This dissertation describes the design and manufacturing techniques of antireflection coatings for the optical components of the MAESTRO spectrograph. This work was motivated by the need for a high-performance, robust and inexpensive anti-reflection (AR) coating for deep-space, faint object astronomical observations. I have created a new line of AR-filters, optimal for several different glass substrates, with a small number of layers. The possible ease of mass-manufacture of the CoyoteRTM coating is also illustrated here. I also describe a possible new technique for overcoating aluminum and silver reflective films on glass substrates, as well as future directions for research.

Chemical mechanical polishing (CMP) of dielectric and metal films has become a key process in manufacturing devices with ultra large scale integration (ULSI). In a CMP process, planarization is achieved by polishing a wafer with uneven topography using colloidal slurry consisting of sub-micron sized abrasive particles, oxidant and various additives. Hydrogen peroxide and hydroxylamine are commonly used oxidants in copper CMP process. To achieve planarization, the low lying areas have to be protected while the higher areas are polished away. This requires low static dissolution rate of copper in low areas. Another major issue in copper CMP is galvanic corrosion during barrier polishing step where both copper and the barrier metal are exposed to the slurry. The main goal of the research reported in this dissertation is to understand the dissolution and corrosion issues during the removal of copper in hydroxylamine based chemistries. Electrochemical and physical methods such as profilometry were used to obtain copper removal rates. Among the variety of organic compound tested, benzotriazole and salicylhydroxamic acid were identified as potential corrosion inhibitors for copper. The passive film formed on the copper surface by the addition of benzotriazole and salicylhydroxamic acid was characterized by X-ray photoelectron spectroscopy and atomic force microscopy. The passivation and repassivation kinetics were investigated in detail and a passivation mechanism for copper in hydroxylamine in the presence of benzotriazole and salicylhydroxamic acid chemistries is proposed. Copper removal experiments were performed on a specially designed electrochemical abrasion cell (EC-AC) in the presence and absence of inhibitors. The effect of anodic potentials on the dissolution of copper in various chemistries was studied to identify suitable conditions for electro-chemical mechanical planarization process. The extent of galvanic corrosion between copper and tantalum was estimated using electrochemical polarization measurements. A novel setup was designed to make direct measurement of the galvanic current between copper and tantalum and was successfully used to measure galvanic current in various chemical systems. CMP and post CMP cleaning operations account for almost twenty five percent of the total water usage at semiconductor fabrication plants. The waste water has to be treated to remove copper and unused oxidants and organic additives before it can be recycled or disposed. Fundamental studies on the treatment of copper CMP waste water using boron doped diamond electrodes was performed. The feasibility of copper deposition and organic oxidation was established and a design for a novel reactor is proposed.

Rutherford backscattering spectrometry (RBS) is a very versatile and popular technique in materials characterization. ⁴He⁺ ion beams in the keV or MeV range have been widely used to obtain quantitative information regarding the composition and depth distribution of elemental constituents and impurities in thin films. However, in many cases, RBS is ineffective for light element analysis due to overlapping signals caused by heavy elements in the film or backing material. This project proposes using the (³He,p) and (α,p) reactions to develop nuclear reaction techniques for light element analysis in cases where regular RBS cannot accurately determine elemental content. The (³He,p) nuclear reaction for boron, nitrogen, carbon and oxygen in thin films was investigated using incident beams between 2 and 4 MeV. Absolute cross sections were measured at reaction angles of 90° and 135°. These reactions were observed to have regions of constant cross section suitable for elemental content determination. The B(³He,p)C and ¹⁴N(³He,p)¹⁶O reactions were applied to thin films containing boron and nitrogen, and were proven to be an accurate means of determining elemental areal density in thin films in cases where regular RBS was ineffective due to signal interference from heavier elements in the film or backing substrate. Advantages and limitations of the application of the (³He,p) reaction to B, N, C and O will be discussed for each of these elements. The ¹⁹F(α,p)²²Ne nuclear reaction was investigated over the energy range 2200-2500 keV. Cross sections for the ¹⁹F(α,p₀) reaction were measured at a reaction angle of 135°. A strong, isolated resonance near 2315 keV was observed which is suitable for fluorine depth profiling. A computer program was also used to generate simulated yield curves. Resonance parameters were empirically fit to the yield curve obtained using a target with known areal density (atoms/cm²). The program, with these parameters, was applied to accurately simulate yield curves obtained from other targets. The advantages, limitations and applications of this reaction will be discussed.

Particle formation during low pressure SF6/argon etching of silicon in a single wafer parallel plate reactor is studied. Particles are extracted from the exhaust and collected on the wafer. Particle composition and morphology depend on plasma power, etch time, gas composition, and pressure. Primary particles are tens of nanometers in diameter and spherical and chain aggregates as large as 5 mum are observed. Critical powers and etch times are required for the formation of these aggregates. The presence of major gas phase species is determined using mass spectroscopy and optical emission spectroscopy. A three stage mechanism for describing the particle formation (nucleation, heterogeneous growth, and coagulation) is presented. Particle precursor and heterogeneous sources are determined from plasma-dependent, homogeneous, gas-phase reactions and etch product distributions predicted from electrical and etch rate measurements. Dissociation of SF6 into lower molecular weight SFx species and unsaturated SiFx species are primarily responsible for nuclei formation and subsequent, rapid heterogeneous growth by attachment of positive ions.

Surface-relief, submicron period transmission gratings are fabricated in fused silica. A rigorous vector diffraction code, based on the coupled-wave analysis technique, is used to design and analyze the surface relief gratings. When light with wavelength greater than the grating period encounters such element, only zeroth order transmitted and reflected beams propagate, all other diffracted orders are evanescent. These surface-relief gratings act as homogeneous thin film layers of equivalent refractive indices. The equivalent refractive indices depend on grating characteristics, angle of incidence, and incident light polarization. These gratings can be used as equivalent anti-reflection coatings and as polarization elements. Since the grating structures are etched into the substrate material, these optical elements are durable and chemically resistant compared to resist gratings. Subwavelength elements may play a critical role in high power laser systems where damage resistant antireflection and birefringent materials may not exist. By gaining an understanding and being able to control the many variables involved in the grating fabrication process, one-dimensional and two-dimensional submicron period surface-relief resist gratings with rectangular profiles and precisely controlled dimensions are generated. Subsequent pattern transfer etch into underlying substrate layer resulted in one and two-dimensional gratings in fused silica. One-dimensional gratings fabricated in fused silica behaves as polarization elements, giving a maximum measured phase retardation of 50 degrees. To create a polarization insensitive antireflection structure, two-dimensional surface relief gratings are fabricated. These elements exhibited reflectivities near zero percent. The AR structures also showed broadband performance. Application of two-dimensional AR structures on a 16-level diffractive phase plate reduces the surface reflectance of the multilevel phase plate to 0.2%, from 3.3% of that of a bare fused silica surface. Subwavelength grating elements were found to damage when exposed to 45 mJ/cm² and 13 mJ/cm² of laser radiation at 1064 nm and 351 nm wavelength, respectively. The subwavelength gratings have laser damage thresholds comparable to that of bare fused silica. Initial effort on replicating the subwavelength grating structures in polymers yielded promising results, demonstrating the potential for mass production. Replicated elements exhibited no stress birefringence.

The work contained within this document discusses the polymerization and subsequent characterization of Polypyrrole based electrodes for lithium batteries. Polypyrrole and Polypyrrole/polyethyloxy copolymers were compared and contrasted in an attempt to show the superior kinetics of the copolymer electrode. It was found that the diffusion of dopant ions across the electrode and electrolyte interface was increased by on order of magnitude in the copolymer sample. It was also found that the reversibility of the Polypyrrole electrode was greater than that of the copolymer electrode. While the diffusion coefficient of the copolymer electrode was altered to be comparable to that of the transition metal oxide cathodes in production today, the capacity of the copolymer material is still too low to be considered as an alternative cathode material in the lithium battery industry.

The synthesis, structure, and properties of a number of new octasubstituted phthalocyanines, were investigated in this work. Substituent functionality and design has a profound influence on the film forming, and hence, chemical/physical properties of these model molecular electronic materials. Highly ordered thin films, of the benzyl terminated Pc, (2,3,9,10,16,17,23,24-octa(2-benzyloxyethoxy) phthalocyaninato) copper, CuPc(OC₂OBz)₈ and its di-hydrogen analogue were prepared and characterized. These materials form ordered Langmuir films composed of close packed columnar assemblies. Full compression of these materials produces thin films of stable bilayers that show remarkable mechanical stability, and can be transferred with high efficiency to substrates using a horizontal transfer protocol. The physical, spectroscopic, spectroelectrochemical, electrochemical, and electronic properties of these materials were characterized. These properties are strongly dependent on film morphology and structure. The conductivity of these materials relative to the Pc column axis, is highly anisotropic, and with electrochemical doping, the conductivity along the column axis is ca. 10⁻⁶ S/cm. 2,3,9,10,16,17,23,24-Octa(2-benzyloxytriethoxy) phthalocyaninato) copper, and di-hydrogen materials were prepared and characterized. These Pc derivatives did not exhibit the extraordinary properties of their shorter chained analogues. Film preparation efforts with these materials produced poorly ordered isotropic films. Chain length and benzyl termination are combined, in CuPc(OC₂OBz)₈, to produce a unique self assembling material with properties comparable to that reported previously for rigid-rod polymeric Pc materials.

Anode passivation can decrease productivity and quality while increasing costs in modern copper electrorefineries. This investigation utilized electrochemical techniques to characterize the passivation behavior of anode samples from ten different operating companies. It is believed that this collection of anodes is the most diverse set ever to be assembled to study the effect of anode composition on passivation. Chronopotentiometry was the main electrochemical technique, employing a current density of 3820 A m⁻². From statistical analysis of the passivation characteristics, increasing selenium, tellurium, silver, lead and nickel were shown to accelerate passivation. Arsenic was the only anode impurity that inhibited passivation. Oxygen was shown to accelerate passivation when increased from 500 to 1500 ppm, but further increases did not adversely affect passivation. Nine electrolyte variables were also examined. Increasing the copper, sulfuric acid or sulfate concentration of the electrolyte accelerated passivation. Arsenic in the electrolyte had no effect on passivation. Chloride and optimal concentrations of thiourea and glue delayed passivation. Linear sweep voltammetry, cyclic voltammetry, and impedance spectroscopy provided complementary information. Analysis of the electrochemical results led to the development of a unified passivation mechanism. Anode passivation results from the formation of inhibiting films. Careful examination of the potential details, especially those found in the oscillations just prior to passivation, demonstrated the importance of slimes, copper sulfate and copper oxide. Slimes confine dissolution to their pores and inhibit diffusion. This can lead to copper sulfate precipitation, which blocks more of the surface area. Copper oxide forms because of the resulting increase in potential at the interface between the copper sulfate and anode. Ultimate passivation occurs when the anode potential is high enough to stabilize the oxide film in the bulk electrolyte. The effect of anode impurities or electrolyte concentrations can be related to the formation of one of these films. Reactions occurring after passivation have also been examined. Post-passivation reactions are believed to include silver dissolution, transformation of lead sulfate to lead oxide, and oxygen evolution. Following the sharp potential increase caused by the passivation, silver that has accumulated on the anode surface will dissolve into the electrolyte at a potential between 1.0 and 1.3 V. After the silver has dissolved, the potential increases again at which point the oxidation of lead sulfate to lead oxide occurs. The formation of lead oxide provides a surface with a lower oxygen evolution overpotential. The presence of kupferglimmer also results in a stable lower oxygen evolution potential occurring at approximately 2.0 V.

Composites are known for their unique blend of modulus, strength, and toughness. This study focuses on two types of composites; organic-inorganic hybrids and the mineralization of highly swollen polymer gels. Both of these composite systems mimic the biological process of composite formation, known as biomineralization. Biomineralization allows for the control of the precipitating phase through an interaction with the organic matrix. This allows higher volume fractions of inorganic material than can be achieved by many traditional processing techniques. Solid freeform fabrication is a processing method that builds materials by the sequential addition of thin layers. As long as the material can easily be converted from a liquid to a solid, it should be amenable for this processing technique. Freeform fabrication has three distinctions from traditional processing techniques that may enable the formation of composite materials with improved mechanical properties. These are the sequential addition of layers, which allows a layer by layer influence of chemistry, the ability to form complex geometries, and finally, extrusion freeform fabrication has been shown to align fibers due to the extrusion of the slurry through a needle. Cracking and shrinkage still play a major role in forming solid parts. The use of an open mesh structure in combination with proper materials selection allowed the formation of highly loaded composite materials without cracking. The modulus values of these materials ranged from 0.1 GPa to 6.0 GPa. The mechanical properties of these materials were modeled.

The advanced casting modeler requires accurate viscosity and diffusivity data of liquid metals and their alloys. The present work discusses the use of equilibrium and non-equilibrium molecular dynamics techniques to obtain such data without having to rely on oversimplified phenomenological expressions or difficult and expensive experiments. Utilizing the embedded atom method (EAM), the viscosities and diffusivities for a series of equilibrium and non-equilibrium molecular dynamics simulations of nickel, aluminum, and nickel-aluminum alloys are presented. A critical comparison between the equilibrium and non-equilibrium methods is presented. Besides the transport properties, structural data for the liquids are also evaluated. EAM does a poor job of describing the transport properties of nickel-aluminum alloys, particularly near the equiatomic concentration. It has been suggested that charge transfer between nickel and aluminum atoms is responsible for the discrepancy between numerical calculations and available experimental data. A modified electronic distribution function has been developed to simulate the charge transfer associated with compound formation. The effects of such a "charge transfer" modification to the embedded atom method are evaluated. The results of these simulations indicate that the embedded atom method combined with molecular dynamics may be used as a method to predict reasonably the transport properties.