La durabilité des piles à combustible à membrane échangeuse de protons, jugée à l’heure actuelle insuffisante, est principalement liée à la dégradation des supports de catalyseur cathodiques carbonés. Afin d’augmenter cette durabilité, un fin revêtement de dioxyde d’étain est effectué sur différents types de carbone (nanotubes, noirs et aérogel de carbone). L’objectif est d’obtenir un matériau alliant la morphologie et la conductivité électrique des carbones avec la stabilité thermodynamique du dioxyde d’étain. Plusieurs types de carbone avec des propriétés intrinsèques différentes ont été choisis afin d’avoir un large un panel de textures et de structures. Dans ces travaux de thèse, des études expérimentales ont été effectuées dans le but d’obtenir des revêtements d’oxyde d’étain fins, homogènes et couvrants. Ces études ont mis en l’avant l’influence primordiale de la texture et de la structure du carbone, mais aussi de la valeur du pH du milieu réactionnel sur la qualité et la quantité de revêtement. Il a aussi été montré que les mécanismes de transformation du précurseur en dioxyde d’étain dépendent de la valeur de ce pH. En améliorant les interactions entre la surface des carbones et des espèces réactives, il a été possible dans certains cas de diminuer grandement la quantité de précurseur tout en améliorant la qualité du revêtement. Les dépôts de nanoparticules de platine effectués sur des aérogels de carbone bruts et revêtus ont mis en avant un comportement différent du platine qui a tendance à s’agglomérer lorsqu’il est en contact avec le dioxyde d’étain. Les performances initiales ainsi que la durabilité des électrocatalyseurs en fonction de deux tests de vieillissement accéléré (classique ou démarrage/arrêt) ont ensuite été discutées, mettant en avant des résultats mitigés. / The proton exchange membrane fuel cell’s lifespan is insufficient because of the degradation of carbon used as cathodic catalyst supports. In order to reduce this degradation, a thin tin dioxide coating is synthesized on the surface of different carbonaceous materials (nanotubes, carbon blacks and aerogel). The aim is to combine the morphology and the electric conductivity of the carbon with the thermodynamic stability of the tin dioxide. Carbonaceous materials with different intrinsic properties are chosen for this study to test a wide range of textures and structures. Experimental studies were carried out in order to synthesize a thin, homogeneous and covering tin dioxide coating. The major influences of the texture and structure of carbonaceous materials but also the influence of the pH value on the quantity and quality of the coating are highlighted. It turns out that the mechanism of formation of tin dioxide depends on this pH value. Thanks to the improvement of the interactions between the carbon surface and the reactive species, it was possible, in some cases, to reduce drastically the quantity of precursor. Platinum nanoparticles deposition performed on various materials (raw or coated carbon aerogel) highlights a different platinum behavior. In fact, on the tin dioxide surface, nanoparticles tend to agglomerate together instead of making a homogeneous dispersion. Then, the initial performances and the durability of electrocatalysts tested with two accelerated stress tests (load protocol or start/stop protocol) are evaluated, spotlighting mitigate results.

Planar two-dimensional (2-D) nanostructured indium oxide (InOx) and one-dimensional (1-D) tin oxide (SnO2) semiconductor metal-oxide layers have been utilised for gas sensing applications. Novel layered Surface Acoustic Wave (SAW) based sensors were developed consisting of InOx/SiOxNy/36°YXLiTaO3, InOx/SiNx/SiO2/36°YXLiTaO3 and InOx/SiNx/36°YXLiTaO3 The 1 µm intermediate layers of silicon oxynitride (SiOxNy), silicon nitride (SiNx) and SiO2/SiNx matrix were deposited on lithium tantalate (36°YXLiTaO3) substrates by r.f. magnetron sputtering, electron-beam evaporation and plasma enhanced chemical vapour deposition (PECVD) techniques, respectively. As a gas sensitive layer, a 100 nm thin layer of InOx was deposited on the intermediate layers by r.f. magnetron sputtering. The targeted gases were ozone (O3) and hydrogen (H2). An intermediate layer has multiple functions: protective role for the interdigital transducers' electrodes as well as an isolating effect from InOx sensing layer, thereby improving the sensor performance. The developed SAW sensors' exhibited high response magnitudes with repeatable, reversible and stable responses towards O3 and H2. They are capable of sensing concentrations as low as 20 parts-per-billion for O3 and 600 parts-per-million for H2. Additionally a conductometric type novel sensing structure of SnO2/36°YX LiTaO3 was also developed by depositing a thin layer of SnO2 nanorods by PECVD. The gas sensing performance exhibited repeatable, reversible, stable responses towards NO2 and CO. The surface morphology, crystalline structure and preferred orientation of the deposited layers were investigated by Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). A polycrystalline, oxygen deficient non-stoichiometric InOx with grain sizes of 20-40 nm was revealed. The 1-D nanostructures were characterised by Transmission Electron Microscopy (TEM) showing nanorods with needle-like shape , diameters of 10-20 nm a t the top and 30-40 nm at the base as well as a preferential growth orientation of [ ] on the LiTaO3 substrate. The developed sensors are promising for O3, H2 and CO sensing.

Ce travail de thèse porte sur la modélisation, la fabrication et la caractérisation de Lasers à Cavité Verticale Emettant par la Surface (VCSEL) de grandes dimensions pour la manipulation de solitons de cavité, pour lesquels ces lasers permettraient une manipulation électrique plus souple de ces ondes stationnaires. Pour cela, il est nécessaire de disposer de structures à large zone d'émission uniforme (~100µm). Or, l'injection par électrode annulaire dans les VCSEL émettant par la surface entraîne une inhomogénéité rédhibitoire. Cette étude vise donc à proposer et évaluer des solutions technologiques innovantes pour atteindre une uniformité optimale dans ces dispositifs. Après une introduction dressant un état de l'art des solutions rapportées dans la littérature, nous présentons les travaux que nous avons menés sur la modélisation électrique des lasers pour évaluer les approches génériques de complexité croissante suivantes : l'ajout d'une couche d'étalement du courant en surface (électrode transparente en ITO) ; l'association de cette dernière à une barrière de potentiel (diode Zener) et la discrétisation de l'injection par création de zones localisées de conduction. L'optimisation des électrodes en ITO déposées sur GaAs, l'évaluation de l'apport d'une diode Zener ainsi que la mesure du contraste d'injection obtenu par gravure localisée en surface du composant sont ensuite détaillées. Suite à cette mise au point technologique, l'insertion des solutions que nous avons finalement retenues (gravures localisées et ITO) pour la réalisation de VCSEL est ensuite décrite. Enfin, les caractérisations électro-optiques des composants réalisés sont présentées; elles ont déjà permis d'obtenir des dispositifs de forme allongée émettant 50mW en continu à l'ambiante. Ces premiers résultats prometteurs ont cependant mis en évidence la nécessité d'améliorer encore les propriétés de l'interface ITO/GaAs. Ces solutions pourront alors être mises à profit pour l'application visée mai s également pour la génération de puissance ou encore la réalisation de VCSEL à cavité externe (VECSEL).

<p>Many materials exhibit interesting and novel properties when prepared as thin films. Thin film metal oxides have had an impact on the technological progress of the microelectronics mainly due to their electrical and optical properties. Since the future goes towards the nanometre scale there is an increasing demand for thin film deposition processes that can produce high quality metal oxide films in this scale with high accuracy.</p><p>This thesis describes atomic layer deposition of Ta₂O₅, HfO₂ and SnO₂ thin films and chemical vapour deposition of SnO₂ thin films. The films have been deposited by employing metal iodides and oxygen as precursors. All these processes have been characterised with regards to important processing parameters. The films themselves have been characterised by standard thin film analysing techniques such as x-ray diffraction, scanning electron microscopy, atomic force microscopy and transmission electron microscopy. The chemical and physical properties have been coupled to critical deposition parameters. Furthermore, additional data in the form of electrical and gas sensing properties important to future applications in the field of microelectronics have been examined.</p><p>The results from the investigated processes have shown the power of the metal iodide based atomic layer deposition (ALD) and chemical vapour deposition (CVD) processes in producing high quality metal oxide thin films. Generally no precursor contaminations have been observed. In contrast to metal chloride based processes the metal iodide processes produces films with a higher degree of crystalline quality when it comes to phase purity, roughness and epitaxy. The use of oxygen as oxidising precursor allowed depositions at higher temperatures than normally employed in water based ALD processes and hence a higher growth rate for epitaxial growth was possible.</p>

Many materials exhibit interesting and novel properties when prepared as thin films. Thin film metal oxides have had an impact on the technological progress of the microelectronics mainly due to their electrical and optical properties. Since the future goes towards the nanometre scale there is an increasing demand for thin film deposition processes that can produce high quality metal oxide films in this scale with high accuracy. This thesis describes atomic layer deposition of Ta2O5, HfO2 and SnO2 thin films and chemical vapour deposition of SnO2 thin films. The films have been deposited by employing metal iodides and oxygen as precursors. All these processes have been characterised with regards to important processing parameters. The films themselves have been characterised by standard thin film analysing techniques such as x-ray diffraction, scanning electron microscopy, atomic force microscopy and transmission electron microscopy. The chemical and physical properties have been coupled to critical deposition parameters. Furthermore, additional data in the form of electrical and gas sensing properties important to future applications in the field of microelectronics have been examined. The results from the investigated processes have shown the power of the metal iodide based atomic layer deposition (ALD) and chemical vapour deposition (CVD) processes in producing high quality metal oxide thin films. Generally no precursor contaminations have been observed. In contrast to metal chloride based processes the metal iodide processes produces films with a higher degree of crystalline quality when it comes to phase purity, roughness and epitaxy. The use of oxygen as oxidising precursor allowed depositions at higher temperatures than normally employed in water based ALD processes and hence a higher growth rate for epitaxial growth was possible.

In order to truly understand the process-property behavior of polymer systems it is essential to identify the three dimensional structure of the materials fabricated. For heterogeneous polymer systems such as nanoparticle filled systems, determination of the three dimensional optical properties are particularly difficult. Such information is essential, however, if the behavior of these systems are to be understood and formalized. The purpose of the present research was to develop methods for measuring the optical characteristics of heterogeneous polymer systems nondestructively, in order to characterize their three dimensional behavior. The thesis contains three parts: Part A: Study of an Oriented Uniformly Distributed System: Stretched Isotactic Polypropylene- nano Carbon Black Films (IPP-CB). Three nondestructive optical methods: optical waveguide coupling, Fourier Transform Infrared (FTIR) spectroscopy and x-ray diffraction, were used to investigate the effect of the carbon black on the phase behavior and orientation of the films. It was found that the carbon black has little effect on the crystal form and crystallinity, but has a significant effect on the three dimensional orientation behavior of the polypropylene in the IPP-CB systems. Part B: Study of a non-Uniformly Distributed System: Compression Molded Poly (Methyl Methacrylate) with Nano Indium Tin Oxide (PMMA-ITO) The PMMA-ITO sample is an un-oriented and non-uniformly mixed system which has a grain structure. A unique Break Point Waveguide Method was developed to deal with this problem. It was found that both the refractive index and the extinction coefficient increased with ITO concentration and the samples were three dimensionally random. Part C: Development of Computational Improvements in System Operations Four methods were developed to improve the accuracy of the waveguide methods. They are the Bootstrap Method, the Two-Line Method, the Big Area Method and the Modified Knee method. In conclusion, the three dimensional optical characteristics of two different kinds of heterogeneous polymer systems, oriented uniformly distributed IPP-CB films and non-uniformly distributed PMMA-ITO composites, are obtained and their structures evaluated. Further, several new methods were developed to improve the accuracy of the current optical waveguide methods.

Nanobelts are a new class of semiconducting metal oxide nanowires with great potential for nanoscale devices. The present research focuses on the manipulation of SnO₂ nanobelts suspended in ethanol using microfluidics and electric fields. Dielectrophoresis (DEP) was demonstrated for the first time on semiconducting metal oxide nanobelts, which also resulted in the fabrication of a multiple nanobelt device. Detailed and direct real-time observations of the wide variety of nanobelt motions induced by DEP forces were conducted using an innovative setup and an inverted optical microscope. High AC electric fields were generated on a gold microelectrode (~ 20 µm gap) array, patterned on glass substrate, and covered by a ~ 10 µm tall PDMS (polydimethylsiloxane) channel, into which the nanobelt suspension was introduced for performing the DEP experiments. Negative DEP (repulsion) of the nanobelts was observed in the low frequency range (< 100 kHz) of the applied voltage, which caused rigid body motion as well as deformation of the nanobelts. In the high frequency range (~ 1 MHz - 10 MHz), positive DEP (attraction) of the nanobelts was observed. Using a parallel plate electrode arrangement, evidence of electrophoresis was also found for DC and low frequency (Hz) voltages. The existence of negative DEP effect is unusual considering the fact that if bulk SnO₂ conductivity and permittivity values are used in combination with ethanol properties to calculate the Clausius Mossotti factor using the simple dipole approximation theory; it predicts positive DEP for most of the frequency range experimentally studied. A fluidic nanobelt alignment technique was studied and used in the fabrication of single nanobelt devices with small electrode gaps. These devices were primarily used for conducting impedance spectroscopy measurements to obtain an estimate of the nanobelt electrical conductivity. Parametric numerical studies were conducted using COMSOL Multiphysics software package to understand the different aspects of the DEP phenomenon in nanobelts. The DEP induced forces and torques were computed using the Maxwell Stress Tensor (MST) approach. The DEP force on the nanobelt was calculated for a range of nanobelt conductivity values. The simulation results indicate that the experimentally observed behavior can be explained if the nanobelt is modeled as having two components: an electrically conductive interior and a nonconductive outer layer surrounding it. This forms the basis for an explanation of the negative DEP observed in SnO₂ nanobelts suspended in ethanol. It is thought that the nonconductive layer is due to depletion of the charge carriers from the nanobelt surface regions. This is consistent with the fact that surface depletion is a commonly observed phenomenon in SnO₂ and other semiconducting metal oxide materials. The major research contribution of this work is that, since nanostructures have large surface areas, surface dominant properties are important. Considering only bulk electrical properties can predict misleading DEP characteristics.

Halbleiter-Gassensoren auf der Basis von Zinnoxid spielen in der Überwachung, Steuerung und Regelung von Prozessen sowie bei der Kontrolle von Umweltparametern eine wachsende Rolle. Dies liegt daran, dass sie kostengünstig und hoch sensitiv für diverse Gase sind. Der mögliche Anwendungsbereich wird jedoch durch ihre geringe Selektivität eingeschränkt. Daher stellt die Steigerung der Sensitivitäten von SnO2-Sensoren eine bleibende Forderung an die Forschung und Entwicklung dar. In der Literatur werden verschiedene Methoden zur Beeinflussung von Sensitivität und Selektivität beschrieben. Am weitesten verbreitet sind insbesondere die Modifizierung der Betriebsweise und die Veränderung der Zusammensetzung der Zinnoxidschichten. Diese beiden Wege wurden auch in dieser Arbeit beschritten. Zum einen wurde der thermozyklische Betrieb, der gegenüber dem isothermen bereits zu einer Verbesserung der Selektivität geführt hat, systematisch untersucht. Dies erlaubt die Leistungsfähigkeit des thermozyklischen Verfahrens zu optimieren und noch ungeklärte Phänomene des Detektionsprozesses besser zu beschreiben. Zum anderen waren Modifizierungen der Zinnoxidschicht durch Zusatz fester Ionenleiter Gegenstand detaillierter Untersuchungen. Zusätze von Materialien dieses Typs führen ebenso wie Änderungen im Betriebsmodus zu Selektivitätssteigerungen, insbesondere gegenüber Gasen mit bestimmten funktionellen Gruppen, z.B. primären Alkoholen. Folgende Erkenntnisse wurden in dieser Arbeit erlangt: ·        Thermozyklischer Betrieb Der thermozyklische Betrieb führt zu charakteristischen Leitwert-Zeit-Profilen (LZP). Die Form der LZP (Profilstruktur) ist vom Betriebsregime wie der Aufheiz- und Abkühlungsgeschwindigkeit (Temperaturrate), dem Volumenstrom des Messgases, der Schichtdicke der sensitiven Schicht, dem Elektrodenmaterial und vor allem aber von der Art und Konzentration der Gaskomponente sowie dem Feuchtegehalt des Messgases abhängig. Der Temperaturrate kommt hierbei eine besondere Bedeutung zu. Sie beeinflusst die gasspezifischen nicht-stationären Nichtgleichgewichte an der Sensoroberfläche und somit die LZP sowie die Sensitivitäten. Die Sensitivität kann aus den Sensorsignalen (LZP) als Summenparameter für Temperaturzyklen bestimmt werden. Sie lässt sich als mittlere relative Leitwertänderung bei Gasexposition definieren. Ebenso repräsentativ für die gassensitiven Eigenschaften sind Vorfaktor und Exponent (Sensitivitätskoeffizienten A´ und b´) der aus der Konzentrationsabhängigkeit der Leitwertssumme bestimmbaren Potenzfunktion. Da sich jedoch bereits kleinste Mengen an Reaktanten auf das in Luft bestimmte Leitwert-Zeit-Profil signifikant auswirken und daher diese Profile streuen, ist die Darstellung der Parameter der Potenzfunktion und die Bestimmung der Sensitivität als relative Leitwertänderung in Bezug auf eine definierte geringe Gaskonzentration generell zu bevorzugen. Es wurde exemplarisch gezeigt, dass die unter thermozyklischen Bedingungen ermittelten Sensitivitäten gegenüber CO, Propylen sowie Propanol größer sind als die unter isothermen Betriebsbedingungen bestimmten. Der Zusammenhang von Sensitivität und Schichtdicke ist für verschiedene Gase unterschiedlich ausgeprägt. Profilform und Schichtdicken sind nur selten korrelierbar. Abhängigkeiten der spezifischen Größen der LZP-Maxima (Temperatur, Leitwert) von der Schichtdicke wurden nur für Propylen gefunden. Durch die gezielte Variation von Parametern lassen sich indirekt Schlüsse über die Wechselwirkungen und Mechanismen in porösen gassensitiven Schichten ziehen. Dominierende Effekte von Ad- und Desorption bzw. der Reaktion sowie der Diffusion von Gaskomponenten können in Bezug zueinander gesetzt werden. ·        Gassensitive Eigenschaften von SnO2/NASICON-artigen Kompositen Komposite aus SnO2 und NASICON, bei denen das Na+ im NASICON gegen Li+ oder K+ ausgetauscht wurde, haben eine ähnliche Wirkung auf Sensitivität und Selektivität wie die mit Na+. Die Ergebnisse erweitern die in der Literatur beschriebenen Kenntnisse zur Wirkung ionisch leitender Kompositzusätze. Die Einflüsse der Zusätze sind sowohl durch die LZP als auch durch die daraus berechneten Sensitivitäten bzw. Sensitivitätskoeffizienten A´ und b´ darstellbar. Starke Sensitivitätssteigerungen gegenüber primären Alkoholen wurden für steigende Anteile der Alkaliionen in den Kompositen festgestellt. Dagegen ist die Sensitivität gegenüber sekundären Alkoholen bei Kompositschichten im Vergleich zu reinen SnO2-Schichten kaum verändert. Die für 1- und 2-Propanol im thermozyklischen Betrieb gefundenen Sensitivitäten sind in der Tendenz mit denen unter isothermen Betriebsbedingungen erlangten vergleichbar. ·        Einfluss der Elektroden Es wurden Hinweise darauf gefunden, dass bereits in der Literatur diskutierte Einflüsse der Elektroden auf die gassensitiven Eigenschaften im isothermen Betrieb von SnO2-Schichten auch im thermozyklischen Betrieb auftreten. Weiterhin beeinflusst die Art des Elektrodenmaterials, z.B. Gold und Platin sowie das Ausgangsmaterials zur Elektrodenherstellung spezifisch die Sensorsignale im thermozyklischen Betriebsverfahren. Die Einflüsse der Elektroden sind nicht nur gasspezifisch, sondern bewirken auch Unterschiede je nach verwendeter gassensitiver Schicht. Dabei können LZP, abhängig vom Gas, maßgeblich von der Elektrode oder den Schichtzusätzen beeinflusst sein. ·        Diffuse Reflexion Infrarot Fourier-Transformations Spektroskopie (DRIFTS) Isotherme Messungen der Diffusen Reflexion Infrarot Fourier-Transformations Spektroskopie (DRIFTS) in Abhängigkeit der Zusammensetzung der Gasphase und des gassensitiven Schichtmaterials sind geeignet, um adsorbierte Oberflächenspezies zu detektieren und Vorstellungen bezüglich der Oberflächenprozesse zu erlangen. DRIFTS-Untersuchungen in Luft mit verschiedenen Konzentrationen weisen auf eine höhere Reaktivität des 1-Propanol mit adsorbierten HO-Gruppen verglichen mit der des 2-Propanol hin. Die Ergebnisse deuten zudem an, dass sich die Oberflächenprozesse an SnO2/NASICON(x=3)-Kompositen von denen der reinen SnO2-Schicht unterscheiden, auch wenn sich diese jeweils unabhängig von der Art des Alkohols zeigen.

This thesis focuses on the use of surface modifiers to tune the properties of both metals and metal oxides. Particular attention is given to examine the modification of transparent conducting oxides (TCOs) including indium tin oxide and zinc oxide both through the use of phosphonic acids as well as organic and metal-organic dopants. In this thesis a variety of known and new phosphonic acids are synthesized. A subset of these molecules are then used to probe the relationship between the ability of a phosphonic acid to tune the work function of ITO and how that interrelates with the coverage and molecular orientation of the modifier on the surface. Experimental techniques including XPS, UPS, and NEXAFS are coupled with theoretical DFT calculations in order to more closely examine this relationship. Literature surrounding the modification of zinc oxide with phosphonic acids is not as prevalent as that found for the modification of ITO. Thus, effort is placed on attempting to determine optimal modification conditions for phosphonic acids on zinc oxide. As zinc oxide is already a low work function metal oxide, modifiers were synthesized in an attempt to further decrease the work function of this substrate in an effort to minimize the barrier to carrier collection/injection. Etching of the substrate by phosphonic acids is also examined. In a related technique, n- and p-dopants are used to modify the surfaces of ITO, zinc oxide, and gold and it was found that the work function can be drastically altered, to approximately 3.3 – 3.6 eV for all three of the substrates examined. Surface reactions are straightforward to conduct typically taking only 60 s to achieve this change in work function.

This dissertation has focused on i) optimizing charge transfer rates at indium-tinoxide (ITO) electrodes, and ii) characterization of the supramolecular structure and properties of ultra thin surface modifier films on modified electrodes for various device applications. Commercial ITO surfaces were modified using conducting polymer thin film architectures with and without various chemical activation procedures. Ferrocene derivatives were used as redox probes, which showed dramatic changes in electron transfer rate as the SA-PANI/PAA layers were added to the ITO surface. Highest rates of electron transfer were observed for DMFc, whose oxidation potential coincides with the potential region where these SA-PANI/PAA films reach their optimal electroactivity. Apparent heterogeneous electron transfer rate constants, kS, measured voltammetrically, were ca.10 x higher for SA-PANI/PAA films on ITO, versus clean ITO substrates. These films also showed linear potentiometric responses with retention of the ITO transparency with the capability to create smoothest films using an aqueous deposition protocol, which proved important in other applications. ITO electrodes were also modified via chemisorption of carboxy functionalized EDOTCA and electropolymerization of PEDOTCA/PEDOT copolymers, when properly optimized for thickness and structure, enhance voltammetrically determined electron transfer rates (kS) to solution probe molecules, such as dimethylferrocene (DMFc). Values of kS ≥ 0.4 cm•sec⁻¹, were determined, approaching rates seen on clean gold surfaces. ITO activation combined with formation of these co-polymer films has the effect of enhancing the electroactive fraction of electrode surface, versus a non-activated, unmodified ITO electrode, which acts as a “blocked” electrode. The electroactivity and spectroelectrochemistry of these films helped to resolve the electron transfer rate mechanism and enabled the construction of models in combination with AFM, XPS, UPS and RAIRS studies. The surface topography, structure, composition, work function and contact angle, also revealed other desirable properties for molecular electronic devices. The carboxylic functionality of the EDOTCA molecule adds more desirable properties compared to normal PEDOT films, such as favoring the deposition of smooth films, increasing the optical contrast, participating in hydrogen-bonding, chemisorption to oxide surface, self-doping and providing a linker for incorporation of different functional groups, new molecules, or nanoparticles. Periodic sub-micron electrode arrays can be created using micro-contact printing and electropolymerization. The sinusoidal modulation of the refractive index of such confined conducting polymer nanostructures or nanoparticle stripes allows efficient visible light diffraction. The modulation of the diffraction efficiency at PANI and PEDOT gratings in the presence of an analytical stimulus such as pH or potential demonstrate the sensing capability at these surfaces. The template stripped gold surfaces that are being developed in our lab demonstrate several advantages over commercially available evaporated gold films especially for nanoscale surface modification.