Este trabalho trata sobre o desenvolvimento de sensores magnéticos tipo fluxgate baseados em tecnologia planar. O material utilizado como núcleo é baseado em trabalhos anteriores que determinaram os melhores parâmetros de eletrodeposição de ligas de NiFe para esta aplicação. Foram criados dispositivos funcionais mostrando a usabilidade do material. Também foram propostos 4 novos leiautes com o propósito de melhorar características como sensibilidade, preço, consumo de potência e resolução se comparados com sensores similares atuais. Inicialmente somente dispositivos em escala de milímetros foram criados utilizando placas de circuito impresso como substrato e um processo litográfico baseado em toner de impressora a laser. Este processo é muito simples e permite uma rápida ida do desenho ao protótipo em escala macro sem necessitar de equipamentos especiais. Note que ao contrário de macrofluxgates convencionais, estes dispositivos pode ser diretamente escalonados. Estes protótipos fornecerão os dados necessários para a construção de micro sensores otimizados. Para calcular a intensidade do campo magnético ao qual o núcleo está submetido foram feitas simulações de elementos finitos. A pequenas distâncias do plano, menores que a separação entre as espiras e onde o núcleo ferromagnético se situa, o campo é muito influenciado pela periodicidade da bobina, dando origem a um campo com oscilações periódicas de grande amplitude. Os efeitos desta alta inomogeneidade não é bem conhecido. Utilizando as curvas de histerese medida para os filmes de NiFe foram obtidas as curvas de resposta simulada para um fluxgate. A sensibilidade e a região linear em função do campo de excitação também foram simuladas. Enquanto que a sensibilidade tem um máximo para campos pouco mais intensos que o de saturação do material, decrescendo posteriormente, a região linear apresenta um pico para campos excitatórios baixos. O primeiro foi confirmado pelos resultados experimentais que também mostraram evidências do segundo. Os quatro leiautes são basicamente dois tipos com uma versão dupla cada um. Isto é, empilhando duas camadas de bobinas idênticas consegue-se multiplicar por raiz de dois o campo de excitação utilizando a mesma potência e dobrar o número de bobinas coletoras. Os leiautes propostos mostraram melhor sensibilidade, até oito vezes maior, se comparados com uma referência tirada da literatura. Também o ruído foi menor nas versões de dupla camada. O melhor apresentou um ruído menor que 1/3 da referência, ambos com potências de 1 Wrms. Mas todos leiautes propostos tiveram menor região linear. Todas estas características também foram estudadas em função da potência aplicada que está diretamente ligada a amplitude do campo de excitação. / This work present the development of fluxgate magnetic field sensors based on planar technology. The material for the core of the device is based on early works that determined the best NiFe electrodeposition parameters for this application. Functional devices were created proving the usability of the alloy. Also 4 new layouts were proposed in order to build more sensitivity, cheaper, less power consumption and better resolution sensors. Firstly, only macro scale devices were created using printed circuit board as substrate and a laser printer toner based lithography. This process is very simple and allows a fast way from sketch to macro scale prototypes with no need of special equipments. Unlike the conventional macrofluxgates, these devices can be directly scalonable. This prototypes characterization data will be used to produce optimized microsensors. Some finite element simulations computed the magnetic field produced by a square planar coil to predict the intensity that the core is immersed on. At small distances from the coil\'s plane, smaller than the separation between wires, where the core stands, the field is very influenced by the periodicity of the coil giving rise to periodic profiles. The effects of this high inhomogeneity is not well known. Using the measured hysteresis curve from the NiFe films, the simulated response of a fluxgate sensor was obtained. The simulated sensitivity and linear range as a function of the excitation field amplitude showed some unexpected results. While the sensitivity has a maximum with excitation fields just above the core saturation values decreasing later on, the linear range shows a high peak in low field region. The first were confirmed by the experimental data that also showed strong evidences of the existence of the second one. The 4 new layouts are basically 2 with a double version each. That is, stacking two identical coil layers in order to multiply by 1.41 the excitation field using the same power, double the number of pick-up coils and minimize the undesired perpendicular magnetic field produce by planar coils. The new layout prototypes had better sensitivity, up to eight times higher, related to the reference one taken from literature. Also the noise measured was smaller in the double layers version. The best one presented more then three times less noise than the reference for a power of Wrms. But all of them presented smaller linear range. All this sensors characteristics where also studied as a function of the applied power, that is directly related to the excitation field.

Este trabalho trata sobre o desenvolvimento de sensores magnéticos tipo fluxgate baseados em tecnologia planar. O material utilizado como núcleo é baseado em trabalhos anteriores que determinaram os melhores parâmetros de eletrodeposição de ligas de NiFe para esta aplicação. Foram criados dispositivos funcionais mostrando a usabilidade do material. Também foram propostos 4 novos leiautes com o propósito de melhorar características como sensibilidade, preço, consumo de potência e resolução se comparados com sensores similares atuais. Inicialmente somente dispositivos em escala de milímetros foram criados utilizando placas de circuito impresso como substrato e um processo litográfico baseado em toner de impressora a laser. Este processo é muito simples e permite uma rápida ida do desenho ao protótipo em escala macro sem necessitar de equipamentos especiais. Note que ao contrário de macrofluxgates convencionais, estes dispositivos pode ser diretamente escalonados. Estes protótipos fornecerão os dados necessários para a construção de micro sensores otimizados. Para calcular a intensidade do campo magnético ao qual o núcleo está submetido foram feitas simulações de elementos finitos. A pequenas distâncias do plano, menores que a separação entre as espiras e onde o núcleo ferromagnético se situa, o campo é muito influenciado pela periodicidade da bobina, dando origem a um campo com oscilações periódicas de grande amplitude. Os efeitos desta alta inomogeneidade não é bem conhecido. Utilizando as curvas de histerese medida para os filmes de NiFe foram obtidas as curvas de resposta simulada para um fluxgate. A sensibilidade e a região linear em função do campo de excitação também foram simuladas. Enquanto que a sensibilidade tem um máximo para campos pouco mais intensos que o de saturação do material, decrescendo posteriormente, a região linear apresenta um pico para campos excitatórios baixos. O primeiro foi confirmado pelos resultados experimentais que também mostraram evidências do segundo. Os quatro leiautes são basicamente dois tipos com uma versão dupla cada um. Isto é, empilhando duas camadas de bobinas idênticas consegue-se multiplicar por raiz de dois o campo de excitação utilizando a mesma potência e dobrar o número de bobinas coletoras. Os leiautes propostos mostraram melhor sensibilidade, até oito vezes maior, se comparados com uma referência tirada da literatura. Também o ruído foi menor nas versões de dupla camada. O melhor apresentou um ruído menor que 1/3 da referência, ambos com potências de 1 Wrms. Mas todos leiautes propostos tiveram menor região linear. Todas estas características também foram estudadas em função da potência aplicada que está diretamente ligada a amplitude do campo de excitação. / This work present the development of fluxgate magnetic field sensors based on planar technology. The material for the core of the device is based on early works that determined the best NiFe electrodeposition parameters for this application. Functional devices were created proving the usability of the alloy. Also 4 new layouts were proposed in order to build more sensitivity, cheaper, less power consumption and better resolution sensors. Firstly, only macro scale devices were created using printed circuit board as substrate and a laser printer toner based lithography. This process is very simple and allows a fast way from sketch to macro scale prototypes with no need of special equipments. Unlike the conventional macrofluxgates, these devices can be directly scalonable. This prototypes characterization data will be used to produce optimized microsensors. Some finite element simulations computed the magnetic field produced by a square planar coil to predict the intensity that the core is immersed on. At small distances from the coil\'s plane, smaller than the separation between wires, where the core stands, the field is very influenced by the periodicity of the coil giving rise to periodic profiles. The effects of this high inhomogeneity is not well known. Using the measured hysteresis curve from the NiFe films, the simulated response of a fluxgate sensor was obtained. The simulated sensitivity and linear range as a function of the excitation field amplitude showed some unexpected results. While the sensitivity has a maximum with excitation fields just above the core saturation values decreasing later on, the linear range shows a high peak in low field region. The first were confirmed by the experimental data that also showed strong evidences of the existence of the second one. The 4 new layouts are basically 2 with a double version each. That is, stacking two identical coil layers in order to multiply by 1.41 the excitation field using the same power, double the number of pick-up coils and minimize the undesired perpendicular magnetic field produce by planar coils. The new layout prototypes had better sensitivity, up to eight times higher, related to the reference one taken from literature. Also the noise measured was smaller in the double layers version. The best one presented more then three times less noise than the reference for a power of Wrms. But all of them presented smaller linear range. All this sensors characteristics where also studied as a function of the applied power, that is directly related to the excitation field.

[NiFe] hydrogenases are found in a variety of microorganisms and catalyze the reversible oxidation of hydrogen gas to protons and electrons. This enzyme has generated intense interest due to its contribution to pathogenicity in certain organisms as well as its application in bioremediation and the production of hydrogen as an alternative fuel source. The biosynthesis of the dinuclear active site requires a number of accessory proteins to chaperone and insert the metal cofactors to the awaiting large subunit of hydrogenase. The proteins responsible for nickel delivery to Escherichia coli hydrogenase 3 are HypA, HypB, and SlyD, however the mechanism by which this is accomplished is unclear. The goal of this work was to analyze the metal-binding abilities and protein interactions of these nickel insertion proteins to enhance our understanding of their roles. Isolated N-terminal peptide of HypB has similar high-affinity metal-binding to the full-length protein. This peptide binds nickel in a square planar site with three cysteinyl and a fourth N-terminal amine ligand. Additionally, studies with SlyD and HypA reveal protein interactions that occur during hydrogenase maturation. Pull-down experiments of a tagged variant of hydrogenase revealed multi-protein complexes with HypA, HypB, and SlyD. A complex between SlyD and hydrogenase forms prior to both nickel and iron insertion, supporting chaperone activity of SlyD during hydrogenase maturation. HypA can interact with hydrogenase in the absence of HypB and SlyD, and a possible role as the bridging protein during the nickel insertion event is proposed. In addition, fluorescent imaging of E. coli cells using a fluorescently labeled streptavidin conjugate revealed localization of both Strep-tagged II hydrogenase and HypA at or near the cell membrane, suggesting that enzyme maturation occurs proximal to metal transporters. This work provided a deeper understanding of the role that each of these proteins play in [NiFe] hydrogenase assembly and is helpful for any future applications of this enzyme.

[NiFe] hydrogenases are found in a variety of microorganisms and catalyze the reversible oxidation of hydrogen gas to protons and electrons. This enzyme has generated intense interest due to its contribution to pathogenicity in certain organisms as well as its application in bioremediation and the production of hydrogen as an alternative fuel source. The biosynthesis of the dinuclear active site requires a number of accessory proteins to chaperone and insert the metal cofactors to the awaiting large subunit of hydrogenase. The proteins responsible for nickel delivery to Escherichia coli hydrogenase 3 are HypA, HypB, and SlyD, however the mechanism by which this is accomplished is unclear. The goal of this work was to analyze the metal-binding abilities and protein interactions of these nickel insertion proteins to enhance our understanding of their roles. Isolated N-terminal peptide of HypB has similar high-affinity metal-binding to the full-length protein. This peptide binds nickel in a square planar site with three cysteinyl and a fourth N-terminal amine ligand. Additionally, studies with SlyD and HypA reveal protein interactions that occur during hydrogenase maturation. Pull-down experiments of a tagged variant of hydrogenase revealed multi-protein complexes with HypA, HypB, and SlyD. A complex between SlyD and hydrogenase forms prior to both nickel and iron insertion, supporting chaperone activity of SlyD during hydrogenase maturation. HypA can interact with hydrogenase in the absence of HypB and SlyD, and a possible role as the bridging protein during the nickel insertion event is proposed. In addition, fluorescent imaging of E. coli cells using a fluorescently labeled streptavidin conjugate revealed localization of both Strep-tagged II hydrogenase and HypA at or near the cell membrane, suggesting that enzyme maturation occurs proximal to metal transporters. This work provided a deeper understanding of the role that each of these proteins play in [NiFe] hydrogenase assembly and is helpful for any future applications of this enzyme.

SlyD is a protein involved in [NiFe]-hydrogenase enzyme maturation and, together with HypB and HypA proteins, contributes to the nickel delivery step. To understand the molecular details of this in vivo function, the nickel-binding activity of SlyD was investigated in vitro. SlyD is a monomeric protein that can chelate up to 7 nickel ions with an affinity in the sub-nanomolar range. By truncation and mutagenesis studies we show that the unique C-terminal metal-binding domain of this protein is required for Ni(II) binding and that the protein coordinates this metal non-cooperatively. This activity of SlyD supports the proposed in vivo role of SlyD in nickel homeostasis. In addition to nickel, SlyD can bind a variety of other types of transition metals. Therefore it was feasible that the protein contributes to homeostasis of metals other than nickel. To test this hypothesis, the metal selectivity of the protein was examined. The preference of SlyD for the metals examined could be ordered as follows, Mn(II), Fe(II) < Co(II) < Ni(II) ~ Zn(II) << Cu(I) indicating that the affinity of SlyD for the different metals follows the Irving-Williams series of metal-complex stabilities. Although the protein is unable to overcome the large thermodynamic preference in vitro for Cu(I) and exclude Zn(II) chelation, in vivo studies suggest a Ni(II)-specific function for the protein. To understand the function of SlyD as a metallochaperone, its interaction with HypB was investigated. This investigation revealed that SlyD plays a role in Ni(II) storage in E. coli and can function as a Ni(II)-donor to HypB. This study also revealed that SlyD can modulate the metal-binding as well as the GTPase activities of HypB. Based on the experimental data, a role for the HypB-SlyD complex in [NiFe]-hydrogenase biosynthesis is presented.

SlyD is a protein involved in [NiFe]-hydrogenase enzyme maturation and, together with HypB and HypA proteins, contributes to the nickel delivery step. To understand the molecular details of this in vivo function, the nickel-binding activity of SlyD was investigated in vitro. SlyD is a monomeric protein that can chelate up to 7 nickel ions with an affinity in the sub-nanomolar range. By truncation and mutagenesis studies we show that the unique C-terminal metal-binding domain of this protein is required for Ni(II) binding and that the protein coordinates this metal non-cooperatively. This activity of SlyD supports the proposed in vivo role of SlyD in nickel homeostasis. In addition to nickel, SlyD can bind a variety of other types of transition metals. Therefore it was feasible that the protein contributes to homeostasis of metals other than nickel. To test this hypothesis, the metal selectivity of the protein was examined. The preference of SlyD for the metals examined could be ordered as follows, Mn(II), Fe(II) < Co(II) < Ni(II) ~ Zn(II) << Cu(I) indicating that the affinity of SlyD for the different metals follows the Irving-Williams series of metal-complex stabilities. Although the protein is unable to overcome the large thermodynamic preference in vitro for Cu(I) and exclude Zn(II) chelation, in vivo studies suggest a Ni(II)-specific function for the protein. To understand the function of SlyD as a metallochaperone, its interaction with HypB was investigated. This investigation revealed that SlyD plays a role in Ni(II) storage in E. coli and can function as a Ni(II)-donor to HypB. This study also revealed that SlyD can modulate the metal-binding as well as the GTPase activities of HypB. Based on the experimental data, a role for the HypB-SlyD complex in [NiFe]-hydrogenase biosynthesis is presented.

abstract: The unicellular cyanobacterium Synechocystis sp. PCC 6803 contains a NiFe-type bidirectional hydrogenase that is capable of using reducing equivalents to reduce protons and generate H¬2. In order to achieve sustained H2 production using this cyanobacterium many challenges need to be overcome. Reported H2 production from Synechocystis is of low rate and often transient. Results described in this dissertation show that the hydrogenase activity in Synechocystis is quite different during periods of darkness and light. In darkness, the hydrogenase enzyme acts in a truly bidirectional way and a particular H2 concentration is reached that depends upon the amount of biomass involved in H2 production. On the other hand, in the presence of light the enzyme shows only transient H2 production followed by a rapid and constitutive H2 oxidation. H2 oxidation and production were measured from a variety of Synechocystis strains in which components of the photosynthetic or respiratory electron transport chain were either deleted or inhibited. It was shown that the light-induced H2 oxidation is dependent on the activity of cytochrome b6f and photosystem I but not on the activity of photosystem II, indicating a channeling of electrons through cytochrome b6f and photosystem I. Because of the sequence similarities between subunits of NADH dehydrogenase I in E. coli and subunits of hydrogenase in Synechocystis, NADH dehydrogenase I was considered as the most likely candidate to mediate the electron transfer from hydrogenase to the membrane electron carrier plastoquinone, and a three-dimensional homology model with the associated subunits shows that structurally it is possible for the subunits of the two complexes to assemble. Finally, with the aim of improving the rate of H2 production in Synechocystis by using a powerful hydrogenase enzyme, a mutant strain of Synechocystis was created in which the native hydrogenase was replaced with the hydrogenase from Lyngbya aestuarii BL J, a strain with higher capacity for H2 production. H2 production was detected in this Synechocystis mutant strain, but only in the presence of external reductants. Overall, this study emphasizes the importance of redox partners in determining the direction of H2 flux in Synechocystis. / Dissertation/Thesis / Doctoral Dissertation Molecular and Cellular Biology 2015

The present rapid increase in the number of space missions demands a decrease in the cost of satellite equipment, but also requires the development of instruments that have low power consumption, low weight, and small size.Anisotropic magnetoresistance (AMR) sensors can answer these needs on account of their small size, weight, and power consumption. AMR sensors also produce lower noise than either giant magnetoresistance (GMR) or tunnel magnetoresistance (TMR) devices and are thus more suitable for space applications.The type of AMR sensor developed in this study was a Planar Hall EffectBridge (PHEB) sensor. The FM layer was also coupled with an AFM layer in order to fix the internal magnetization of the FM layer.One technique that was employed in order to meet the low-noise requirement was to make the FM layer thicker than has previously been attempted.In doing so, the exchange bias field between the AFM layer and the FMlayer is no longer high enough to bias the thicker FM layer, so in order to correct this unwanted effect, the material stack was upgraded to two AFM–FM interfaces. With this configuration, it became possible to increase the exchange field by up to 60%. Stronger exchange bias leads to a thicker FMlayer and so to lower noise in the device performance. Another strategy that was used to lower the resistance of the device was to implement an NiFeX alloy instead of the standard NiFe. NiFeX consists of an alloy of NiFe andCu, Ag, or Au; the last of these is known to have very low resistivity.This solution leads to a significant lowering of the device’s resistance. A recent technological advance used to fabricate devices with lower resistance is to deposit a multilayer of AFM–FM.

A multitude of microorganisms possess the ability to metabolise molecular hydrogen (H2). The major enzyme family involved in hydrogen metabolism are Hydrogenases. These enzymes catalyse the reversible conversion of molecular hydrogen to protons and electrons (H2 ↔ 2H+ + 2e-). These enzymes have the potential to be utilised for biotechnological applications such as hydrogen fuel cells, but they also represent promising drug targets for inhibition of bacterial energy metabolism both within the gastrointestinal tract and after infection. Therefore, further understanding and discoveries made in the hydrogenase field warrants progression into applied medical and biotechnological research areas. Hydrogenases are also interesting due to their phylogeny and physiology in a large number of microbial species. These enzymes are categorised by their active site architecture. One well studied, ancient group is termed the [NiFe]-hydrogenases, which all harbour a complex NiFe(CN-)2CO active site in the 'large' catalytic subunit and usually have three iron-sulfur clusters within a 'small' electron transferring partner subunit. [NiFe]-hydrogenases have undergone massive diversification, with four major phylogenetic subgroups arising. The major part of this Thesis concerns work on a Group 4 [NiFe]-hydrogenase that functions in partnership with a formate dehydrogenase as a formate hydrogenlyase (FHL). This FHL complex generates H2 and CO2 from the disproportionation of formate (CHOO- + H+ ↔ H2 + CO2). In this Thesis, genetic and biochemical characterisation of Pectobacterium atrosepticum SCRI1043, a potato pathogen, led to the identification of a novel FHL complex. The [NiFe]-hydrogenase in this organism is similar to that of Escherichia coli Hydrogenase-4, with an extended membrane domain similar to that of respiratory Complex I. Importantly, the P. atrosepticum formate dehydrogenase is selenium-free, while previously characterised FHL complexes have selenocysteine-containing formate dehydrogenases. Using genetic and biochemical approaches it was shown that the [NiFe]-hydrogenase and a formate dehydrogenase were vital for H2 production by P. atrosepticum. Using plant infection assays it was also shown that the gene encoding the formate dehydrogenase was important for full infective ability of P. atrosepticum in potato plants and tubers. The latter part of this Thesis focuses on developing genetic tools to study this novel FHL from P. atrosepticum as well as Hydrogenase-1 and -2 from E. coli.

O presente trabalho trata da obtenção de ligas de NiFe de NiFeCo sob a forma de filmes finos e também no seu uso na tentativa em se construir um sensor magnético tipo fluxgate planar. A técnica de produção utilizada foi a eletrodeposição com regime galvanostático. A solução eletrolítica utilizada era constituída por sais de níquel e ferro e alguns aditivos. Para depositar os filmes de NiFe, o eletrodo auxiliar era constituído de níquel; enquanto que para depositar os filmes de NiFeCo, o eletrodo auxiliar era constituído de cobalto. Os filmes foram depositados em substratos de cobre utilizando densidades de corrente no intervalo de 4 até 28 mA/cm2, com tempos totais de 40 e 60 minutos. A caracterização morfológica foi realizada utilizando Microscopia Eletrônica de Varredura superficial e de seção lateral e para encontrarmos a composição dos elementos presentes na amostra, realizamos a Espectroscopia de Energia Dispersiva e Difração de Raios-X. Quanto à caracterização magnética foi utilizado o Magnetômetro de Amostra Vibrante e também magnetometria utilizando o Superconducting Quantum Interference Devices (este foi utilizado somente para os filmes de NiFeCo) como o elemento detector do equipamento. Os filmes de NiFe crescem com orientações cristalinas ao longo dos planos (110) e (200); as quantidades de níquel e ferro atingem valores constantes a partir da densidade de corrente de 15 mA/cm2 (embora sempre haja mais níquel que ferro); o ponto de menor coercividade magnética (58,4 A/m) também ocorre a partir dessa densidade de corrente, onde filmes com 1 ?m de espessura são conseguidos para um tempo total de 40 minutos. Nota-se uma assimetria para os campos aplicados perpendicular e paralelamente à superfície do filme. Os filmes de NiFeCo crescem com orientações ao longo dos planos (111) e (200). Embora sempre haja mais níquel (constante em 70%), as concentrações de Fe e Co se igualam apenas para uma densidade de corrente próxima de 15mA/cm2. Abaixo desse valor há mais ferro, e acima mais Co. A partir dessa densidade de corrente, novamente observa-se um mínimo no valor da coercividade magnética do material (81 A/m). A partir dessa densidade de corrente, tal grandeza teve seu valor mantido praticamente constante. Para essa densidade de corrente filmes de 6 ?m de espessura são obtidos para um tempo de 40 minutos. Uma menor assimetria magnética é observada comparada com o caso anterior. Por esses dados, acreditamos que o filmes de NiFeCo seja um melhor candidato para a confecção do sensor planar tipo fluxgate, e testes iniciais de sua fabricação também são apresentados. / This work presents the results about the fabrication and characterization of thin films of NiFe and NiFeCo alloys. The attempts to construct the planar fluxgate are also presented. Galvanostatic electrodeposition using an electrolytic solution containing Ni and Fe was used: NiSO4 (0,7 mol/l); NiCl2 (0,02 mol/l); FeSO4 (0,03 mol/l); H3BO3 (0,4 mol/l) and C7H5O3NS.2H2O (0,016 mol/l). The auxiliary electrode was made on Ni for the NiFe films, while another one made on Co was used for the NiFeCo films. Films were deposited on copper substrates using current densities form 4 up to 28 mA/cm2, and total deposition time of 40 and 60 minutes. Structural characterization was performed using Scanning Electron Microscopy (surface and cross-section); Energy Dispersive Spectroscopy, and Xray Diffraction. Magnetic characterization was performed using two methods: the Vibrating Sample Magnetometry and magnetometry using a SQUID (Superconducting Quantum Interference Devices) sensor. NiFe films grow with crystalline planes oriented along the (110) e (200) directions; the amount of each material reach constant values for current densities above 15 mA/cm2 (even though there is always more Ni). The point of minimum magnetic coercivity (58,4 A/m) also occurs for this current density, where films 1 ?m-thick are obtained for a total deposition time of 40 minutes. An asymmetry is observed for magnetic fields applied parallel and perpendicular to the surface of the films. NiFeCo films grow with crystalline planes oriented along the (111) and (200) directions; the amount of Ni remains constant (about 70%) for the whole current density range. The amount of Fe decreases with increasing current density, while the amout of Co shows the opposite behavior. They have equal values for current densities of about 15mA/cm2, where the minimum coercivity of 81A/m is achieved. For higher current densities the coercivity remains constant. For the current density of 15mA/cm2, 6 ?m-thick films are obtained for a total deposition time of 40 minutes. The magnetic asymmetry is smaller than for the case of the NiFe films. According to the obtained data, we believe that NiFeCo is a better candidate for the fabrication of planar magnetic fluxgate sensors. Initial tests for the fabrication of a prototype are also presented.