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Papers by ALAIN SYLVESTRE

Research paper thumbnail of Structure and dielectric study of poly(a, a difluoro-p-xylylene) thin films: highlight of the substrate temperature effect

HAL (Le Centre pour la Communication Scientifique Directe), 2012

International audienc

Research paper thumbnail of The Evaluating of the activation parameters in the transition region of parylene C by thermally stimulated techniques

HAL (Le Centre pour la Communication Scientifique Directe), Sep 1, 2010

International audienc

Research paper thumbnail of Effect of O2, Ar/H2 and CF4 plasma treatments on the structural and dielectric propoerties of parylene-C thin films

HAL (Le Centre pour la Communication Scientifique Directe), 2012

ABSTRACT Plasma treatment of parylene-C surfaces not only causes structural modification of the s... more ABSTRACT Plasma treatment of parylene-C surfaces not only causes structural modification of the surface during the plasma exposure, but also leaves active sites on the surfaces, which decreases the dielectric properties. In this work, the effects of oxygen, argon/hydrogen and fluorine plasma treatment on the surface and dielectric properties of parylene-C thin films were investigated using Fourier transform-IR spectroscopy, energy dispersive x-ray analysis and dielectric spectroscopy measurement. The results showed that the plasma treatment successfully introduced fluorine functional groups and decreased the oxygen content on the parylene-C surfaces. It appears that the replacement of oxygen and hydrogen by fluorine atoms led to a decrease in the local orientational polarizability of parylene-C. Consequently, it was found that the atmospheric fluorine plasma-treated parylene-C possessed lower dielectric characteristics, 16% lower than the untreated parylene-C at industrial frequencies (10–104 Hz). The Ar/H2 plasma treatment is also an experimental means to reduce the dielectric properties and to decrease the oxygen content in parylene-C. In contrast, the oxygen plasma increases the dielectric constant and can cause deterioration of the leakage current associated with carbon depletion showing C–O and C=O formation. CF4 and Ar/H2 plasma treatment does not significantly affect the long molecular motion (α-relaxation). Additional extrinsic oxygen content due to O2 plasma treatment in the parylene-C structure reproduces the increase in the time constant of both the short (β-relaxation) and long molecular motion.

Research paper thumbnail of Structure and Dielectric Study of Poly(α,α difluoro-p-xylylene) Thin Films: Highlight of the Substrate Temperature Effect

Chemical Vapor Deposition, May 7, 2012

for providing financial support during the preparation of the PhD. thesis.

Research paper thumbnail of Low-frequency dielectric functions of dense and chevronic thin films of parylene C

Materials Letters, Mar 1, 2013

Dense and chevronic thin films of parylene C were fabricated using a physicochemical vapor deposi... more Dense and chevronic thin films of parylene C were fabricated using a physicochemical vapor deposition technique and their dielectric functions were measured as functions of frequency (from 0.1 Hz to 0.1 MHz) and temperature (from À 140 1C to 260 1C) using an impedance meter. The real part of the dielectric function of the chevronic thin film was considerably higher than that of its dense counterpart. Higher dielectric strength, loss factor and conductivity for the chevronic parylene suggest an amorphous phase which are more present in this semi-crystalline polymer. X-ray diffractions are now envisaged to confirm this assumption.

Research paper thumbnail of Dielectric relaxation study of amorphous TiTaO thin films in a large operating temperature range

Journal of Applied Physics, Nov 1, 2012

Two relaxation processes have been identified in amorphous TiTaO thin films deposited by reactive... more Two relaxation processes have been identified in amorphous TiTaO thin films deposited by reactive magnetron sputtering. The parallel angle resolved x-ray photoelectron spectroscopy and field emission scanning electron microscopy analyses have shown that this material is composed of an agglomerates mixture of TiO2, Ta2O5, and Ti-Ta bonds. The first relaxation process appears at low temperature with activation energy of about 0.26 eV and is related to the first ionisation of oxygen vacancies and/or the reduction of Ti4+ to Ti3+. The second relaxation process occurs at high temperature with activation energy of 0.95 eV. This last peak is associated to the diffusion of the doubly ionized oxygen vacancies VÖ. The dispersion phenomena observed at high temperature can be attributed to the development of complex defect such as (VÖ − 2Ti3+).

Research paper thumbnail of Anomalous C-V response correlated to relaxation processes in TiO<sub>2</sub> thin film based-metal-insulator-metal capacitor: Effect of titanium and oxygen defects

Journal of Applied Physics, Apr 15, 2015

Capacitance-voltage (C-V) and capacitance-frequency (C-f) measurements are performed on atomic la... more Capacitance-voltage (C-V) and capacitance-frequency (C-f) measurements are performed on atomic layer deposited TiO 2 thin films with top and bottom Au and Pt electrodes, respectively, over a large temperature and frequency range. A sharp capacitance peak/discontinuity (C-V anomalous) is observed in the C-V characteristics at various temperatures and voltages. It is demonstrated that this phenomenon is directly associated with oxygen vacancies. The C-V peak irreversibility and dissymmetry at the reversal dc voltage are attributed to difference between the Schottky contacts at the metal/TiO 2 interfaces. Dielectric analyses reveal two relaxation processes with degeneration of the activation energy. The low trap level of 0.60-0.65 eV is associated with the first ionized oxygen vacancy at low temperature, while the deep trap level of 1.05 eV is associated to the second ionized oxygen vacancy at high temperature. The DC conductivity of the films exhibits a transition temperature at 200 C, suggesting a transition from a conduction regime governed by ionized oxygen vacancies to one governed by interstitial Ti 3þ ions. Both the C-V anomalous and relaxation processes in TiO 2 arise from oxygen vacancies, while the conduction mechanism at high temperature is governed by interstitial titanium ions. V

Research paper thumbnail of Space charge distribution measurement methods and particle loaded insulating materials

Journal of Physics D, Feb 17, 2006

In this paper the authors discuss the effects of particles (fillers) mixed in a composite polymer... more In this paper the authors discuss the effects of particles (fillers) mixed in a composite polymer on the space charge measurement techniques. The origin of particle-induced spurious signals is determined and silica filled epoxy resin is analysed by using the laser-induced-pressure-pulse (LIPP), the pulsed-electroacoustic (PEA) and the laser-induced-thermal-pulse (LITP) methods. A spurious signal identified as the consequence of a piezoelectric effect of some silica particles is visible for all the methods. Moreover, space charges are clearly detected at the epoxy/silica interface after a 10-kV/mm poling at room temperature for 2 hours.

Research paper thumbnail of Impedance spectroscopic and dielectric analysis of Ba0.7Sr0.3TiO3 thin films

Journal of Alloys and Compounds, Jul 1, 2012

Polycrystalline Ba 0.7 Sr 0.3 TiO 3 thin film with Pt/BST/Pt/TiO 2 /SiO 2 structure was prepared ... more Polycrystalline Ba 0.7 Sr 0.3 TiO 3 thin film with Pt/BST/Pt/TiO 2 /SiO 2 structure was prepared by ion beam sputtering. The film was post annealed at 700 • C. The dielectric and electric modulus properties were studied by impedance spectroscopy over a wide frequency range [0.1-10 5 Hz] at different temperatures [175-350 • C]. The Nyquist plots (Z vs. Z) show the contribution of both grain and grain boundaries at higher temperature on the electric response of BST thin films. Moreover, the resistance of grains decreases with the rise in temperature and the material exhibits a negative temperature coefficient of resistance. The electric modulus plot indicates the non-Debye type of dielectric relaxation. The values of the activation energy computed from both plots of Z and M are 0.86 eV and 0.81 eV respectively, which reveals that the species responsible for conduction are the same. The scaling behavior of M /M max shows the temperature independent nature of relaxation time. The plot of normalized complex dielectric modulus and impedance as a function of frequency exhibits both short and long-range conduction in the film.

Research paper thumbnail of Ac-conductivity and dielectric relaxations above glass transition temperature for parylene-C thin films

HAL (Le Centre pour la Communication Scientifique Directe), 2012

ABSTRACT 45% semi-crystalline parylene-C (–H2C–C6H3Cl–CH2–)n thin films (5.8 μm) polymers have be... more ABSTRACT 45% semi-crystalline parylene-C (–H2C–C6H3Cl–CH2–)n thin films (5.8 μm) polymers have been investigated by broadband dielectric spectroscopy for temperatures above the glass transition (T g =90°C). Good insulating properties of parylene-C were obtained until operating temperatures as high as 200°C. Thus, low-frequency conductivities from 10−15 to 10−12 S/cm were obtained for temperatures varying from 90 to 185°C, respectively. This conductivity is at the origin of a significant increase in the dielectric constant at low frequency and at high temperature. As a consequence, Maxwell–Wagner–Sillars (MWS) polarization at the amorphous/crystalline interfaces is put in evidence with activation energy of 1.5 eV. Coupled TGA (Thermogravimetric analysis) and DTA (differential thermal analysis) revealed that the material is stable up to 400°C. This is particularly interesting to integrate this material for new applications as organic field effect transistors (OFETs). Electric conductivity measured at temperatures up to 200°C obeys to the well-known Jonscher law. The plateau observed in the low frequency part of this conductivity is temperature-dependent and follows Arrhenius behavior with activation energy of 0.97 eV (deep traps).

Research paper thumbnail of パラメータプロセスの制御による化学蒸着により堆積したパリレンDの化学的,物理的,および電気的性質の改善【Powered by NICT】

Materials Chemistry and Physics, 2017

Research paper thumbnail of Electroluminescence study of "on" and "off state breakdown in InP based HEMTs

Research paper thumbnail of Stuctural and dielectric study of parylene C thin films

HAL (Le Centre pour la Communication Scientifique Directe), Sep 1, 2009

International audienc

Research paper thumbnail of Dielectric relaxation study of amorphous of TiTaO thin films in a large operating temperature range

Research paper thumbnail of Structural and dielectric properties study of chlorinated and not chlorinated poly(p-xylylene)

HAL (Le Centre pour la Communication Scientifique Directe), Apr 1, 2010

International audienc

Research paper thumbnail of Propriétés diélectrique de couche mince de TiTaO

HAL (Le Centre pour la Communication Scientifique Directe), Mar 18, 2012

National audienc

Research paper thumbnail of Performance improvements of the hydrophobic and the dielectric properties of parylene C

Journal of Applied Physics, Oct 18, 2013

The increase in the hydrophobicity at the same time as the reduction in the dielectric properties... more The increase in the hydrophobicity at the same time as the reduction in the dielectric properties of an insulating material are the main factors necessary to improve the signal response of the electrowetting-on-dielectric and the organic field effect transistor electronic devices. Oxygen (O 2) and fluorine (CF 4) plasma treatments on 3.7 lm thicknesses-parylene C were carried out to understand the surface hydrophobicity character and their effect on the dielectric properties of the material. Fast hydrophobic recovery was observable during the first day after the O 2 treatment due to the reorientation of the polar polymer end chains to the bulk of parylene C. CF 4 plasma treatments reveal a noticeably increase of the hydrophobicity as the treatment time increases. Energy dispersive X-ray and Fourier transform infrared analyses have confirmed an increase in the number of fluorine containing CF x bonds where 1 x 3 after fluorine plasma treatments and after aging. The PPX C film treated with CF 4 plasma at 500 W for 30 min indicated the best hydrophobic character and the best dielectric properties due to the highest loading fluorine content in our experimental conditions. V

Research paper thumbnail of Improvement of chemical, physical, and electrical properties of parylene-D deposited by chemical vapor deposition by controlling the parameters process

Materials Chemistry and Physics, 2017

Surface and bulk properties of paryl ene D are sensitive to the T pyr and T sub. The sublimation ... more Surface and bulk properties of paryl ene D are sensitive to the T pyr and T sub. The sublimation temperature strongly affects the layer growth rate of parylene D. Nearly amorphous parylene-D is obtained when sublimation temperatures are height. Pyrolysis temperatures (T pyr) impact more the surface quality compared to the T sub. Dielectric properties are very sensitive to the parameter processes change.

Research paper thumbnail of Dielectric properties of parylene AF4 as low-k material for microelectronic applications

Thin Solid Films, 2012

Using dielectric spectroscopy analysis, three relaxation mechanisms have been identified in 60% s... more Using dielectric spectroscopy analysis, three relaxation mechanisms have been identified in 60% semi-crystalline parylene AF4 ([–F2C–C6H4–CF2–]n) fluoropolymers. At high temperature, fluorine species located at the electrode/polymer interface involve a space-charge polarization. β-Process assigned to local molecular motions of the C–F dipoles and the γ-relaxation due to local fluctuations of the F2C–C6H4 groups are also evidenced at intermediate and cryogenic temperatures

Research paper thumbnail of Microstructures électrostatiques de récupération d'énergie vibratoire pour les microsystèmes

Innovations technologiques

HAL - hal.archives-ouvertes.fr, CCSd - Centre pour la Communication Scientifique Direct. Accueil;... more HAL - hal.archives-ouvertes.fr, CCSd - Centre pour la Communication Scientifique Direct. Accueil; Dépôt: S'authentifier; S'inscrire. Consultation: Par domaine; Les 30 derniers dépôts; Par année de publication, rédaction, dépôt; Par type de publication; ...

Research paper thumbnail of Structure and dielectric study of poly(a, a difluoro-p-xylylene) thin films: highlight of the substrate temperature effect

HAL (Le Centre pour la Communication Scientifique Directe), 2012

International audienc

Research paper thumbnail of The Evaluating of the activation parameters in the transition region of parylene C by thermally stimulated techniques

HAL (Le Centre pour la Communication Scientifique Directe), Sep 1, 2010

International audienc

Research paper thumbnail of Effect of O2, Ar/H2 and CF4 plasma treatments on the structural and dielectric propoerties of parylene-C thin films

HAL (Le Centre pour la Communication Scientifique Directe), 2012

ABSTRACT Plasma treatment of parylene-C surfaces not only causes structural modification of the s... more ABSTRACT Plasma treatment of parylene-C surfaces not only causes structural modification of the surface during the plasma exposure, but also leaves active sites on the surfaces, which decreases the dielectric properties. In this work, the effects of oxygen, argon/hydrogen and fluorine plasma treatment on the surface and dielectric properties of parylene-C thin films were investigated using Fourier transform-IR spectroscopy, energy dispersive x-ray analysis and dielectric spectroscopy measurement. The results showed that the plasma treatment successfully introduced fluorine functional groups and decreased the oxygen content on the parylene-C surfaces. It appears that the replacement of oxygen and hydrogen by fluorine atoms led to a decrease in the local orientational polarizability of parylene-C. Consequently, it was found that the atmospheric fluorine plasma-treated parylene-C possessed lower dielectric characteristics, 16% lower than the untreated parylene-C at industrial frequencies (10–104 Hz). The Ar/H2 plasma treatment is also an experimental means to reduce the dielectric properties and to decrease the oxygen content in parylene-C. In contrast, the oxygen plasma increases the dielectric constant and can cause deterioration of the leakage current associated with carbon depletion showing C–O and C=O formation. CF4 and Ar/H2 plasma treatment does not significantly affect the long molecular motion (α-relaxation). Additional extrinsic oxygen content due to O2 plasma treatment in the parylene-C structure reproduces the increase in the time constant of both the short (β-relaxation) and long molecular motion.

Research paper thumbnail of Structure and Dielectric Study of Poly(α,α difluoro-p-xylylene) Thin Films: Highlight of the Substrate Temperature Effect

Chemical Vapor Deposition, May 7, 2012

for providing financial support during the preparation of the PhD. thesis.

Research paper thumbnail of Low-frequency dielectric functions of dense and chevronic thin films of parylene C

Materials Letters, Mar 1, 2013

Dense and chevronic thin films of parylene C were fabricated using a physicochemical vapor deposi... more Dense and chevronic thin films of parylene C were fabricated using a physicochemical vapor deposition technique and their dielectric functions were measured as functions of frequency (from 0.1 Hz to 0.1 MHz) and temperature (from À 140 1C to 260 1C) using an impedance meter. The real part of the dielectric function of the chevronic thin film was considerably higher than that of its dense counterpart. Higher dielectric strength, loss factor and conductivity for the chevronic parylene suggest an amorphous phase which are more present in this semi-crystalline polymer. X-ray diffractions are now envisaged to confirm this assumption.

Research paper thumbnail of Dielectric relaxation study of amorphous TiTaO thin films in a large operating temperature range

Journal of Applied Physics, Nov 1, 2012

Two relaxation processes have been identified in amorphous TiTaO thin films deposited by reactive... more Two relaxation processes have been identified in amorphous TiTaO thin films deposited by reactive magnetron sputtering. The parallel angle resolved x-ray photoelectron spectroscopy and field emission scanning electron microscopy analyses have shown that this material is composed of an agglomerates mixture of TiO2, Ta2O5, and Ti-Ta bonds. The first relaxation process appears at low temperature with activation energy of about 0.26 eV and is related to the first ionisation of oxygen vacancies and/or the reduction of Ti4+ to Ti3+. The second relaxation process occurs at high temperature with activation energy of 0.95 eV. This last peak is associated to the diffusion of the doubly ionized oxygen vacancies VÖ. The dispersion phenomena observed at high temperature can be attributed to the development of complex defect such as (VÖ − 2Ti3+).

Research paper thumbnail of Anomalous C-V response correlated to relaxation processes in TiO<sub>2</sub> thin film based-metal-insulator-metal capacitor: Effect of titanium and oxygen defects

Journal of Applied Physics, Apr 15, 2015

Capacitance-voltage (C-V) and capacitance-frequency (C-f) measurements are performed on atomic la... more Capacitance-voltage (C-V) and capacitance-frequency (C-f) measurements are performed on atomic layer deposited TiO 2 thin films with top and bottom Au and Pt electrodes, respectively, over a large temperature and frequency range. A sharp capacitance peak/discontinuity (C-V anomalous) is observed in the C-V characteristics at various temperatures and voltages. It is demonstrated that this phenomenon is directly associated with oxygen vacancies. The C-V peak irreversibility and dissymmetry at the reversal dc voltage are attributed to difference between the Schottky contacts at the metal/TiO 2 interfaces. Dielectric analyses reveal two relaxation processes with degeneration of the activation energy. The low trap level of 0.60-0.65 eV is associated with the first ionized oxygen vacancy at low temperature, while the deep trap level of 1.05 eV is associated to the second ionized oxygen vacancy at high temperature. The DC conductivity of the films exhibits a transition temperature at 200 C, suggesting a transition from a conduction regime governed by ionized oxygen vacancies to one governed by interstitial Ti 3þ ions. Both the C-V anomalous and relaxation processes in TiO 2 arise from oxygen vacancies, while the conduction mechanism at high temperature is governed by interstitial titanium ions. V

Research paper thumbnail of Space charge distribution measurement methods and particle loaded insulating materials

Journal of Physics D, Feb 17, 2006

In this paper the authors discuss the effects of particles (fillers) mixed in a composite polymer... more In this paper the authors discuss the effects of particles (fillers) mixed in a composite polymer on the space charge measurement techniques. The origin of particle-induced spurious signals is determined and silica filled epoxy resin is analysed by using the laser-induced-pressure-pulse (LIPP), the pulsed-electroacoustic (PEA) and the laser-induced-thermal-pulse (LITP) methods. A spurious signal identified as the consequence of a piezoelectric effect of some silica particles is visible for all the methods. Moreover, space charges are clearly detected at the epoxy/silica interface after a 10-kV/mm poling at room temperature for 2 hours.

Research paper thumbnail of Impedance spectroscopic and dielectric analysis of Ba0.7Sr0.3TiO3 thin films

Journal of Alloys and Compounds, Jul 1, 2012

Polycrystalline Ba 0.7 Sr 0.3 TiO 3 thin film with Pt/BST/Pt/TiO 2 /SiO 2 structure was prepared ... more Polycrystalline Ba 0.7 Sr 0.3 TiO 3 thin film with Pt/BST/Pt/TiO 2 /SiO 2 structure was prepared by ion beam sputtering. The film was post annealed at 700 • C. The dielectric and electric modulus properties were studied by impedance spectroscopy over a wide frequency range [0.1-10 5 Hz] at different temperatures [175-350 • C]. The Nyquist plots (Z vs. Z) show the contribution of both grain and grain boundaries at higher temperature on the electric response of BST thin films. Moreover, the resistance of grains decreases with the rise in temperature and the material exhibits a negative temperature coefficient of resistance. The electric modulus plot indicates the non-Debye type of dielectric relaxation. The values of the activation energy computed from both plots of Z and M are 0.86 eV and 0.81 eV respectively, which reveals that the species responsible for conduction are the same. The scaling behavior of M /M max shows the temperature independent nature of relaxation time. The plot of normalized complex dielectric modulus and impedance as a function of frequency exhibits both short and long-range conduction in the film.

Research paper thumbnail of Ac-conductivity and dielectric relaxations above glass transition temperature for parylene-C thin films

HAL (Le Centre pour la Communication Scientifique Directe), 2012

ABSTRACT 45% semi-crystalline parylene-C (–H2C–C6H3Cl–CH2–)n thin films (5.8 μm) polymers have be... more ABSTRACT 45% semi-crystalline parylene-C (–H2C–C6H3Cl–CH2–)n thin films (5.8 μm) polymers have been investigated by broadband dielectric spectroscopy for temperatures above the glass transition (T g =90°C). Good insulating properties of parylene-C were obtained until operating temperatures as high as 200°C. Thus, low-frequency conductivities from 10−15 to 10−12 S/cm were obtained for temperatures varying from 90 to 185°C, respectively. This conductivity is at the origin of a significant increase in the dielectric constant at low frequency and at high temperature. As a consequence, Maxwell–Wagner–Sillars (MWS) polarization at the amorphous/crystalline interfaces is put in evidence with activation energy of 1.5 eV. Coupled TGA (Thermogravimetric analysis) and DTA (differential thermal analysis) revealed that the material is stable up to 400°C. This is particularly interesting to integrate this material for new applications as organic field effect transistors (OFETs). Electric conductivity measured at temperatures up to 200°C obeys to the well-known Jonscher law. The plateau observed in the low frequency part of this conductivity is temperature-dependent and follows Arrhenius behavior with activation energy of 0.97 eV (deep traps).

Research paper thumbnail of パラメータプロセスの制御による化学蒸着により堆積したパリレンDの化学的,物理的,および電気的性質の改善【Powered by NICT】

Materials Chemistry and Physics, 2017

Research paper thumbnail of Electroluminescence study of "on" and "off state breakdown in InP based HEMTs

Research paper thumbnail of Stuctural and dielectric study of parylene C thin films

HAL (Le Centre pour la Communication Scientifique Directe), Sep 1, 2009

International audienc

Research paper thumbnail of Dielectric relaxation study of amorphous of TiTaO thin films in a large operating temperature range

Research paper thumbnail of Structural and dielectric properties study of chlorinated and not chlorinated poly(p-xylylene)

HAL (Le Centre pour la Communication Scientifique Directe), Apr 1, 2010

International audienc

Research paper thumbnail of Propriétés diélectrique de couche mince de TiTaO

HAL (Le Centre pour la Communication Scientifique Directe), Mar 18, 2012

National audienc

Research paper thumbnail of Performance improvements of the hydrophobic and the dielectric properties of parylene C

Journal of Applied Physics, Oct 18, 2013

The increase in the hydrophobicity at the same time as the reduction in the dielectric properties... more The increase in the hydrophobicity at the same time as the reduction in the dielectric properties of an insulating material are the main factors necessary to improve the signal response of the electrowetting-on-dielectric and the organic field effect transistor electronic devices. Oxygen (O 2) and fluorine (CF 4) plasma treatments on 3.7 lm thicknesses-parylene C were carried out to understand the surface hydrophobicity character and their effect on the dielectric properties of the material. Fast hydrophobic recovery was observable during the first day after the O 2 treatment due to the reorientation of the polar polymer end chains to the bulk of parylene C. CF 4 plasma treatments reveal a noticeably increase of the hydrophobicity as the treatment time increases. Energy dispersive X-ray and Fourier transform infrared analyses have confirmed an increase in the number of fluorine containing CF x bonds where 1 x 3 after fluorine plasma treatments and after aging. The PPX C film treated with CF 4 plasma at 500 W for 30 min indicated the best hydrophobic character and the best dielectric properties due to the highest loading fluorine content in our experimental conditions. V

Research paper thumbnail of Improvement of chemical, physical, and electrical properties of parylene-D deposited by chemical vapor deposition by controlling the parameters process

Materials Chemistry and Physics, 2017

Surface and bulk properties of paryl ene D are sensitive to the T pyr and T sub. The sublimation ... more Surface and bulk properties of paryl ene D are sensitive to the T pyr and T sub. The sublimation temperature strongly affects the layer growth rate of parylene D. Nearly amorphous parylene-D is obtained when sublimation temperatures are height. Pyrolysis temperatures (T pyr) impact more the surface quality compared to the T sub. Dielectric properties are very sensitive to the parameter processes change.

Research paper thumbnail of Dielectric properties of parylene AF4 as low-k material for microelectronic applications

Thin Solid Films, 2012

Using dielectric spectroscopy analysis, three relaxation mechanisms have been identified in 60% s... more Using dielectric spectroscopy analysis, three relaxation mechanisms have been identified in 60% semi-crystalline parylene AF4 ([–F2C–C6H4–CF2–]n) fluoropolymers. At high temperature, fluorine species located at the electrode/polymer interface involve a space-charge polarization. β-Process assigned to local molecular motions of the C–F dipoles and the γ-relaxation due to local fluctuations of the F2C–C6H4 groups are also evidenced at intermediate and cryogenic temperatures

Research paper thumbnail of Microstructures électrostatiques de récupération d'énergie vibratoire pour les microsystèmes

Innovations technologiques

HAL - hal.archives-ouvertes.fr, CCSd - Centre pour la Communication Scientifique Direct. Accueil;... more HAL - hal.archives-ouvertes.fr, CCSd - Centre pour la Communication Scientifique Direct. Accueil; Dépôt: S'authentifier; S'inscrire. Consultation: Par domaine; Les 30 derniers dépôts; Par année de publication, rédaction, dépôt; Par type de publication; ...