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Industry-wide, the degradation and corrosion of steel infrastructure and the associated maintenance to prevent or mitigate this, poses a heavy environmental and operational burden across many industry segments. To address these challenges, ADNOC Group Technology, led by our Non-Metallic Steering Committee and ADNOC Upstream, in partnership with several selected specialist product companies, is deploying a range of innovative solutions as pilot trials within a holistic R&D program – which is aiming to transform our production and processing facilities, with a close focus on integrity management – and specifically we are assessing the deployment of non-metallic pipelines, storage and process vessels as well as downhole tubing and casing. Focusing specifically on flowlines and pipelines - traditional steel pipes used in the oil patch are burdensome to store, transport and install, as well as susceptible to degradation, corrosion-driven wall loss in challenging operational environments, such as those found Onshore and Offshore Abu Dhabi. This vulnerability results in increased operating risks as facilities mature, adding cost and time for inspection, maintenance and eventually - replacements that will lead to production deferrals or interruptions. A range of non-metallic pipeline technologies are being assessed and piloted in this program, including stand-alone extruded polymeric pipe and liners, Reinforced Thermoplastic Pipe (RTP) used Onshore and Offshore, specialized non-metallic flexible pipelines for Offshore including Thermoplastic Composite Pipe (TCP) and downhole tubulars. The methodology involves placing segments of RTP into live pipeline systems for a finite duration of operation – usually one year – and then removing sections to assess any degradation in performance, or capability of the RTP during that time. These test results will be the subject of a further publication at the end of this trial period. In this paper, we will focus on RTP piloting Onshore and specifically mention a unique trial in an ultra-sour gas field, where the technology has already delivered the required performance: safely transporting gas with levels of H2S up to 10% by volume. This trial also proves that specifically engineered non-metallic products may be successfully operated at the high temperature and high pressure (HPHT) levels that are characteristic of our reservoirs. As a result of this qualification program, ADNOC will see an increase in the longevity of pipeline assets and will enjoy significantly higher reliability and availability, with lower maintenance cost over time. It has been demonstrated that RTP can provide life-cycle savings exceeding 60% when compared to carbon steel pipes [1]. As the polymer feedstock that is used to manufacture these products can be produced regionally, including material supplied in the UAE by Borouge, the manufacturing/use/recycling will close a vital and sustainable full cycle, promoting In-Country Value (ICV) and generating additional economic opportunities in the emerging non-metallic industrial ecosystem for the nation. The multi-faceted value proposition is described in more detail in Figure 1 below. Figure 1 Value and sustainability benefits from increased use of non-metallic materials This is a clear example whereby ADNOC and the UAE continue to demonstrate global leadership by creating and investing in sustainable and energy-efficient technology solutions across the entire value chain while diversifying the national economy.

Hydrogen sulfide poses significant challenges to develop oil and gas fields and manage risks in terms of personal and process safety. There is a great need to accurately interpret a measured H2S concentration from a gas/oil/water sample for material selection and design during development stage and for sulfide scale/corrosion control after water breakthrough. The objective of this work was to develop an integrated tool comprising ionic chemistry and hydrocarbon thermodynamics in a single and easy to use spreadsheet based tool that is also applicable at HPHT (High Pressure High Temperature) and high saline brine conditions. The tool must account for evaporation of water from brine phase and also have the capability to estimate CO2 and H2S partitioning and speciation, bubble points and density calculations, H2S fugacity and pH of the aqueous phase. A simulation tool for ionic chemistry has been developed to model the H2S distribution with Pitzer ion interaction model to account for the speciation of CO2 and H2S, water activity, and the pH of the aqueous phase. The tool was evaluated by comparing the prediction to experimental data at relevant oilfield condition. The dependence of Pitzer's coefficients for ion activity coefficients on temperature and pressure was examined and incorporated into the model, which provides reliable predictions of solubilities and density that are consistent with over 5000 literature data at all conditions tested. Hydrocarbon thermodynamics based on Peng Robinson equation of state with Peneloux specific volume shift correction has been used to model the partition of CO2, H2S and H2O in the gas/oil/water phase. In this paper we present the validation of the tool's capabilities against experimentally measured values over wide ranges of conditions, including single to multiple aliphatic/aromatic hydrocarbons, up to 6 molal NaCl salinities, and temperature up to 200 °C and pressure up to 10,000 psia with reasonable agreements.

New developments often lack regional identity and distinctiveness of place. Before the industrial revolution, landscapes were the result of social, cultural and environmental constraints. Currently, a strong sense of place is lacking in many American cities. Santa Fe, New Mexico, as an example, faces the challenge of integrating new development with existing historic areas. While the downtown central core of Santa Fe has a distinctive and unique character, the outlying fringes of Santa Fe County are being developed in ways that undermine the sense of place that is valued by its residents and visitors. Current county development patterns do not meld with the intimate, small-scale character of the older neighborhoods in the downtown central core areas of the city. To address this issue, this thesis uses theory related to sense of place to identify distinctive characteristics that can be adapted for projects outside Santa Fe's central core. The study uses a mixed method approach, including a literature review and field study methods to assess Santa Fe's distinctive physical characteristics. The results are a set of contemporary community design guidelines for the Santa Fe, New Mexico region that address sense of place in the following categories: (a) Spatial Planning and Architecture: street design characteristics and their physical relationship to architecture; (b) Environmentally Responsive Architecture: architecture design characteristics that respond to the regional environment and Santa Fe Style; (c) Decorative Architectural Details: architectural detail design characteristics that respond to the regional vernacular and the Santa Fe Style; (d) Integration of Architecture and Landscape: open space design the physical relationship between the local landscape and architecture; and, (e) Landscape and Cultural Character: regional landscape and art design characteristics that respond to Santa Fe's environment and culture. The resulting design principles are expressed as guidelines to support sense of place and their application to new development in Santa Fe County. Master of Landscape Architecture

Five organic precursors, 2,5-dimethyl-2,4-hexadiene, 2,5-norbornadiene, α-terpinine, limonene, and styrene have been studied as precursors for plasma deposition of low-k films. The films have been produced under particle-forming conditions in the plasma. Accordingly, films have a granular structure with grain sizes in the range 40–400 nm, as determined by AFM. Annealing at 400 °C preserves the granular structure of the films while the grain size decreases. Of the five precursors examined, 2,5-dimethyl-2,4-hexadiene and 2,5-norbornadiene produce films with the lowest dielectric constant, with a value of 3.3. While the dielectric constant varies with deposition conditions (pressure, flow rate, concentration of precursor), we find that the grain size of the films correlates most closely with the dielectric constant and conclude that the lowest value of the dielectric constant are obtained under conditions that promote the formation of particles larger than about 200 nm.

The blending of ethanol into fuels is expected to increase significantly in the coming years. In some regions of the United States, ethanol has already replaced MTBE as the oxygenate blended into gasoline. Biofuel blends, such as blends of gasoline with ethanol made from biomass, can play an important role in helping governments and corporations meet sustainability targets. However, the introduction of ethanol fuel blends into the market place requires addressing several issues related to phase equilibria. The highly non-ideal mixing of ethanol with hydrocarbons has a dramatic impact on phase behavior, with consequences for the production, storage, distribution, and use of ethanol-blended fuels. In this paper, we will (a) illustrate the impact of ethanol use on the transportation fuels industry, (b) use thermodynamics as a unifying theme to understand these phenomena, and (c) review available data and the state-of-the-art in modeling these effects. Topics will include (a) volatility characteristics (e.g. Reid vapor pressure, ASTM D-86 Distillation, vapor–liquid ratio, and evaporative emissions), (b) phase separation effects (e.g. water tolerance and enhanced solubility of aromatic fuel components in groundwater), (c) commingling of ethanol and non-ethanol fuels, and (d) materials compatibility (e.g. increased swelling and permeation).

For back end of line (BEOL) interconnects, maintaining device reliability while scaling the dielectric stack is a continual challenge. In this paper, the ability to improve the dielectric barrier properties of silicon carbonitride (SiCN) films is discussed. Designing the precursor structure to provide improved film properties in a plasma-enhanced chemical vapor deposition (PECVD) system is demonstrated. The precursor was optimized for maximizing the density value of the deposited film for a given dielectric constant without compromising the electrical properties. For the deposited SiCN films, the nature of carbon bonding was identified as a key structural element correlating to critical barrier film properties such as leakage and hardness.

Ta 2 O 5 films, deposited on bare and nitrogen passivated Si(100) surfaces, were annealed in the presence of three different oxidizing agents, NO, N 2 O, and O 2 , and then examined using X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (TOFSIMS). These films were thin enough to allow spectroscopic examination of the interface between the silicon and the oxide. During deposition of Ta 2 O 5 on bare Si(100), the substrate is oxidized and the amount of oxide increases during subsequent annealing. No nitrogen accumulates when annealing in NO or N 2 O. Angle-resolved XPS and TOFSIMS depth profiles reveal, after annealing, oxidized silicon at the vacuum–solid interface and throughout the oxidized tantalum layer. For Ta 2 O 5 on nitrided Si(100), annealing at 820°C depletes nitrogen in the silicon nitride and increases silicon oxide, regardless of the oxidant used. Temperature programmed reaction spectra of Ta 2 O 5 deposited on previously oxidized Si(100) show SiO desorption above ∽950°C. The annealing results are accounted for in terms of chemical reactions at the buried interface that form SiO and, for the nitrided samples, NO species that migrate toward the vacuum interface. Oxidizing species from the gas phase also migrate to the buried interface to produce additional silicon oxide.

A piezoelectric quartz crystal microbalance (QCM) has been used to measure the sorption of solvents into elastomers. The equipment can operate from ambient temperature and pressure up to 180°C and 60 bar. The polymers are deposited on the quartz crystal from solution to form films on the order of 0.1 to 1 μm. Because the time to reach equilibrium scales with the square of the film thickness, this technique can generate data much more rapidly than alternative gravimetric techniques, such as electronic or quartz spring microbalances. However, at high mass loading the frequency–mass response of the QCM becomes non-linear. For the systems studied this typically occurred at solvent vapor sorption levels of 20 to 30 wt.%. From the sorption data, we have generated the activity coefficient on a weight fraction basis for solvents in these polymers from about 0.01 to 0.3 weight fraction. To test this method on coatings of polymers with heterogeneous morphology, we measured the sorption of solvents into a series of triblock copolymers comprising styrene endblocks and midblocks of butadiene, isoprene, or hydrogenated butadiene. The microphase domain sizes in these polymers are about an order-of-magnitude smaller than the typical film thickness used in these experiments. The results have been correlated with elastomer structure. Where comparisons are possible, these activity coefficients agree reasonably with those measured by conventional methods at finite concentration using bulk polymer samples, but sometimes appear low relative to activity coefficients at infinite-dilution measured by inverse gas chromatography (IGC). Advantages and limitations of the QCM are summarized.

The effects of vacuum and inert gas annealing of ultrathin (∼20 A) tantalum pentoxide (Ta2O5) films deposited on Si(100), with and without nitrogen passivation, were examined. Without nitrogen passivation, annealing Ta2O5 to 820 °C for 10 min led to oxidized silicon at both the Si-Ta2O5 and Ta2O5-vacuum interfaces and some tantalum silicide formation at the Si-Ta2O5 interface. Nitridation inhibited these processes.

This paper addresses the drift of copper ions (Cu/sup +/) in various low-permittivity (low-/spl kappa/) polymer dielectrics to identify copper barrier requirements for reliable interconnect integration in future ULSI. Stressing at temperatures of 150-275/spl deg/C and electric fields up to 1.5 MV/cm was conducted on copper-insulator-silicon capacitors to investigate the penetration of Cu/sup +/ into the polymers. The drift properties of Cu/sup +/ in six industrially relevant low-/spl kappa/ organic polymer insulators-parylene-F, benzocyclobutene, fluorinated polyimide, an aromatic hydrocarbon, and two varieties of poly(arylene ether)-were evaluated and compared by capacitance-voltage, current-time, current-voltage, and dielectric time-to-failure measurements. Our study shows that Cu/sup +/ drifts readily into fluorinated polyimide and poly(arylene ether), more slowly into parylene-F, and even more slowly into benzocyclobutene. Among these polymers, the copper drift barrier property appears to be improved by increased polymer crosslinking and degraded by polar functional groups in the polymers. A thin nitride cap layer can stop the drift. A physical model has been developed to explain the kinetics of Cu/sup +/ drift.

We investigated Ta2O5 films grown by chemical vapor deposition of Ta(N(CH3)2)5 and O2 both bare and SiOxNy-passivated Si(100) using x-ray photoelectron spectroscopy, time-of-flight secondary-ion-mass spectroscopy (TOF-SIMS), and electrical measurements. The SiOxNy-passivated layer was formed by nitric oxide exposure to the Si substrate. Chemical composition of the Ta2O5 films is strongly dependent on the oxygen flow rate during film deposition; lower carbon levels and higher O/Ta ratios are observed for the films grown at higher O2 flow rates. A corresponding leakage current decrease is observed for the films grown at a high O2 flow rate. Compared to Ta2O5 films deposited on bare Si(100), the films deposited on SiOxNy-passivated layers show better electrical properties; with smaller equivalent thickness (Δteq∼6 A), one order of magnitude lower leakage current was measured. TOF-SIMS data indicate that SiOxNy layers (∼9 A) incorporate some oxygen during Ta2O5 deposition; however, regions where x=2, y=0 were...

Recently there have been a number of reports indicating concern relating to the effect of porosity, pore size distribution, and pore interconnectivity on the integration of highly porous ultra low-k organosilicate glasses (OSGs) as back-end-of-line (BEOL) interconnect dielectrics. In an effort to address these concerns a number of options to control the skeleton and pore structure of OSGs have been proposed, from adding alternative OSG precursors to alternative porogen precursors. In all these options there is a need to balance pore structure modification with critical film properties such as dielectric constant and mechanical strength. In this context, this paper examines porosity and its impact on film properties for highly porous ultra low dielectric constant films. A series of PDEMS® porous OSG films were deposited by plasma enchanced chemical vapor deposition (PECVD) from DEMS® precursor (diethoxymethylsilane) and porogen ATRP (alpha-terpenine). The percent porosity and pore interconnectivity of these films relative to the dielectric constant were measured by ellipsometric porosimetry (EP) and positron annihilation spectroscopy (PALS) respectively. Porosity and pore-size distribution for films deposited using several different species (structure former or porogen precursors) were examined using EP in an effort to understand the impact of the chemical nature of the precursor on pore morphology. Results from these depositions show that it is possible to deposit films with smaller pores using alternative structure formers (ASFs) with bulky organic groups, although there are tradeoffs with respect to other film characteristics. The addition of a separate porogen (ATRP) to the ASF lowered the dielectric constant and the addition of DEMS® precursor to the ASF/ATRP mix gave the films added structural integrity and mechanical strength. Such a fundamental understanding of structure-property relationships will help support successful integration of these porous OSG films.

The electrical and physical quality of gate and passivation dielectrics significantly impacts the device performance of thin film transistors (TFTs). The passivation dielectric also needs to act as a barrier to protect the TFT device. As low temperature TFT processing becomes a requirement for novel applications and plastic substrates, there is a need for materials innovation that enables high quality plasma enhanced chemical vapor deposition (PECVD) gate dielectric deposition. In this context, this paper discusses structure-property relationships and strategies for precursor development in silicon nitride, silicon oxycarbide (SiOC) and silicon oxide films. Experiments with passivation SiOC films demonstrate the benefit of a superior precursor (LkB-500) and standard process optimization to enable lower temperature depositions. For gate SiO2 deposition (that are used with polysilicon TFTs for example), organosilicon precursors containing different types and amounts of Si, C, O and H bonding were experimentally compared to the industry standard TEOS (tetraethoxysilane) at different process conditions and temperatures. Major differences were identified in film quality especially wet etch rate or WER (correlating to film density) and dielectric constant (k) values (correlating to moisture absorption). Gate quality SiO2 films can be deposited by choosing precursors that can minimize residual Si-OH groups and enable higher density stable moisture-free films. For e.g., the optimized precursor AP-LTO® 770 is clearly better than TEOS for low temperature PECVD depositions based on density, WER, k charge density (measured by flatband voltage or Vfb); and leakage and breakdown voltage (Vbd) measurements. The design and development of such novel precursors is a key factor to successfully enable manufacturing of advanced low temperature processed devices.

The composite pipe system known as X200™ is a steel strip laminate technology which uses high-performance adhesives to manufacture a metallic composite pipe. It offers a new method of low-cost pipeline construction suitable for onshore gas and oil pipelines in a variety of configurations. The pipe is based on a thin wall liner that provides the fluid containment, the material of which will vary according to service requirements. The grade of steel, stainless steel, special alloy, or even reinforced thermoplastic can be user-defined to suit a given fluid application; the current design is based on 316L stainless steel. Fusion bonded epoxy (FBE) coated ultra-high strength steel strips are pre-formed and helically wound around the liner to form a laminated high strength reinforcing layer providing the pipe’s hoop strength. These components are bonded together to form a rigid pipe, using an adhesive. The complete structure is then coated with one or more layers of a suitable pipeline external coating material, as required by conditions. The resulting pipe is considerably thinner and lighter than the equivalent rated conventional line pipe products because of the beneficial strength-to-weight ratio of the materials utilized. Unlike conventional line pipe that is manufactured in a plate mill, and then transported from the mill to the construction site; X200 pipe can be produced at the job site using a portable manufacturing line – greatly reducing the logistics burden for projects and reducing the time to first hydrocarbon production. All units in the manufacturing process fit within standard ISO containers, each weighing between 5 and 20 tonnes. This allows for economic transportation and handling.

A new technology for external rehabilitation of pipelines, known as XHab™, has been developed. This method involves wrapping multiple layers of ultra-high strength steel (UHSS) strip in a helical form continuously over an extended length of pipeline using a dedicated forming and wrapping machine. The reinforcement afforded by the strip can be used to bring a defective section of pipe (e.g. externally corroded or dented) back to its original allowable operating conditions, or even to increase the allowable operating pressure if the desired operating conditions exceed the original pipeline design limits. This paper describes the design, manufacture and testing process for a self-propelled wrapping machine for in-field rehabilitation. The wrapping apparatus consists of several major components including an opening sufficiently wide to receive the pipe, a movement assembly, a winding head, a preforming device, an accumulator and an oscillating adhesive applicator. The wrapping apparatus uses the winding head to wrap the reinforcing steel strip around the pipe. The movement assembly uses a pair of tracks in contact with the pipe to drive the wrapping apparatus along which enables helical wrapping of the reinforcing strip material. The oscillating adhesive assembly applies structural adhesive to the pipe immediately before the strip is wound. The winding head, motive assembly and adhesive applicator are electronically synchronized to one another to enable precise control of pitch and adhesive volume. The paper also describes the field application of XHab including mobilization/demobilization of equipment and interaction with other rehabilitation equipment, as well as specific aspects such as initiation and termination of wrapping, protection of rehabilitated area and implementation of cathodic protection.Copyright © 2010 by ASME

The composite pipe system, known as XPipe™, is a steel strip laminate technology which uses high-performance adhesives to manufacture a metallic composite pipe. It offers a new method of low cost pipeline construction suitable for onshore gas and oil pipelines in a variety of configurations. The pipe is based on a thin wall liner that provides the fluid containment, the material of which will vary according to service requirements. Fusion bonded epoxy (FBE) coated martensitic ultra-high strength steel strips are then pre-formed and helically wound around the liner to form a laminated high strength reinforcing layer providing the pipe’s hoop strength. These are bonded using an adhesive. Unlike conventional linepipe that is manufactured in a pipe mill away from the construction site, this lightweight composite pipe can be produced at the construction facility using a portable manufacturing line. All components of the manufacturing process fit within standard ISO containers, each weighing between 5 and 15 tonnes. This allows for easy transportation via truck, and handling or shipping. This paper describes the Factory Acceptance Test (FAT) and subsequent Site Integration Test (SIT) of the containerised pipe manufacturing facility. The FAT was performed in factory conditions in Rome, NY (December 2008) and demonstrated acceptable operation of the complete pipe production line. For the SIT, a site in Houston, TX was chosen which would be broadly representative of in-field conditions. The SIT was performed between April and June 2009 and demonstrated acceptable in-field operation of the pipe production system. The paper also describes the results of full-scale testing performed on pipe produced during the SIT and FAT, including burst, tension and cyclic pressure testing pipe sections.Copyright © 2010 by ASME

A new technology for external rehabilitation of pipelines, known as XHab™, has been developed. This method involves wrapping multiple layers of ultra-high strength steel strip (UHSS) in a helical form continuously over an extended length of pipeline using a dedicated forming and wrapping machine. The reinforcement afforded by the strip can be used to bring a defective section of pipe (e.g. externally corroded or dented) back to its original allowable operating conditions, or even to increase the allowable operating pressure if the desired operating conditions exceed the original pipeline design limits. This paper describes the full scale burst testing and analysis of defective pipes which have been repaired using the XHab process. The full scale test sections are 30″ × 0.5″ API 5L X52 DSAW pipe and include the following specimens: • Bare pipe with no defects; • Bare pipe with single machined defect; • Wrapped pipe with single machined defect and designed reinforcement; • Wrapped pipe with single machined defect and insufficient reinforcement; • Wrapped pipe with interacting defect array and designed reinforcement. The above full scale burst tests are supplemented by FEA models using ABAQUS. The material models for the steel pipe, UHSS strip, defect patch material and strip adhesive are based on measured data from the batch tests and tuned against the control burst test results. The structural behavior in the individual metallic and non-metallic elements can therefore be examined more closely, particularly in the region of the defect and where the wrapped strip crosses seam and girth welds.Copyright © 2010 by ASME

The composite pipe system, known as XPipe™, is a steel strip laminate technology which uses high-performance adhesives to manufacture a metallic composite pipe. It offers a new method of low cost pipeline construction suitable for onshore gas and oil pipelines in a variety of configurations. The pipe is based on a thin wall liner that provides the fluid containment, the material of which will vary according to service requirements. Fusion bonded epoxy (FBE) coated martensitic ultra-high strength steel strips are then pre-formed and helically wound around the liner to form a laminated high strength reinforcing layer providing the pipe’s hoop strength. These are bonded using an adhesive. Unlike conventional linepipe that is manufactured in a pipe mill away from the construction site, this lightweight composite pipe can be produced at the construction facility using a portable manufacturing line. All components of the manufacturing process fit within standard ISO containers, each weighing between 5 and 15 tonnes. This allows for easy transportation via truck, and handling or shipping. Existing regulations and codes make no specific reference to metal composite pipes. They are mainly written for steel pipe lines with some mention of plastic pipe. The paper presents a comprehensive review of the following US onshore design codes (ASME B31.4/B31.8) and relevant regulations (CFR (DOT) 49 P192 / P195) in order to establish the applicability of these codes for use on XPipe. The paper describes how XPipe meets the code and regulation requirements with regard to safety, design, material, construction, inspection, testing, operation and maintenance. The paper will identify any areas where XPipe does not meet code and regulation requirements and describe the testing and /or design changes that have been made in order to meet the code requirements. The paper will focus on the how the XPipe can meet the practical requirements of these codes. The paper will describe how the qualification testing is being performed in accordance with DNV-RP-A203 Qualification Procedures for New Technology. The qualification testing focuses on how the XPipe meets or exceeds pipeline safety margins with regard to typical failure modes such as yield, burst, facture, fatigue, collapse, etc. This is a continuous process and is being updated after each step using the available knowledge on the status of the qualification.Copyright © 2010 by ASME

The composite pipe system, known as XPipe™, uses high-performance adhesives to manufacture a metallic composite pipe. Both technical development and a robust manufacturing quality system are required to ensure the safe use of such novel technology. Several aspects are discussed in this paper. Firstly, the use of ultra-high strength martensitic steels in a buried, cathodically protected environment requires an understanding of their susceptibility to hydrogen embrittlement. A series of slow strain rate and constant load tests was performed under polarised conditions to establish any reduction in ductility over samples tested in air. The results are presented and implications for their use in such a system are discussed. Secondly, although the technology to perform quality welds in thin walled austenitic materials using automated orbital techniques is well established, weld inspection by radiographic techniques is not preferred due to the continuous nature of the process and safety considerations. However, the inspection of such welds by ultrasonic techniques is challenging due to the coarse grained nature of the austenitic welds and the thinness of the liner, well below the 6mm normally considered the minimum for conventional weld inspection. Therefore, Automated Ultrasonic Testing (AUT) requires optimized ultrasonic techniques. AUT capabilities and recommendations towards an optimal inspection concept will be discussed in this paper. Thirdly, the manufacture of the liner, ultra-high strength steel strip and adhesive into the XPipe™ composite pipe requires a robust manufacturing control system, which maintains traceability of the incoming materials and controls and records all the essential parameters during pipe production. This is achieved using a sophisticated SCADA system, using feedback from a variety of sensors.Copyright © 2010 by ASME

Tantalum oxide films were deposited on Si substrates by chemical vapor deposition using the precursor Ta[N(CH3)2]5, and an oxidizing agent—O2, H2O, or NO. Temperatures ranged between 400 and 500 °C and total pressures between 10−3 and 9 Torr. NO did not lead to satisfactory film growth rates. Insignificant (

Fabrication of air gap features have been achieved by three processes utilizing the diffusion of materials through a porous OSG layer. The first process involves the decomposition of a PECVD deposited organic material, either thermally or via UV anneal, to create a void with the decomposition by-products diffusing through the porous OSG layer. The second process uses the etch selectivity of XeF2 or BrF3 towards silicon versus OSG to diffuse through the porous OSG layer to etch the underlying silicon. Finally the water solubility of films such as GeO2 or B2O3, which can be easily deposited by PECVD, can be utilized for void formation via dissolution of the sacrificial inorganic layer through the porous OSG.

We report on our work to develop a process for depositing nanoporous organosilicate (OSG) films via plasma enhanced chemical vapor deposition (PECVD). This approach entails codepositing an OSG material with a plasma polymerizable hydrocarbon, followed by thermal annealing of the material to remove the porogen, leaving an OSG matrix with nano-sized voids. The dielectric constant of the final film is controlled by varying the ratio of porogen precursor to OSG precursor in the delivery gas. Because of the need to maintain the mechanical strength of the final material, diethoxymethylsilane (DEMS) is utilized as the OSG precursor. Utilizing this route we are able to deposit films with a dielectric constant of 2.55 to 2.20 and hardness of 0.7 to 0.3 GPa, respectively.

In this paper we examine the relationship between precursor structure and material properties for films produced from several leading organosilicon precursors on a common processing platform. Results from our study indicate that for the precursors tested the nature of the precursor has little effect upon film composition but significant impact on film structure and properties.

Organofluorosilicate glass (OFSG) films with the composition Si:O:C:H:F were deposited via plasma-enhanced CVD from mixtures of trimethylsilane (3MS), silicon tetrafluoride (SiF4), and oxygen (O2). OFSG films have significantly enhanced mechanical strength, thermo-oxidative stability, and adhesion compared with OSG films deposited from 3MS and O2 alone. We propose that the increased density of OFSG, which helps improve mechanical strength, is balanced by the presence on non-polarizable Si-F functionalities, which serve to lower the dielectric constant.

The effects of vacuum and inert gas annealing of ultra-thin (20Å) CVD Ta2O5 films deposited on Si substrates, with and without oxynitride interface layer, on the Ta2O5/Si interface stability were examined extensively by means of in-situ X-ray Photoelectron Spectroscopy (XPS), ex-situ Time-of-Flight Secondary Ion mass Spectrometry (ToF-SIMS), and Temperature Programmed Reaction (TPR). When annealed to 680 °C for up to 50 min, changes in ∼ 20Å Ta2O5 films formed on Si(100) are negligible, but annealing to 820 °C for 10 min in vacuum, Ar or N2 produces major chemical restructuring. SiO is formed at the Ta2O5 - Si(100) interfaces and becomes incorporated into the tantalum oxide. A reduced form of Ta, attributed to TaSix, forms at the buried interface. Extending the annealing time to 20 min produces no further changes. SiO desorbs during annealing at 1000 °C. Nitriding Si prior to forming the Ta2O5 film deposition inhibits these processes.

The industry is strongly interested in integrating low-κ dielectrics with Damascene copper. Otherwise, with conventional materials, interconnects cannot continue to scale without limiting circuit performance. Integration of copper wiring with silicon dioxide (oxide) requires barrier encapsulation since copper drifts readily in oxide. An important aspect of integrating copper wiring with low-κ dielectrics is the drift behavior of copper ions in these dielectrics, which will directly impact the barrier requirements and hence integration complexity.This work evaluates and compares the copper drift properties in six low-κ organic polymer dielectrics: parylene-F; benzocyclobutene; fluorinated polyimide; an aromatic hydrocarbon; and two varieties of poly(arylene ether). Copper/oxide/polymer/oxide/silicon capacitors are subjected to bias-temperature stress to accelerate penetration of copper from the gate electrode into the polymer. The oxide-sandwiched dielectric stack is used to overcome interface instabilities occurring when a low-κ dielectric is in direct contact with either the gate metal or silicon substrate. The copper drift rates in the various polymers are estimated by electrical techniques, including capacitance-voltage, current-voltage, and current-time measurements. Results correlate well with timeto-breakdown obtained by stressing the capacitor dielectrics. Our study shows that copper ions drift readily into fluorinated polyimide and poly(arylene ether), more slowly into parylene-F, and even more slowly into benzocyclobutene. A qualitative comparison of the chemical structures of the polymers suggests that copper drift in these polymers may possibly be retarded by increased crosslinking and enhanced by polarity in the polymer.

The recent demonstrations of manufacturable multilevel Cu metallization have heightened interest to integrate Cu and low-K dielectrics for future integrated circuits. For reliable integration of both materials, Cu may need to be encapsulated by barrier materials since Cu ions (Cu+) might drift through low-K dielectrics to degrade interconnect and device integrity. This paper addresses the use of electrical testing techniques to evaluate the Cu+ drift behavior of low-K polymer dielectrics. Specifically, bias-temperature stress and capacitance-voltage measurements are employed as their high sensitivities are well-suited for examining charge instabilities in dielectrics. Charge instabilities other than Cu+ drift also exist. For example, when low-K polymers come into direct contact with either a metal or Si, interface-related instabilities attributed to electron/hole injection are observed. To overcome these issues, a planar Cu/oxide/polymer/oxide/Si capacitor test structure is developed for Cu+ drift evaluation. Our study shows that Cu+ ions drift readily into poly(arylene ether) and fluorinated polyimide, but much more slowly into benzocyclobutene. A thin nitride cap layer can prevent the penetration.

Material properties are reported of high quality TiN thin films, deposited by a low temperature (400 – 450 C) and low pressure (10 Torr) metalorganic chemical vapor deposition process using tetrakis(diethylamino)Ti and ammonia. Layer resistivities of less than 200 μΩ cm are achieved in 300 to 500 A thick films. The carbon and oxygen content in the films is found to be low (Integration of the MOCVD-TiN films in a Ti/TiN/Al-alloy metallization scheme is also reported. The diffusion barrier performance of the MOCVD-TiN layers is found to exceed that of PVD-TiN layers.