2/Ag/TiO2 have been incorporated into bulk heterojunction organic solar cells (OSCs) to replace ITO as the anode. Two different hole transfer layers (HTL), poly(3,4-ethylenedi...

A novel ultraviolet photochemical method was used to prepare TiO2 resistive-switching films. Amorphous TiO2 films were formed on flexible indium-tin oxide (ITO) coated polyethylene terephthalate (PET) substrates by deep ultraviolet irradiation at 150 °C. A Pt/TiO2/ITO/PET device was then fabricated to investigate bipolar resistive switching of the...

The ease of fabrication and wide application of printed microelectronics are driving advances in reactive inks. The long-term performance of structures printed using reactive ink is important for their application in microelectronics. In this study, silver lines are printed with low-temperature, self-reducing, silver-diamine based ink. The electrom...

Silver-chalcogenide glass flexible sensors were tested to study the impact of physical design parameters on the performance characteristics of the sensors in response to ionizing radiation. Results show that by changing lateral spacing between adjacent electrodes, the limit of detection and dynamic range can be regulated. Likewise, by changing the...

Recent interest in indium-free transparent composite-electrodes (TCEs) has motivated theoretical and experimental efforts to better understand and enhance their electrical and optical properties. Various tools have been developed to calculate the optical transmittance of multilayer thin-film structures based on the transfer-matrix method. However,...

Amorphous indium gallium zinc oxides (IGZO) of 100 nm thickness were deposited onto glass substrates by sputtering at room temperature. The films were subsequently annealed in air, vacuum, forming gas and O2 environments by both conventional and microwave methods. The optical and electrical properties of the as-deposited and annealed samples were m...

The compatibility of gold with underlying substrate materials is important for device performance and reliability. Gold nanolayers of various thicknesses (4–14 nm) are deposited onto different substrates (glass and flexible substrate) by sputtering at room temperature. The flexible substrate used in the study was polyethylene napthalate (PEN). The...

The interest in indium-free transparent composite electrode (TCE), a thin metal layer embedded between two transparent metal oxide (TMO) layers resulting in TMO/metal/TMO composite structure, has grown recently with the advent of their high figures of merit and its potential application in photovoltaic applications. However, most of the work to dat...

Many sustainability issues arise during the manufacturing processes that are currently used for solar cells. Solar energy is a renewable energy source that is independent of the earth's resources, and it is therefore important for the development of more sustainable technologies. Microwave annealing (MW) has been proposed as a technically feasible...

Advanced printing techniques include innovative and/or integrated processes that are used to produce an object with enhanced functionality and with a wide range of applications. This is done by realizing printing of functional materials such as ink, paste, polymer, ceramic powder, and organic materials. Unlike conventional manufacturing methods, a...

Many sustainability issues arise during the manufacturing processes that are currently used for solar cells. Solar energy is a renewable energy source that is independent of the earth’s resources, and it is therefore important for the development of more sustainable technologies. Microwave annealing (MW) has been proposed as a technically feasible...

In this paper, previous work on chalcogenide-glass (ChG)-based radiation sensors is extended to include the effects of mechanical strain and temperature stress on sensors formed on a flexible polymer substrate. We demonstrate the feasibility of producing inexpensive flexible radiation sensors, which utilize radiation-induced migration of Ag+ ions i...

In this paper, the optoelectronic properties and morphological features of indium-free ZnO/Ag/MoOx electrodes deposited by in situ combination of RF and DC sputtering at room temperature for low-cost organic photovoltaics has been discussed. The transparent composite electrode (ZnO/Ag/MoOx) was optimized by inspecting the formation of a continuous...

Highly transparent conductive composite electrodes made of multilayer of TiO2 and Cu (TiO2/Cu/TiO2) thin films (30/3-9/30 nm thick) are deposited onto flexible substrates at room temperature. The micro-structural, optical and electrical properties of the multilayer are studied with the use of atomic force microscopy, uv-visible spectrophotometry an...

In recent years, a substantial amount of research has been focused on identifying suitable interfacial layers in organic light-emitting diodes and organic solar cells which has efficient charge transport properties. In this work, a very thin layer of AgOx is deposited on top of the ITO layer along with PEDOT:PSS and is observed that the solar cells...

The failure mechanisms arising from the instability in operation of indium gallium zinc oxide based thin film transistors (TFTs) upon prolonged real application stresses (bias and illumination) have been extensively studied and reported. Positive and negative gate bias conditions, along with high photonic energy wavelengths within visible light spe...

Rapid processing and reduced end-of-range diffusion result from susceptor-assisted microwave (MW) annealing, making this technique an efficient processing alternative for electrically activating dopants within ion-implanted semiconductors. Sheet resistance and Hall measurements provide evidence of electrical activation. Susceptor-assisted MW anneal...

For the first time it is reported that nitrogen-doped titanium oxide with light annealing can improve the device performance by 300% when acting as an interfacial layer between CdSe quantum dot/poly-3-hexylthiophene and the cathode in the photovoltaic devices. Substitutional N doping with a concentration of 1.2 at.% was found by X-ray photoelectron...

In this letter, we demonstrate the stability of Te-Ti thin films as a barrier against Cu after thermal annealing. Te-Ti chalcogenide glass films of composition Te0.20Ti0.70O0.10. and thickness 35 nm are annealed in vacuum for up to 30 min at several temperatures up to 600 degrees C. Four-point-probe analysis results show that the Cu layers are stab...

Susceptor-assisted microwave annealing enables effective dopant activation, at low temperatures, in ion-implanted Si. Given similar thermal budgets for microwave annealing and rapid thermal annealing (RTA), sheet resistances of microwave annealed Si, with either B+ or P+ implants, are lower than the values obtained using RTA. The fraction of dopant...

Yttrium doped zinc oxide (ZnO) nanowires prepared on seedless indium tin oxide (ITO) substrates were used for nanostructured bulk heterojunction organic solar cells (OSCs). Without patterning by a mask, the optimized areal density of ZnO nanowires decreased the reflection of incident light impinging upon the substrate by more than 50%, resulting in...

We report on the electrical and optical properties of ZnO/Ag/MoO3 (ZAM) multilayer electrodes deposited directly on glass substrates by a combination of radio frequency (RF) and direct current (DC) sputtering for bulk-heterojunction organic solar cells (OSCs). Compared to indium tin oxide (ITO) electrodes showing 20 Ω/sq, the transparent composite...

Herein the synthesis of Cu 3 Ge films by exposing Cu-Ge alloy films to microwave radiation is reported. It is shown that microwave radiation led to the formation of copper germanide at temperatures ca. 80 °C. The electrical properties of the Cu 3 Ge films are presented and compared for various annealing times. X-ray diffraction shows that the Cu 3...

The effect of gamma radiation on low-temperature fabricated indium-zinc-oxide (IZO) thin-film transistors (TFTs) has been investigated. A negative turn-on voltage shift and sub-threshold swing degradation are observed after irradiation with a total dose of 1.7 Mrads from Co-60. There is an increase in electron mobility from 2.8 to 8.8 cm(2)/V-s aft...

Silver doped cupric oxide thin films are prepared on polyethylene naphthalate (flexible polymer) substrates. Thin films Ag-doped CuO are deposited on the substrate by co-sputtering followed by microwave assisted oxidation of the metal films. The low temperature tolerance of the polymer substrates led to the search for innovative low temperature pro...

Multilayer structures of TiO2/Ag/TiO2 have been deposited onto flexible substrates by room temperature sputtering to develop indium-free transparent composite electrodes. The effect of Ag thicknesses on optical and electrical properties and the mechanism of conduction have been discussed. The critical thickness (tc) of Ag mid-layer to form a contin...

Stability testing of indium-zinc oxide under extreme conditions is necessary before the metal oxide can be deemed a reliable alternative to a-Si as channel layer in thin film transistors (TFTs). In this paper, we apply thermal stress under positive and negative gate bias stress creating practical application conditions. This stress scenario gives g...

The fabrication of a thin film optoelectronic device involves the exposure of the transparent conductive oxide (TCO) to a high process temperature. Indium gallium zinc oxide (InGaZnO 4 or IGZO) is a well known TCO with high optical transparency, moderate conductivity and high mobility. However, its electrical properties deteriorate after subsequent...

Multilayer structures of TiO2/Au/TiO2 have been deposited onto flexible substrates by room temperature sputtering to develop indium-free transparent composite electrodes (TCEs). The effect of Au thicknesses on optical, electrical properties and the mechanism of conduction have been discussed. The electrical conductivity of the TCEs is solely contri...

1 557/op 013 0.1 l.2 . ABSTRACT Highly transparent composite electrodes made of multilayers of In-and Ga-doped ZnO and Cu (IGZO/Cu/IGZO) thin films (30/3-9/30 nm thick) are deposited onto flexible substrates at room temperature and by using radio frequency magnetron sputtering. The effect of Cu thickness on the electrical and optical properties of...

The effects of Cu content on the electrical and structural properties of Ag-Cu thin films were studied before and after microwave processing. Copper was chosen as the alloying element because of its low solubility in Ag, which enables it to segregate at the surface. After microwave annealing, enhanced electrical and structural properties were obser...

We have investigated the optical properties of sputter-deposited silver-copper alloy thin films on silicon substrates at room temperature. We found that alloying copper with silver can significantly improve the metal’s surface morphology, keeping its infrared reflectivity same as that of pure silver film. However at the same time, it worsens in the...

Thin films of amorphous indium gallium zinc oxide with high transmittance were deposited at room temperature onto flexible polymer substrates. Postdeposition anneals were performed at low temperatures in different ambients to obtain films with one of the highest transmittance and mobility values reported in the literature. As-deposited and postanne...

This study reports the operational instability and failure causing defect mechanisms of indium gallium zinc oxides based thin film transistors (TFTs) under practical, combined bias and illumination stress conditions. The effect of the illumination stress with light source of different wavelengths (410 nm, 467 nm, 532 nm, and 632 nm) has been explai...

This study discusses thermally activated defects in the channel layer of indium zinc oxide (IZO) thin film transistors (TFTs) under electrical and thermal stress resembling practical stress scenarios. Operating temperatures of 20, 50, and 80 degrees C have been chosen to establish a relation between temperature and failure mechanism. With increasin...

This research reports the performance of low temperature fabricated indium zinc oxide (IZO) TFTs under the influence of gamma radiation. Irradiation with a dose of 1.7 Mrads resulted in a negative threshold voltage shift and degradation in the subthreshold swing. The electron mobility however increased on gamma exposure from 2.8 to 8.8 cm(2)/V-s. T...

Multiple walled carbon nanotubes have been incorporated into yttrium-doped zinc oxide (YZO) films through sol–gel method. Sol–gel process is used since it is an inexpensive means of thin film deposition when compared to the more expensive and time consuming techniques like RF sputtering. The structural, electrical and optical properties of the YZO...

In the present study, thin films of binary Ag–Cu alloys with different Cu content were prepared by a cosputtering technique and then annealed by microwave heating. The metallographic and electrical properties of the thin films were observed experimentally. It was found that the electrical performance of Ag–Cu thin films enhanced after microwave pro...

This investigation elucidates the influence of standalone-bias stress and standalone-illumination stress, and their combinatory effect on indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs). Each phenomenon associated with illumination (wavelengths of 410, 467, 532 and 632 nm) and bias (Vg = ±20 V; Vd = 0, 20 V) stresses is categorized in...

Copper (I) oxide (Cu2O) forms an encapsulation layer after annealing Ag–17 at% Cu alloy thin films inside a microwave cavity. The maximum temperature reached during this process is 70 °C which makes microwaves an efficient low temperature processing tool for flexible electronics. Rutherford backscattering spectrometry is used to study the encapsula...

Different multilayer structures of Nb{sub 2}O{sub 5}/Ag/Nb{sub 2}O{sub 5} have been deposited onto flexible substrates by sputtering at room temperature to develop an indium free transparent composite electrode. The effect of Ag thickness on the electrical and optical properties of the multilayer stack has been studied in accordance with the Ag mor...

We report on the enhanced performance of hybrid photovoltaic devices consisting of poly(3-hexylthiophene), (6,6)-phenyl C61 butyric acid methyl ester, and zinc oxide (ZnO) nanorod arrays grown on seedless indium tin oxide (ITO) glass in aqueous zinc chloride solution. Introduction of optimized-length ZnO nanorod arrays between hole injection and IT...

Wafer segmentation is investigated as a method to introduce flexibility to crystalline photovoltaics. A proof-of-concept flexible device was fabricated from an InP/InGaAsP multiple-quantum-well solar cell by integrating the device wafer with a polymer substrate via an electrically-conductive adhesive and subsequently fracturing the wafer along para...

A transparent conductive electrode of mixed titanium dioxide (TiO2−x)–indium tin oxide (ITO) with an overall reduction in the use of indium metal is demonstrated. When used in organic photovoltaic devices based on bulk heterojunction photoactive layer of poly (3-hexylthiophene) and [6,6]-phenyl C61 butyric acid methyl ester, a power conversion effi...

Microwave annealing of arsenic-doped silicon was employed to achieve nearly complete dopant activation and repair of damage caused by ion implantation. Analysis of Rutherford backscattering spectra suggested that volumetric heating from microwaves can repair ion-implantation damage. Secondary ion mass spectroscopy depth profiling revealed that even...

In this study, we have characterized the microstructure, resistivity, and dynamic deformation behavior of Cu/Ru/SiO2 and Cu/SiO2 samples under scratch loading conditions. Cu/Ru/SiO2 samples showed higher elastic recovery and hardness when compared to the Cu/SiO2 samples. In the case of Cu/Ru/SiO2 samples, Ru acts as a glue layer between the Cu and...

In this study, we investigated the possibility of fabricating flexible single-crystal Si-Pd diodes on polymer substrates using silver-filled conductive tape or epoxy. This simple technique mitigates the complexity of process-intensive metal-bonding schemes to achieve backside electrical contacts on semiconductor devices. The performance of such dev...

This study reports the influence of electrical and mechanical stresses on indium zinc oxide (IZO) thin film transistors (TFTs).The deformation is introduced by mounting the samples on cylindrical structures of varying radii creating tensile or compressive strains. The mechanical stresses are parallel and perpendicular to the length of the channel l...

It is important for nanoscale transistors to have abrupt junctions, which are difficult to achieve via high-temperature anneals of implanted semiconductor layers due to undesired dopant diffusion. The use of a single-frequency microwave cavity applicator, along with a SiC-Alumina susceptor/assistor, is suggested as an alternative postimplantation p...

The increasing need for quicker and more efficient processing techniques motivates the study of the use of a single frequency applicator microwave cavity, along with an alumina-coated SiC susceptor, as an alternative to current post-implantation processing. The extent of Si recrystallization and repair of the damage caused by arsenic implantation i...

Amorphous indium gallium zinc oxide (a-IGZO) thin films of the highest transmittance reported in literature were initially deposited onto flexible polymer substrates at room temperature. The films were annealed in vacuum, air, and oxygen to enhance their electrical and optical performances. Electrical and optical characterizations were done before...

The double-flip transfer of indium phosphide (InP) based transistors onto plastic flexible substrates was demonstrated. Modulation doped field effect transistor layers, epitaxially grown on InP bulk substrates, were transferred onto sapphire using a masked ion-cutting process. Following layer transfer, transistors were fabricated at low temperature...

Hydrogenated amorphous silicon (a-Si:H) thin-film transistors (TFTs) are widely used as controlling devices for picture pixels in liquid crystal displays. In addition to flat panel display applications, a significant research effort focuses on the extension of this technology to circuitry on flexible substrates to build flexible sensor systems. Thi...

The change in electrical characteristics of a-Si:H thin-film transistors (TFTs) was determined in the presence of electrical gate bias stress, gamma radiation, and both simultaneously, simulating the harsh environment of space. Multiple TFTs were tested under each condition, and the current-voltage characteristics were measured. The results show th...

We report the epitaxial growth of sol–gel TiO2 films by using ion-irradiation enhanced synthesis. Our present study shows that the ion-beam process can provide highly crystalline TiO2 even at 350°C. Nuclear energy deposition at amorphous/crystalline interface plays a dominant role in the epitaxial growth of the films at the reduced temperature via...

We report on the properties of ZnO:F films deposited by RF sputtering on polyethylene naphthalate (PEN) substrates and compared them with films deposited on glass. Detailed and systematic investigations of various properties of films were deposited on PEN substrates were carried out as functions of thickness and annealing ambient. The films were de...

In this letter, we report the effects of electromechanical and mechanical strain on amorphous ZIO thin-film transistors (TFTs), deformed on cylindrical surfaces of varying radii for varying time spans. The TFTs were fabricated on island structures on polyethylene napthalate and subjected to both tensile and compressive stress, parallel and perpendi...

The texture in polycrystalline Ag thin films prepared by e-beam evaporation has been characterized by an x-ray diffraction technique as a function of underlayers and encapsulation temperatures. The Ag films deposited on Ti layers showed a strong <111> fiber texture with a fiber axis parallel to the film normal, whereas an almost random orientation...

Transmission electron microscopy (TEM) in both cross sectional and plan view is used to study the effect of annealing Ag-Ti bilayers deposited on SiO2/Si substrates in an NH3 ambient. The resulting structure, texture and grain size are investigated. Comparisons are made between films annealed at 400, 500 and 600 °C. Silver films show increasingly s...

Thin heteroepitaxial films of Si1-x-yGexCy have been grown on (100)Si substrates using atmospheric pressure chemical vapor deposition at 550 and 700°C. The crystallinity, composition and microstructure of the SiGeC films were characterized using Rutherford backscattering spectrometry (ion channeling), secondary-ion-mass-spectrometry and cross-secti...

Single crystal Si0.63Ge0.36C0.01 and amorphous Si0.65Ge0.27C0.08 layers have been oxidized in a wet ambient at 700 °C and 900 °C. The oxide growth has been studied using Rutherford backscattering spectrometry and transmission electron microscopy. A reference sample of Si0.63Ge0.37 was also oxidized in order to determine the influence of C on the ox...

Shallow contact metallization of SiGeC was studied in anticipation of this alloys use in low power applications. It has been shown that in the solid state reaction of Co on (100) Si, that Co is the moving species with proper annealing conditions. This prevents the formation of Kirkendal voiding in certain device structures. This work studies the Co...

A model is proposed to describe the temperature dependence of the aluminum oxynitride (AlxOyNz) diffusion barrier formation during a silver self-encapsulation process. These barrier layers form in the temperature range of 500-725 °C during anneals of the Ag/Al bilayers on oxidized Si substrates in an ammonia ambient. Experimental results show that...

We investigate the nitridation of chromium films in an NH3 ambient at 500°C. Rutherford backscattering spectrometry using 2.0 MeV He2+ was utilized to determine the compositions of thick reacted layers and to provide calibration for the other techniques. In addition, analysis was performed using the 14N(α,α)14N resonance at 3.72 MeV in order to enh...

Polyimides prepared from oxydiphthalic anhydride and diamine precursors can be photosensitive. The thermal, mechanical, and dielectric properties of the polyimide films have been characterized with various techniques. The thermal decomposition temperature of the cured film is 520 °C, and the coefficient of thermal expansion is 20 × 10−6/°C. The pol...

Silicon oxide films ( > 1μm ) were grown at room-temperature after low-energy copper-ion implantation of Si(100) substrates. The structural properties of the silicon oxide layer and the implanted silicon were characterized by Rutherford backscattering spectrometry and transmission-electron microscopy. During room temperature oxidation a portion of...

Stress-induced cleavage was investigated as a method of transferring sizable areas of thin layers of silicon onto alternative substrates such as sapphire and flexible substrates. By bonding bulk silicon to a sapphire handle wafer using the polymer SU-8, an ultrathin layer of silicon can be transferred from the donor substrate onto the sapphire via...

The stress state of evaporated Ag films prepared on Ti underlayers before and after encapsulation process has been studied by x-ray diffraction using a “sin2ψ” technique. A low tensile stress of approximately 61 MPa was measured in the as-deposited Ag films. The stress was caused by nonequilibrium growth during film deposition and resulted in a lat...

ZnO/Au/ZnO (ZAZ) electrodes grown on flexible PEN substrates were evaluated as transparent electrodes for organic light-emitting devices (OLEDs). OLEDs fabricated with the ZAZ electrodes showed reduced leakage in contrast to control OLEDs on ITO and reduced ohmic losses at high current densities. At a luminance of 25000 cd/m2, the lum/W efficiency...

Transparent conducting ZnO/Au/ZnO thin film structures were grown by the magnetron sputtering technique on flexible polymer substrates. These films displayed a seven orders of magnitude drop in resistivity (200 to 5.2×10-5 Ω-cm) upon increase of the Au layer thickness from 0 nm to 12 nm. The sheet resistance also showed a substantial decrease to a...

For the benefit of reducing capacitance in multilevel interconnect technology, low-k dielectric HSQ (hydrogen silsesquioxane) has been used as a gapfill material in Al-metallization- based non-etchback embedded scheme. The vias are consequently fabricated through the HSQ layer followed by W plug deposition. In order to reduce the extent of via pois...

HSQ (hydrogen silsesquioxane) is one of the promising low-k materials used in VLSI technology as an intra-metal dielectric to reduce capacitance-related issues. Like any other dielectrics, the integration of HSQ in multilevel interconnect schemes has been of considerable importance. In this study, the compatibility of HSQ with different nitride bar...

Samples of Si1-x-YGexCy were analyzed with a triple axis high resolution x-ray diffractometer to produce reciprocal space maps. Films with compositions of approximately Si0.77Ge0.20C0.01 vvith thicknesses ranging from 120 nm to 750 nm were found to be pseudomorphic with a tetragonal distortion, εT, near 1%. The tetragonal distortion in pseudomorphi...

Encapsulated Ag(Ti) films on oxidized silicon were obtained by nitridation of Ag(19 at.% Ti) alloys in NH3 at temperatures between 400-700°C for various times. Upon annealing Ti segregates to the surface and alloy/SiO2 interface to form a TiN(O) surface layer and a TiO/Ti5Si3 interfacial bilayer structure. Resistivity values of 2.5 μΩ-cm were measu...

This work investigates the mechanical properties of indium tin oxide deposited on polyethylene napthalate substrates by rf sputtering method as a function of deposition conditions, including rf power, substrate temperature, and substrate treatment. X-ray diffraction analysis, Rutherford backscattering spectrometry and mechanical bending analysis ar...

Cu(Ti 27 at. %) and Cu(Cr 26 at. %) codeposited on silicon dioxide substrates were annealed in a flowing NH3 ambient at 400 - 600°C for 30 min. The Ti segregates to both the surface to form a TiN(O) layer and to the alloy/SiO2 interface to form a Ti-oxide/Ti-silicide bilayer. The Cr seems to migrate only to the free surface to form a CrNx layer. A...

We studied interfacial phase formation between copper and copper-alloy films on SiO2 in order to understand how to improve adhesion. CuCr and CuTi alloy and bilayer films on SiO2 were annealed from 400-600°C for 30 min in an N2 + H2 (5%) ambient. The bilayer systems exhibited refractory metal migration from the interface to the surface where they o...

Cu(90 nm)/Ti(20 nm) bilayers and Cu(Ti 27 at.%) alloy films were deposited on SiO2 and annealed in an NH3 ambient at temperatures 400–700° C for 30 min. During annealing Ti segregated to both the free surface and the alloy/SiO2 interface. At the surface Ti reacted with NH3 to form TiN, whereas at the interface the Ti reacted with the SiO2 to form a...

The use of ion-beam techniques to enhance selected properties of bioactive materials, such as the adhesion of hydroxylapatite (HA) coatings on titanium-based substrates has been investigated. In this study, very thin HA films on titanium substrates were created by pulsed laser deposition techniques. Ion irradiations were carried out using 260-keV a...