Kesterite Cu2ZnSnS4 (CZTS) is interesting as a sustainable photovoltaic technology due to its earth-abundant elements and suitable semiconducting properties. To date, a record efficiency of 12.6% has been achieved but further improvements are required to reach high efficiency for industrial implementation. Among the limiting issues is the understanding of the annealing process, which is crucial in promoting high material quality. In particular, the knowledge of the effects of segregated secondary compounds on solar cell performance is lacking. In contrast to formation of ZnS particles throughout CZTS film, it is notable that SnS forms and usually segregates on the CZTS top and rear surfaces. The influence of SnS on CZTS solar cells was studied by electron beam induced current measurements. It is found that SnS presence on the CZTS surfacecan introduce “dead area”, whereas it seems beneficial for solar cell current when accumulates on the CZTS rear. For SnS passivation and from investigation of the passivation effect from an Al2O3 thin layer at the CZTS rear, improvement in overall device performance could not be demonstrated, due to either poor CZTS bulk or non-optimal device structure. The limitation in CZTS bulk quality was shown from a thickness study where carrier collection saturated already about 700-1000 nm CZTS thickness. Formation of SnS alongside CZTS implies the anneal is limited by a deficient sulfur partial pressure (PS2). By looking into Sn-S phase transformations in SnS2 films after annealing, we find that PS2 drops rapidly over the annealing time, which could be well-correlated to a series of changes in CZTS material quality including secondary phase formations and defect modifications. It is shown that annealing CZTS under sufficiently high PS2 is critical for CZTS solar cells with high open circuit voltage (upto 783mV was reached), possibly due to the defect modification. Besides SnS, it is observed that NaxS compounds are also readily formed on CZTS surfaces, due to Na diffusion from the glass substrate during annealing. NaxS negatively affects the formation of the CdS/CZTS interface during chemical bath deposition. It can be removed by an oxidation process or wet chemical etching.

Ferroelectric materials have been extensively studied theoretically and experimentally for many decades. Their ferroelectric, piezoelectric, pyroelectric, dielectric and electro-optical properties offer great promise in various applications such as non-volatile random access memory devices, non linear optics, motion and thermal sensors, and tunable microwave devices. Advanced applications for high dielectric constant insulators and nonvolatile memories in semiconductor industry have led to a meteoric rise of interest in the ferroelectrics recently. As most studied and technically important ferroelectric materials, lead zirconate titanate (PZT) and barium strontium titanate (BST) are widely investigated to understand their properties for potential device applications. Using radio frequency magnetron sputtering, single crystalline PZT and BST thin films have been achieved on SrTiO3 substrates, and been characterized for their structural and electrical properties. Eyeing their different potential applications, ferroelectric, pyroelectric and dielectric properties of PZT and BST thin films were studied. In addition, the introduction of bridge layers (nucleation or buffer layers) grown by molecular beam epitaxy (MBE) has been employed to facilitate the heterostructure growth of PZT thin films on GaN and BST thin films on sapphire substrates. Highly (111)-oriented perovskite PZT thin films were achieved on silicon-doped GaN (0001)/c-sapphire with a PbTiO3/PbO oxide bridge layer. And (001)-oriented BST thin films were grown on a-plane sapphire with an MgO/ZnO bridge layer. This dissertation also discusses the realization of PZT ferroelectric field effect transistors (FeFET). Two different 1T FeFET structures were successfully fabricated and their electrical properties were examined. Ferroelectric behavior was observed in the plot of source-drain current versus gate voltage where it exhibited a large counterclockwise hysteresis with 50% current modulation.

Owing to the large electric-field-dependent permittivity, ferroelectric thin films have attracted a great deal of attention on applications in miniature tunable microwave components with high performance and cost reduction, such as phase shifters, tunable oscillators, delay lines, and antennas. These tunable devices require large change in the dielectric constant with applied field and a low loss at microwave frequencies. As one of the promising ferroelectric materials, barium strontium titanate thin film, especially Ba0.5Sr0.5TiO3 (BST) films, have raises great research interests due to its high dielectric constant, which is tunable in an external electric field, combined with relative low loss at microwave frequencies. Tunable microwave components, such as phase shifter, based on the BST films have been widely investigated. Since the polarization, the significant characterization of ferroelectrics, is very sensitive to distortion in crystal structure of ferroelectrics, strain can be effectively utilized to tailor the dielectric properties of BST films. Due to the lattice-mismatch from the substrate and various deposition conditions, epitaxial BST thin film usually contains residual strain generated during film growth. Strain control by improved deposition technique and implementing thermal treatment as well as choosing suitable substrate has attracted intensive attentions in ferroelectric film fabrication. Theory predicts that high dielectric properties can be achieved when free strain or slightly tensile strain left in the BST thin film at room temperature. Microwave application, such as phase shifter, also expects the enhanced tunability by an applied electric field. In this dissertation, single crystalline BST thin films deposited by radio frequency magnetron sputtering on SrTiO3 and DyScO3 substrates were studied. The crystal structure characteristics, including lattice parameters and film strain, were determined using X-ray diffraction. A new growth technique, three-step technique, was introduced and implemented into BST thin film deposition. The application of this new technique in deposition dramatically reduced the compressive strain in the films. We use microwave measurements on coplanar waveguides to evidence the improvement on dielectric properties achieved by tailoring the film strain. Additionally, we studied the BST film deposited by pulsed laser deposition (PLD) with introducing a sputtered seed layer of BST thin film. Compared with the BST film directly deposited on the substrate by PLD deposition, the films with a seed layer showed a large enhancement on the dielectric constant and tunability. The discussion on the change in film strain and dielectric performance of the PLD deposited films further proved the influence of film strain on dielectric properties. We discussed the design, fabrication, and measurement of coplanar waveguide transmission lines as phase shifters fabricated BST films. The thin BST films (~700 nm) on DyScO3 substrates deposited by sputtering demonstrated that the three-step deposition technique improved differential phase shift and microwave figure of merit to a great extent. The introduction of the sputtered seed layer into the PLD deposition of a thicker BST film (~2.15 μm) showed a dramatically enhancement on differential phase shift and microwave figure of merit. The enhanced performance on different series of BST films in microwave frequencies is consistent with the improvement on crystal structure, especially with the change in film strain.

The aim to this work was to develop methods for the determination of 2 aminobiphenyl (2-AB), 3 aminobiphenyl (3-AB), and 4-aminobiphenyl (4-AB) in model mixtures. Concretely, the direct determination of the mixture of studied analytes has been tested using spectrophotometry and differential pulse voltammetry (DPV). Furthermore, separation and detection of 2-AB, 3-AB, and 4-AB have been performed using high performance liquid chromatography with electrochemical detection (HPLC-ED) with boron-doped diamond film thin electrode (BDDFE) in ,,wall-jet" configuration and using high performance liquid chromatography with UV detection (HPLC-UVD). It was found out that the spectrophotometric determination of 2-AB, 3-AB, and 4-AB is impossible in their mixture because of nearby values of local absorption maxima wavelengths of all three analytes studied. Upon the determination of 2-AB, 3-AB, and 4-AB in their mixture using DPV in BR buffer pH 2.0, the difference in peak potentials of 2-AB and 3-AB is too low for their determination in mixture. Upon the determination of mixture containing 2-AB and 4-AB in BR buffer pH 12.0, the limits of determination (LDs) were obtained in the concentration order of 10-6 mol.l-1 for 2-AB and 10-7 mol.l-1 for 4-AB. LDs for the mixture containing 3-AB and 4-AB were obtained in the...

L'objectif de cette thèse est d'étudier le dépôt de couches minces par pulvérisation plasma à l'aide de simulations de dynamique moléculaire, en mettant l'accent sur les mécanismes de la formation de la microstructure dans diverses conditions de dépôt pertinentes pour les expériences. Des dépôts de films minces de ZrxCu100-x et AlCoCrCuFeNi sur Si (100) par procédé magnétron de co-pulvérisation ont été étudiés par simulations de dynamique moléculaire utilisant des conditions initiales similaires à celles des expériences. Les résultats montrent que la phase de films minces ZrxCu100-x est déterminée par la composition de l'alliage binaire et par l'énergie cinétique moyenne des atomes incidents. Les alliages AlCoCrCuFeNi simulés possèdent la structure fcc / bcc modulée par la composition, en conformité avec l'expérience. Ils ont une tendance à évoluer vers une solution solide de verres métalliques massifs a été trouvée. Le dépôt par pulvérisation plasma d'atomes de platine sur deux substrats carbonés nanostructurés (carbone poreux et nanotubes de carbone) a également été étudié à température ambiante (300K) et pour deux ensembles de paramètres de potentiels Lennard-Jones et à trois distributions d’énergie cinétique différentes d'atomes Pt incidents sur le substrat. Les résultats des simulations sont en bon accord avec les résultats expérimentaux. Enfin, la simulation numérique des décharges magnétron a été introduite en vue de déterminer les paramètres d'entrée pour les simulations de MD. Les particules chargées sont décrites par le modèle hydrodynamique, en utilisant des expressions classiques des flux. Les caractéristiques du réacteur sont reproduites par les premières simulations. / The objective of this thesis is to study the deposition of thin films by plasma sputtering using moleculardynamics simulations, focusing on the mechanisms of formation of the microstructure in various deposition conditions relevant to experiments. Deposition of thin films AlCoCrCuFeNi and ZrxCu100-x on Si (100) by magnetron sputtering process of co-sputtering have been studied by molecular dynamics simulations using similar experiments to those initial conditions. The results show that the phase ZrxCu100-x thin films is determined by the composition of the binary alloy and the average kinetic energy of the incident atoms. The simulated AlCoCrCuFeNi alloys have fcc / bcc structure modulated by the composition in accordance with experience. They have a tendency to evolve into a solid solution of bulk metallic glasses found. Plasma deposition of platinum atoms spray on two nanostructured carbon substrates (porous carbon and carbon nanotubes) has also been studied at room temperature (300K) and two sets of parameters of Lennard-Jones potential and three distributions of different kinetic energy Pt atoms incident on the substrate. The simulation results are in good agreement with the experimental results. Finally, the numerical simulation of magnetron discharges was introduced to determine the input parameters for the MD simulations. The charged particles are described by the hydrodynamic model, expressions using conventional flow. The characteristics of the reactor are reproduced by the first simulations.

My dissertation research focuses on the investigation of the transport and magnetic properties of transition metal and rare earth doped oxides, particularly SnO2 and HfO2 thin films. Cr- and Fe-doped SnO2 films were deposited on Al2O3 substrates by pulsed-laser deposition. Xray- diffraction patterns (XRD) show that the films have rutile structure and grow epitaxially along the (101) plane. The diffraction peaks of Cr-doped samples exhibit a systematic shift toward higher angles with increasing Cr concentration. This indicates that Cr dissolves in SnO2. On the other hand, there is no obvious shift of the diffraction peaks of the Fe-doped samples. The magnetization curves indicate that the Cr-doped SnO2 films are paramagnetic at 300 and 5 K. The Fe-doped SnO2 samples exhibit ferromagnetic behaviour at 300 and 5 K. Zero-field-cooled and field-cooled curves indicate super paramagnetic behavior above the blocking temperature of 100 K, suggesting that it is possible that there are ferromagnetic particles in the Fe-doped films. It was found that a Sn0.98Cr0.02O2 film became ferromagnetic at room temperature after annealing in H2. We have calculated the activation energy and found it decreasing with the annealing, which is explained by the increased oxygen vacancies/defects due to the H2 treatment of the films. The ferromagnetism may be associated with the presence of oxygen vacancies although AMR was not observed in the samples. Pure HfO2 and Gd-doped HfO2 thin films have been grown on different single crystal substrates by pulsed laser deposition. XRD patterns show that the pure HfO2 thin films are of single monoclinic phase. Gd-doped HfO2 films have the same XRD patterns except that their diffraction peaks have a shift toward lower angles, which indicates that Gd dissolves in HfO2. Transmission electron microscopy images show a columnar growth of the films. Very weak ferromagnetism is observed in pure and Gd-doped HfO2 films on different substrates at 300 and 5 K, which is attributed to either impure target materials or signals from the substrates. The magnetic properties do not change significantly with post deposition annealing of the HfO2 films.

M.Ing. / This work comprises the implementation and comparison of five design techniques for the design of gradient-index thin film optical filters: classical rugate, inverse Fourier transform, a wavelet-based design procedure, as well as the flip-flop and the genetic optimization techniques. Designs for a high-reflectance filter, a beamsplitter, a discrete level filter, a distributed filter, and an anti-reflection coating were used to compare the various filter synthesis techniques. The optical thickness of the various examples was maintained below 30 and the refractive index excursion limits were between 1.5 and 3.2. The overall performance of a specific design was evaluated by a weighted merit function. The classical rugate filter uses a sinusoidal refractive index modulation that produces a single reflection band. More complex filters are realized by linear superposition of these elementary profiles. Sidelobe and ripple suppression are obtained by applying quintic windowing functions to the refractive index profile and adding matching layers at the edges of the filter. This filter design procedure has the best figure of merit of 3.73 for the discrete level filter, and the second best of 3.09 for the high-reflectance filter. The inverse Fourier transform links the refractive index profile and reflection spectrum of an optical filter by an approximate relation. It is self-correcting and iterative in nature. It produces filters with the highest optical density. The procedure excels in the design of the distributed filter with a figure of merit of 4.17. Mortlett's wavelet is used as the basis of the wavelet design technique. A single wavelet yields a single reflection band, similar to the classical rugate filter. Sidelobe suppression is an inherent property of the method, but matching layers are needed for passband ripple suppression. The optical density of the high reflection filter is larger for a filter designed with this method than for the equivalent classical rugate filter. The figure of merit of 1.75 for the high-reflectance filter is the best for any of the designs. Flip-flop refinement is a brute force approach to filter design. The layers of a starting design are flipped between two values of refractive index, the change in figure of merit evaluated and the best case saved. This process is repeated for a fixed number of iterations. It is computationally intensive and lacks ripple suppression characteristics. The flip-flop method does not compare well with any of the other techniques. It yields filters with the worst figures of merit for most of the design examples. However, it was applied successfully to the anti-reflection coating. The peak ripple for the anti-reflection filter in the 400 nm to 1100 nm wavelength band is 9.62 % compared to the inverse Fourier transform's 57.30 %. The genetic algorithm operates on the principle of "survival of the fittest". It is a stochastic procedure and yields quasi-random refractive index profiles. It excels with the antireflection coating. The peak ripple in the passband of the anti-reflection coating is 3.29%. The figure of merit for the anti-reflection coating designed with the genetic algorithm is 2.09.

L'objectif de cette thèse est de contribuer à la compréhension de l'interaction entre des sollicitations de haute fréquence tangentielles et le déclenchement du glissement macroscopique, ainsi que la dynamique frictionnelle subséquente. Le travail est basé sur une approche expérimentale permettant d'étudier, à des fréquences ultrasonores, les propriétés élastiques et dissipatives de contacts sphère-plan en régime linéaire et non-linéaire. La méthode consiste à mesurer les caractéristiques de la résonance d'un piezoélectrique (fréquence de résonance et facteur de qualité) modifiées par l'établissement d'un contact mécanique. Le seuil de glissement est ajusté par le contrôle de la nature moléculaire de l'interface frictionnelle, constituée de films nanométriques greffés ou déposés par spin-coating. Nous commençons par étudier les propriétés physiques et mécaniques en régime linéaire de ces interfaces contrôlées. Ensuite, nous évaluons l'influence de l'amplitude des oscillations sur le l'angle de repos d'une sonde placée sur un plan incliné. Lorsque l'amplitude augmente, le seuil de glissement est abaissé quelle que soit la polarisation des oscillations. L'effet des vibrations est de diminuer la surface effective sur laquelle est appliquée la contrainte seuil statique, ce qui diminue la force seuil. Nous discutons de ces résultats à l'aide interprétation basée sur l'énergie vibratoire, qui jouerait un rôle proche d'une température effective dans un diagramme de « jamming ».Ensuite, nous étudions le comportement de contacts sphère-plan à de très hautes amplitudes oscillatoires. Nous observons un régime micro-glissement partiel au cours duquel le comportement du contact oscille entre micro-glissement partiel et total. Aux plus hautes amplitudes, les oscillations provoquent une fracture interfaciale et le rayon de contact diminue. Enfin, l'application d'oscillations tangentielles augmente la vitesse de glissement d'un patin soumis à une force constante. Dans le cas d'un film interfacial macromoléculaire, nous discutons des diverses interprétations possibles aux échelles microscopiques / The aim of this work is to bring new insights to the understanding of the interaction between high frequency tangential vibrations and the macroscopic triggering of sliding, as well as the subsequent frictional dynamics. This experimental work is based on a method that allows studying, at ultrasonic frequencies, the elastic and dissipative characteristics of sphere-plane contacts, in linear and non-linear regimes. The method relies on the measurement of the resonance frequency and the quality factor of a quartz, which are modified by the mechanical contact with a probe. The sliding threshold is adjusted by the control of the molecular nature of the frictional interface, which can be either grafted or spin-coated onto the quartz. We first characterize the physical and mechanical properties of the various interfaces in the linear regime. Then, we study the effects of the oscillation amplitude on the angle of repose of the probe in contact with the quartz which is grafted with monolayers of high and low adhesion energy. When the oscillation amplitude increases, the angle of repose decreases whatever the polarisation of the vibrations. The vibrations shall decrease the effective surface area on which the static stress applies, which decreases the static force at the threshold. We discuss the results within the framework of the Mindlin model, which suggests that the oscillatory energy could play the role of an effective temperature in a jamming diagram. In the last part of the work, we study the response of the mechanical contact at very high amplitudes. We observe a micro-slip regime beyond the Mindlin limit, where the behaviour of the contact oscillates between partial and full microslip, leading eventually to interfacial fracture. When the probe is sliding on the incline at constant velocity, the high frequency vibrations increase the sliding velocity. In the case of a macromolecular interfacial film, we propose a possible explanation for this effect, based on a mechanism at the local scale

Orientador: Marcos Fernando de Souza Teixeira / Banca: Ana Maria Pires / Banca: Antonio Carlos Dias Angelo / Resumo: A formação de filmes poliméricos contendo azobenzeno tem recebido atenção especial devido à sua aplicação em dispositivos fotônicos. Neste trabalho estudamos a eletropolimerização de Bismarck Brown R (4-3- (2,4-diamin-5-metilfenil)- 4-metilfenildiazenil]diazenil-6-metilbenzeno-1,3-diamindiclorohidrato), filmes ultra-finos sobre substratos de ITO. Foi realizado o estudo do comportamento do filme polimérico variando-se parâmetros durante a etapa de eletropolimerização para a otimização do poliBBR, visando o desenvolvimento de eletrodos modificados para serem utilizados como sensores químicos. O uso da técnica eletroquímica na preparação de filmes poliméricos tem diversas vantagens, tais como a formação do filme diretamente sobre diferentes substratos, controle de espessura do filme, alta reprodutibilidade, geração de polímeros dopados e possibilidade de imobilização de espécies durante a fase de polimerização. Os filmes ultra-finos depositados nos substratos condutores por eletropolimerização foram caracterizados eletroquimicamente (voltametria cíclica e pulso diferencial), espectroscopia de ultravioleta-visível e microscopia de força atômica (AFM). O trabalho se destaca por possuir pouco ou nenhum relato na literatura sobre os dados obtidos dos estudos eletroquímicos e ópticos do comportamento do polímero de Bismarck Brown R. Foram obtidos dados interessantes no comportamento óptico no estudo da imobilização de íons metálicos na estrutura polimérica do BBR, destacando-se as diferentes geometrias e conformações (cis e trans) investigadas no trabalho / Abstract: The formation of azobenzeno containing polymeric films have been special attention due to its application in photonic devices. In this work we studied the electropolymerization of Bismarck Brown R (4-3-(2,4-diamin-5-methylphenyl)-4-methylphenyldiazenyl]diazenyl-6-methilbenzene-1,3-diamindiclorohidrato), ultra thin films on substrates of ITO. Was carried out study the behavior of the polymer film varying the parameters during the step for the electropolymerization polyBBR optimization, in order to develop modified electrodes to be used as chemical sensors. The use of electrochemical technique for preparing polymer films have several advantages, such as film formation directly on different substrates, film thickness control, high reproducibility, generating doped polymers and possible immobilization of species during the polymerization. The ultra-thin films deposited in conductive substrates were characterized electrochemically (cyclic voltammetry and differential pulse), UV-Vis spectroscopy and atomic force microscopy (AFM). The work stands out due to little or no reports in the literature on data obtained from studies of the electrochemical and optical behavior of polymer Bismarck Brown R. We obtained interesting data on optical behavior in the study immobilization of metal ion in the polymeric structure of the BBR, highlighting the different geometries and conformations (cis and trans) investigated in the work / Mestre

Os antigos e já bem desenvolvidos dispositivos para tratamentos e/ou análise de amostras têm sido grandemente estudados para novas adaptações, devido à importância de se construir sistemas miniaturizados. A obtenção destes sistemas miniaturizados baseia-se não apenas na construção ou metodologia, mas pode depender de modificação superficial para melhoria de desempenho ou diferenciação de aplicações. A modificação de superfície com filmes finos obtidos por plasma é bem conhecida na Microeletrônica. Assim, este trabalho teve como objetivo avaliar a possibilidade do uso da modificação superficial pela produção de filmes finos a partir da polimerização por plasma de Tetraetilortossilicato, TEOS - para fabricação de estruturas miniaturizadas, principalmente para retenção e/ou pré-concentração, em pré-tratamento de amostras ou mesmo para proteção de sistemas de detecção. A metodologia utilizada correspondeu a testes destes filmes em canais ou membranas seletivas. Quanto aos canais utilizou-se geometria planar e/ou tridimensional; as membranas foram testadas em geometria planar. Microcanais tridimensionais, usados tanto em fase gasosa como líquida, foram testados para determinação de retenção/pré-concentração de compostos orgânicos voláteis. Para testes de retenção de compostos inorgânicos em fase líquida (água como solvente) utilizaram-se não só microcanais, tridimensionais ou planares, como também membranas. Proteção de sistemas de detecção exigiu o uso de geometria plana. Quanto ao filme a base de TEOS, este foi testado imediatamente após a deposição, após envelhecimento por no mínimo seis meses ou após exposição a condições adversas como a que levam à hidrólise de radicais orgânicos presentes no filme, ou mesmo após hidrofobização da superfície, por exposição à Hexametildissilazana, HMDS. A construção de dispositivos, com canal planar ou tridimensional, permitiu o desenvolvimento de diferentes sistemas de tratamento, e respectivos métodos de análise, para separação, retenção e pré-concentração de amostras. Os resultados obtidos demonstraram que um dispositivo com canal tridimensional, tratado pela deposição a base de TEOS e posterior hidrólise do filme, permite a retenção de íons e formação de clusters de cobre, em fase líquida. Do mesmo modo, permite a separação de compostos orgânicos em pequena concentração e retenção de compostos polares, em fase gasosa. Para dispositivo planar foi observada a separação de íons através de estrutura plana, similar às utilizadas em eletrocromatografia. Os estudos processados permitiram propor pequenos dispositivos, de baixo custo e fabricação simples, que podem ser facilmente implantados na área de análises. Assim, o canal tridimensional testado tem comportamento semelhante ao de uma pré-coluna. Como é de simples construção e sua entrada e saída possui similaridades com uma pré-coluna comercial, a instalação desta pré-coluna em um cromatógrafo miniaturizado requererá poucas etapas. Essa nova pré-coluna também apresentaria grandes vantagens se fosse adicionada imediatamente antes de detectores não específicos, tais como os usados no nariz eletrônico. Pela diminuição de compostos presentes na mistura, as dificuldades de análise dos resultados igualmente decresce, pela maior facilidade de criação de padrões. / The long-established and well-known devices for sample pretreatment and/or analysis have been widely studied to new adaptations due to the miniaturization trend. The production of these miniaturized systems requires not only new approach on manufacturing and methodology but also depends on surface modification for performance improvement or new applications development. Surface modification using plasma-produced thin films is well established in Microelectronics. Therefore, the aim was to evaluate the use of Plasma polymerized Tetraethylorthosilicate surface modification on manufacturing of miniaturized structures. The main use of such a modification is on devices for sample pretreatment - retention, pre-concentration, or even for protecting detection system surface. The methodology carried out tested these thin films in channels and selective membranes. Whereas channels used three-dimensional and planar geometries, membranes were tested only with planar geometries. Three-dimensional microchannels, used in gaseous or liquid phase, were tested for retention/preconcentration of volatile organic compounds (VOCs). Retention of inorganic compounds in aqueous liquid phase was tested using not only three-dimensional and planar microchannels but also membranes. Protection of detection systems required planar geometry. TEOS thin film was tested after: deposition, ageing for several months; exposition to severe environmental conditions that leads to hydrolysis of organic radicals present in the film; surface hydrophobization due to hexamethyldisilazane, HMDS, exposure. Manufacturing of miniaturized three-dimensional and planar devices leads to some solutions on sample pretreatment and respective analysis methodology. These devices can be used for separation, retention and pre-concentration. The results pointed out that a threedimensional microchannel with plasma deposited TEOS film previously hydrolyzed allows ion retention and clusters formation in a copper aqueous solution. Furthermore, in gaseous phase, VOCs in small concentration can be separated whereas polar compounds can be retained. Planar device allows separation of inorganic ions in a structure similar to the ones used in electrochromatography. Small and low-cost devices are thus here provided, which can easily be machined and are very useful in the chemical analysis field. The three-dimensional microchannel presented behavior similar to the one of a chromatographic pre-column. This microchannel can also be easily adapted to a miniaturized chromatograph. Other possible use is in sample pretreatment, coupled ahead of non-specific detectors, such as electronic noise arrays, since it can decrease the numbers of compounds to be detected and, consequently, reduce drawbacks concerning results analysis.