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The capacitor device has evolved from a simple device to an innovative and complex device. The capability of a capacitor is very much dependent on capacitance performance. Currently, researchers have shown interest in hybrid composites, which are capable of improving performance and increase reliability of devices. Thus, there is a need to fabricate thin films of hybrid dielectric materials such as polymer (PVDF-TrFE) and ceramic (PbTiO3). This study presents the preparation of the PVDF-TrFE layer for bilayer composite PbTiO3/PVDF-TrFE configured as metal–insulator–metal films capacitor. The deposition process utilised two methods: solvent casting and spin coating. The ceramic layer (first layer), PbTiO3, has optimum dielectric permittivity and tangent loss of about 138 and 0.9 taken at 1 kHz. The polymeric spin-coated layer (second layer) PVDF-TrFE films produced good dielectric property as compared to solvent casting prepared films. This provides an opportunity for further investigation of the dielectri...

This study examines the dielectric properties of filled PVDF film and filled PVDF-TrFE film incorporated with 1, 3, 5, and 7 weight percentages of magnesium oxide (MgO) nanofillers. The metal-insulator-metal (MIM) configuration demonstrates PVDF/MgO with 7 weight percent of MgO which produced high dielectric constant (1 kHz) with low dielectric loss. The ATR-FTIR spectra of PVDF/MgO (7%) indicate wide bonding peaks at 840 cm-1 and 880 cm-1, assigned to -CH2 and -CF2 groups, respectively. This implies the presence of high content of β-crystals in the PVDF/MgO (7%) film. A shift in the peak was observed in the same film, from 1170 cm-1 to 1180 cm-1 suggesting possible transformation from γ-crystals to β-crystals. This film showed no apparent defect on its film surface. Thus, it established that PVDF incorporated with 7% MgO can be used to produce nanocomposite thin film for low-frequency electronic devices.

The impact of surface plasma modification on PVDF-TrFE film with different exposure time was investigated using X-ray photoelectron spectroscopy (XPS). The main emphasis of this study was to optimize the exposure time of argon plasma on the surface of PVDF-TrFE films The surface of spin coated PVDF-TrFE film was modified with argon plasma at exposure time of 1, 3, 5, 7 and 9 min/s. Prior to modification, only small amount of atomic percent (1.92 %) of O1s peak was observed at 540.8 eV, but upon modification, the atomic percent for O1s peak was found to increase to 8.8 %. Meanwhile, the atomic percent for F1s peak observed at 695.3 eV was found to decrease from 70.6 % to 61.2 %. This phenomenon is an indication that plasma modified PVDF-TrFE films were readily oxidized. Importantly, most of the fluorine elements were removed from the modified PVDF-TrFE film surface, which rendered the film favourable for adhesion with other material for coating aplications.

Poly (vinylideneflouride)/nanomagnesium oxide (PVDF/MgO) film with MgO loading percentage of 7% were annealed with various annealing temperatures ranging from 70°C to 170°C. The PVDF/MgO(7%) thin films were fabricated using spin coating technique with metal-insulator-metal (MIM) configuration and the dielectric constant of PVDF/MgO(7%) with respect to annealing temperatures was studied. The PVDF/MgO nanocomposite thin films annealed at temperature of 70°C (AN70) showed an improvement in the dielectric constant of 27 at 103 Hz compared to un-annealed sample (UN), which is 21 at the same frequency. As the annealing temperatures were increased from 90°C (AN90) to 150oC (AN150), the dielectric constant of PVDF/MgO(7%) were found to gradually decreased from 25 to 12 respectively, interestingly lower than the UN thin films. AN70 also produced low value of tangent loss (tan δ) at frequency of 103 Hz. The resistivity value of AN70 was also found to increase from 3.08×104Ω.cm (UN-PVDF) to 1.05×105Ω.cm. The increased in dielectric constant, with low tangent loss and high resistivity value suggests that 70°C was the favourable annealing temperature for PVDF/MgO(7%) for application in electronic devices such as low frequency capacitor.

The enhancement of ferroelectric and dielectric properties of PVDF-TrFE by incorporating various percentages of Magnesium Oxide (1 – 7%) for spin coated nanocomposite thin film was demonstrated. Observations showed uniform distribution and low agglomeration of MgO in the PVDF-TrFE nanocomposite thin film, especially for 3% MgO. Additionally, the 3% MgO incorporated into PVDF-TrFE had generated the highest Pr (88 mC/m2) and dielectric constant (13.6) in comparison other percentage compositions. However, the addition of more than 3% MgO filler loading caused a reduction in the ferroelectric and dielectric properties of the nanocomposite thin films.

Metal-insulator-metal (MIM) capacitors based on lead titanate (PbTiO3) nanofilms were prepared using a novel method involving modified spin coating onto the bare electrodes of a coated glass. Different solutions were prepared by adding different concentrations of lead acetate (PbAc) powder to improve the electrical properties of the PbTiO3 films. The nanofilms were characterized in terms of their surface morphology, dielectric properties, and current-voltage characteristics. Physical and dielectric properties are related to the increased PbAc content in the films prepared within the range of 5-25 wt.%. The films with 10 wt.% PbAc provide acceptable dielectric permittivity, low loss factor, and improved capacitance density at frequencies lower than 100 kHz. Low leakage current densities and high resistivity behavior can be obtained at approximately 10(-7) A cm(2). Therefore, the resultant films are suitable for MIM capacitor applications and exhibit potential for memory storage applications.

This study investigates the effect of annealing on the topography, morphology and crystal phases of poly(vinylideneflouride)/Magnesium Oxide (MgO) nanocomposites thin films via AFM, FESEM and ATR-FTIR. The nanocomposites thin films were annealed at temperatures ranging from 70°C to 170°C. The annealed PVDF/MgO nanocomposites thin films were then cooled at room temperature before removal from the oven. This is to restructure the crystal lattice and to reduce imperfection for the PVDF/MgO nanocomposites thin films. PVDF/MgO nanocomposites thin films with annealing temperatures of 70°C, 90°C and 110°C showed uniform distribution of MgO nanoparticles, relatively low average surface roughness and no visible of defects. High application of annealing temperature on PVDF/MgO nanocomposites thin films caused tear-like defects on the thin films surface as observed by FESEM. The PVDF/MgO nanocomposites thin films annealed at 70°C was found to be a favourable film to be utilized in this study due to its enhanced β-crystalites of PVDF as evident in ATR-FTIR spectra.

Th is study presents the resistivity behavior of PbTiO3 thin films which were prepared towards metal-insulator-metal capacitor device fabrication. The PbTiO3 thin films were prepared through sol-gel spin coating method that involved various deposition parameters that is (1) different molar concentration of PbTiO3 solutions, (2) various additional PbAc-content in PbTiO3 solutions, and (3) various annealing temperature on PbTiO3 thin films. Hence, an electrical measurement of current versus voltage was done to determine the resistivity behavior of PbTiO3 thin films.Th is study presents the resistivity behavior of PbTiO3 thin films which were prepared towards metal-insulator-metal capacitor device fabrication. The PbTiO3 thin films were prepared through sol-gel spin coating method that involved various deposition parameters that is (1) different molar concentration of PbTiO3 solutions, (2) various additional PbAc-content in PbTiO3 solutions, and (3) various annealing temperature on PbTiO3 thin films. Hence, an electrical measurement of current versus voltage was done to determine the resistivity behavior of PbTiO3 thin films.

This study presents the investigation on crystallinity property of PbTiO3 thin films towards metal-insulator-metal capacitor device fabrication. The preparation of the thin films utilizes sol-gel spin coating method with low annealing temperature effect. Hence, structural and electrical characterization is brought to justify the thin films consistency.

Innovative advance dielectric materials were utilized to fabricate novel thin film capacitor device. This includes ceramic and polymeric material combination which is considered to enhance the dielectric polarization. The dielectric film presented in the study focused on PbTiO3/PVDF-TrFE which was prepared through layer-by-layer spin coating deposition method. The PVDF-TrFE coating was aimed to encapsulate the fragility and to improve the crystallinity property of PbTiO3 thin film surface. The preferential orientation of (1 0 1) tetragonal perovskite PbTiO3 was obtained in this and high crystallinity was found on bilayered PbTiO3/PVDF-TrFE film. The bilayered film produced good film surface in term of its uniformity and surface roughness. The er and tan (δ) value of bilayered PbTiO 3 / PVDF-TrFE film was taken at 1 kHz that approximately 220 and 0.09 respectively.

Poly(vinylidene flouride)/nano-magnesium oxide (PVDF/MgO) nanocomposites with MgO loading percentage of (7% wt. %) were annealed with various annealing temperatures ranging from 70°C to 170°C with rapid removal from the oven. From dielectric constant, the samples annealed at temperature of 70°C showed an improvement in the dielectric constant from 21 to 23 at frequency 103 Hz for UN and AN70 respectively. However, as the temperatures were increased, the dielectric constant of PVDF/MgO (7%) was found to decrease. XRD showed the presence of β-phase for PVDF/MgO(7%) sample annealed at 70°C in comparison to unannealed sample, hence PVDF/MgO(7%) film is suitable to be used for low frequency capacitor application.

This study investigates the plasma surface modified spin coated PVDF-TrFE (70/30) film of 200nm thick using Atomic Force Microscopy (AFM), Water Contact Angle (WCA) and Fourier Transform Infrared Spectroscopy (FTIR). The surface of the spin coated PVDF-TrFE film were modified using 13.56 MHz rf Argon plasma. The exposure time of the charged particle on PVDF-TrFE films were varied for 1, 3, 5, 7 and 9mins. Prior to modification, the average surface roughness observed was 3.5nm. However upon modification, the surface roughness was increased to 9.5nm. The contact angle of the surface modified film was reduced from 89° to 58°. The increase in surface roughness and wettability of the modified film provided good biocompatibility. This finding created great interest in developing functional polymer suitable for applications in areas such are biomedical, bio-analytical assays, textile and even food industry.

The annealing temperature for 250nm PVDF-TrFE (70:30 mol %) spin coated thin films were varied at solvent evaporation (Ts = 79°C), Curies transition (Tc= 113°C) till melting temperature (Tm = 154°C). From the XRD measurement, there was an improvement in the crystallinity of the annealed films, consistent with the increased in the annealing temperatures. Morphological studies of the annealed PVDF-TrFE thin films as observed with Field Emission Scanning Electron Microscope (FESEM) (100k magnification), showed enhanced development of elongated crystallite structures better known as ferroelectric crystal. However, the AN160 thin film showed fibrous-like structure with appearance of nanoscale separations, which suggested to posed high possibility of defects. Ferroelectric characterization indicated an improvement in the remnant polarization of annealed PVDF-TrFE thin films with the exception to AN160 in which leakage of current was inevitable due to the presence of cracks on the film surface.

The different morphology of 250 nm PVDF-TrFE (70:30 mol%) thin films were observed in relation to its ferroelectricity. The annealing temperatures were varied from solvent evaporation (Ts), Curies transition (Tc), up to melting temperature (Tm). It was found that the annealing process promoted the development of elongated crystallite structure also known as ferroelectric crystal, which significantly improved the ferroelectric properties of PVDF-TrFE (70:30 mol%) thin films. However, the presence of nanoscale separations on the thin film annealed over Tm (AN160) suggested high possibility of defects, and hence a reduction in ferroelectric properties of thin films.

In this study, we investigated the effect of MgO nanofiller content to the dielectric layer properties of nano-MgO film. Nano-MgO film was successfully deposited with particle size in the range of 42 to 92 nm by simple chemical solution technique. The film produced shows some surface modification as the nanofiller content increased. With the nanofiller loading increasing from 0 wt% to 3 wt%, relative permittivity values were varied. NanoMgO films with 1 wt% filler content have high relative permittivity value while film with 2 wt% was good in morphology.

Poly (vinylideneflouride)/nanomagnesium oxide (PVDF/MgO) nanocomposites with MgO loading percentage of 7% were annealed with various annealing temperatures ranging from 70oC to 170oC. The PVDF/MgO(7%) thin films were fabricated using spin coating technique with MIM structure. The dielectric constant of PVDF/MgO(7%) was studied over a wide range of annealing temperatures with rapid removal from the oven once the annealing was utilized. The nanocomposites thin films annealed at temperature of 70oC (AN70) shows an improvement in the dielectric constant of 23 at 103 Hz compared to unannealed sample (UN), which was 21 at the same frequency. However, as the annealing temperatures were increased from 90oC (AN90) to 170o C (AN170), the dielectric constant of PVDF/MgO(7%) were found to decrease from 16 to 7 respectively, which were lower than the UN thin films. AN70 also produced low value of tangent loss at low frequency˼˰˸̱̈́̾˰δ˹˰̴̷̹̹̳̱̹̾̈́̾˰̸̱̈́̈́˼˰̵̷̱̱̼̹̾̾̾˰̱̈́˰temperatures 70oC is favourable temperature used to improve the dielectric constant of PVDF/MgO(7%).

The annealing temperature for 250 nm PVDF-TrFE (70:30 mol %) spin coated thin films were varied at solvent evaporation (Ts = 79 °C), Curies transition (Tc= 113 °C), till melting temperature (Tm = 154 °C). XRD measurement showed that, there was an improvement in the crystallinity of the annealed films, consistent with the increased in the annealing temperatures. Morphological studies of the annealed PVDF-TrFE thin films as observed with Field Emission Scanning Electron Microscope (FESEM) (100k magnification), showed enhanced development of elongated crystallite structures known as ferroelectric crystal. However, thin film annealed at 160 °C (AN160) showed fibrous-like structure with appearance of nanoscale separations, which suggested high possibility of defects. Ferroelectric characterization indicated an improvement in the remnant polarization of annealed PVDF-TrFE thin films with the exception to AN160 in which leakage of current was inevitable due to the presence of cracks on the film surface.

This study investigates the effect of varying loading percentages of MgO on the topography and morphology of Poly (vinylideneflouride)/Magnesium Oxide (PVDF/MgO) nanocomposites thin films. PVDF/MgO nanocomposites spin coated thin films with thicknesses ranging from 200nm to 456nm were successfully characterized. The nanocomposite solutions were spin coated on Al-glass substrates at 1500rpm. The topography and surface roughness of PVDF/MgO nanocomposites were characterized by using AFM. FE-SEM was used to investigate the surface morphology of the nanocomposites thin films and ATR-FTIR was used to determine the chemical bonding of PVDF/MgO nanocomposites. MgO (7%) was found to be the optimum loading percentage for PVDF/MgO nanocomposite film with favorable distribution of MgO particles, minimum defects and high content of β-phase as evident by FESEM and FTIR.

The annealing temperature of 250nm PVDF-TrFE (70:30 mol%) spin coated thin films were optimized. The annealing temperature were varies starting from solvent evaporation (Ts), Curies transition (Tc), up to melting temperature (Tm). The result shows that the dielectric constant increases with the increasing of annealing temperature. Supported with the XRD observation indicating there were an improvement in crystallinity consistently with the increasing of the annealing temperature. Morphological properties of the annealed PVDF-TrFE thin films were observed by utilizing Field Emission Scanning Electron Microscope (FESEM) at 100k magnification. It can be found that, the annealing temperature promotes the development of elongated crystallite structure which known as ferroelectric crystal. However, the presence of nanoscale cracks on the thin film annealed at 160°C (AN160, over Tm) suggesting high possibility to posed defects while in device applications.

This study investigates the surface properties of plasma surface modified spin coated PVDF-TrFE (70/30) film using Atomic Force Microscopy (AFM), Water Contact Angle (WCA) and X-ray Photoelectron Spectroscopy (XPS). The surfaces of the spin coated PVDF-TrFE film were modified using 13.56 MHz rf Argon plasma. The exposure time of the charged particle PVDF-TrFE films were varied for 1, 3 and 5mins. Prior to modification, the average surface roughness obtained was 8.615nm, but upon modification, the surface roughness was found to increase to 12.466nm. The value of the contact angle of the modified film was reduced from 90o to 43o and the XPS analysis showed dehydrofluorination of PVDF-TrFE films surfaces. The improved in surface roughness and the increased in wettability of the modified film, resulted in good biocompatibility of the modified PVDF-TrFE thin films. This phenomenon has created interest in researchers for developing functional polymer used for applications in areas such are biomedical, bio-analytical assays, textile and even food industry.

This paper reports on the dielectric properties of multilayer PVDF-TrFE/PMMA:TiO2 thin film. Two samples were fabricated on ITO substrates; one with PVDF-TrFE only and another PMMA:TiO2 on PVDF-TrFE on (PVDF-TrFE/PMMA:TiO2). Both samples were produced by spin coating method. Dielectric properties were characterized using impedance spectroscopic. Dielectric constant, k, capacitance and dielectric loss, tan δ values of PMMA:TiO2/PVDF-TrFE were measured in the frequency range 0 – 50 kHz. The result for dielectric loss did not show any significant different between the samples with and without nanocomposite PVDF-TrFE layer. However, the dielectric constant are affected when depositing a nanocomposite PVDF-TrFE layer on PMMA:TiO2. The dielectric constant is decreased by 0.3 from 7.9 to 7.6.

Multilayer ZnO/MgO was successfully deposited using sol-gel spin coating method at different MgO molar concentration. The electrical and dielectric properties of deposited multilayer films were investigated using two point probes I-V measurement and impedance spectroscopy respectively. The resistivity was calculated based on I-V curve obtained and the results show that there is increment in resistivity values from 1.04 x 105Ω.cm to 7.45 x 105Ω.cm as the MgO concentration varied from 0.2M to 1.0M. The growth of multilayer films was measured in term of their thickness using surface profiler. Moreover from the observation, the value of dielectric constant, k is decrease when the MgO concentrations increase due to non-uniform and porous structure in the films. This is proven by their surface morphology observed by field emission scanning electron microscopy, FESEM. There is also interesting view obtained in this work where the surface morphology of multilayer film with 0.2M and 0.4M MgO concentration produced nano-flower and nano-rod like structure respectively.

Problem statement: The attachment of biopolymers such as collagen on inert polymeric template created great challenge due to hydrophobic nature of polymeric material. The modification of PVDF for improved adhesion and introduction of specific functionalities have been widely recognized in various industrial applications. Typical methods for modifying polymer surface such as chemical etching and UV irradiation are not favorable as it requires high temperature and the use of chemical solvents. However plasma modification is suitable as it utilizes low heat and a clean environment, thus preventing contamination on the deposited collagen. Approach: Free standing orientated Poly (Vinylidene Fluoride) (PVDF) films were fabricated by solution casting method and dried in a convention oven. The dried PVDF films were orientated in a tensile machine at temperature 70°C enclosed in a custom made environmental chamber. The pulling rates of 5 mm min-1 were utilized with a draw ratio of 2 (R = Lfinal/Linitial). The PVDF film was plasma treated for 60 sec to enhance the hydrophilic property of PVDF and utilized as template for collagen deposition. The deposited collagen on surface of PVDF was left in desiccators at temperature of 24°C for complete drying. Results: The untreated and plasma-treated PVDF template were observed for water contact angle measurement, the functional group and dielectric properties of collagen were observed and measured by FTIR and SOLARTRON respectively. Conclusion: The orientated PVDF films were produced at pulling speed of 5 mm min-1 and temperature of 70°C. The hydrophobic PVDF surface was transformed to a hydrophilic surface by plasma treatment for collagen deposition. The FTIR result shows the overlapping peaks of C-H and C-F in range 1500-1000 cm-1 which indicates the C-C bonding of collagen and PVDF. The significant increase in dielectric constant is a result from the favorable bonding between collagen and PVDF template.

Development of high performance capacitor is reaching towards new generation where the ferroelectric materials take places as the active dielectric layer. The motivation of this study is to produce high capacitance device with long life cycle. This was configured by preparing bilayered films where lead titanate as an active dielectric layer and stacked with the top dielectric layer, poly(vinyledenefluoride-trifluoroethylene). Both of them are being referred that have one in common which is ferroelectric behavior. Therefore the combination of ceramic and polymer ferroelectric material could perform optimum dielectric characteristic for capacitor applications. The fabrication was done by simple sol-gel spin coating method that being varied at spinning speed property for polymer layers, whereas maintaining the ceramic layer. The characterization of PVDF-TrFE/PbTiO3 was performed according to metal-insulator-metal stacked capacitor measurement which includes structural, dielectric, and ferroelectric measurement.

This research work investigates the ferroelectric characteristic of nanostructured ZnO/MgO bilayer based MFIM capacitor. The low leakage current (10−8 A.cm−2) of nanostructured ZnO/MgO bilayer films were observed for all annealed bilayer films. Nanostructured ZnO/MgO bilayer film annealed at 475°C was then utilized as insulator (dielectric) layer in the fabrication of MFIM capacitor due to its high resistivity (7.15×104 Ω.cm) and low leakage current density (10−8 A.cm−2). The optimized nanostructured ZnO/MgO bilayer film was proven to act as a stable buffer layer for the PVDF-TrFE in where the P-E loop can withstand for the applied voltage up to 190V. The polarization-field (P-E) hysteresis revealed high electrical strength of ZnO/MgO/PVDF-TrFE MFIM capacitor.

Hybrid composited material like polymer-ceramic will improve the reliability factor of the device. Yet, the motivation still goes on to produce high performance device. In this study, the impedance analysis on bilayer films lead titanate and poly(vinyledenefluoride-trifluoroethylene) yield to the semicircle cole-cole plot with added slanted spike results. This presents the double layer capacitance which occurred between dielectrc-electrode. The bilayer films obtains about ∼105Ω which determines the films are high resistive dielectric material. The bilayer films were fabricated at maximum of 105 nm thickness on top of electrode coated glass substrate. Structural property of bilayer films obtain distinguish behavior compared to the single layer films. Moreover, the line profile observed on each layer presents low surface roughness for bilayer prepared films. Thus, this study highlights the importance of bilayer films denoted for capacitor application.

—Poly (vinylideneflouride)/nano-magnesium oxide (PVDF/MgO) film with 7% MgO loading percentage was annealed at various annealing temperatures ranging from 70°C to 150°C. The PVDF/MgO thin film was fabricated using spin coating technique with a metal-insulator-metal (MIM) configuration. The dielectric and electric properties of PVDF/MgO with respect to annealing temperatures was studied. The PVDF/MgO nanocomposites thin films annealed at temperature of 70°C (AN70-PVDF/MgO) showed an improvement in the properties; dielectric constant value of 26 at 1 kHz frequency compared to un-annealed sample (UN-PVDF/MgO), which is 21 at the same frequency. As the annealing temperatures were increased from 90°C (AN90) to 150°C (AN150-PVDF/MgO), the dielectric constant values were found to gradually decreased from 25 to 12 respectively, which was lower than the UN-PVDF/MgO thin films. AN70-PVDF/MgO also produced relatively low tangent loss (tan δ). The resistivity value of AN70-PVDF/MgO was also found to increase from 3.08x104 Ω.cm (UN- PVDF/MgO) to 4.55x104 Ω.cm. The increased in the dielectric constant, with low tangent loss and high resistivity value suggests that 70°C was the favorable annealing temperature for PVDF/MgO film suitable for the application in electronic devices such as low frequency capacitor.

Development of innovative device design was fully utilized to fabricate hybrid composited PVDF-TrFE/PbTiO 3 that having bilayered films capacitors. Step by step of layer deposition trough spin coating method had performed an optimal thickness of ∼ 319 nm PbTiO 3 first layer and ∼470 nm polymer second layer. It was found that averagely 55.6 nm multigrain size of PbTiO 3 performed high densification films with minimal porosity behaviour. Thus, the co-polymer layer plays important role to cover up the porosity and as well as the stiffness of the PbTiO 3 first layer with membrane like structured films. The dielectric measurement of the bilayered films showed the reduction of dielectric constant at low frequency compared to the PbTiO 3 single layer, however, contrary effect on tangent loss (tan (δ)) measurement. The equivalent capacitance value of both films configuration showed some interest where the significant consideration of series capacitance effect on bilayered films could be ignored. Therefore, to the best of our known, the significant of this study is to investigate dielectric and structural property of nanoscaled device using hybrid combination of polymer/ceramic having bilayered composition based metal-insulator-metal capacitors.

The use of high dielectric material for thin films capacitor has been known since the first ferroelectric materials were introduced. The capability to store large energy density would be the ideal criteria to pursue nanoscaled films capacitor applications. Nowadays, capacitor device becomes complex device rather than just focus at single function where ferroelectric material get involves. In this study, lead based titanate thin films ceramic will be fabricated by sol-gel spin coating method with typical multicoating layers to investigate the ferroelectric, dielectric properties, and capacitance characteristic. The measurements were based on 100 kHz and 1 MHz frequencies application which there's lies the significant finding of the dielectric materials property. Other, like surface profiler (KLA Tencor) is used as films thickness measurement that reports under 200nm thickness. PbTiO 3 metal-ferroelectric-metal device is going to be prepared by involves the indium tin oxide coated glass as substrate, whereas Al metal will be deposited as top electrode through thermal evaporator method.

Magnesium oxide and bilayer ZnO/MgO dielectrics film were successfully deposited using spin coating technique. The effect of MgO layer thickness towards prepared dielectric films behaviour was determined by controlling the deposition time. The comparison of the MgO and ZnO/MgO dielectrics film properties shows that the bilayer ZnO/MgO with 238nm MgO layer thickness shows better dielectrics properties compared to others. This was due to its small surface roughness which resulted in better electrical properties that have high resistivity and low leakage current. Optimized bilayer ZnO/MgO film was then used as the dielectrics film for fabrication of organic capacitor. Capacitor performance was determined via capacitance-voltage (C-V) analysis at different frequency applied and it revealed that, the capacitance value increased from 2.4pF to 10pF with addition of PVDF-TrFE organic ferroelectric layer on bilayer ZnO/MgO film caused by high polarization produced in the film.

This work present the synthesis of ZnO/MgO multilayer films using spin coating technique with different MgO layer thickness which are 171nm, 238nm and 506nm. The influence of MgO thickness on the insulating layer properties was investigated. The best prepared insulating layer to be used as dielectrics was found to be ZnO/MgO film deposited using 238 nm MgO layer. This is due to it uniformity, low porosity, high resistivity (28.7 × 105 Ω.cm) and low leakage current (below 1E-7). The particle produced also in nanometer dimension which in the range of 42 to 84 nm that will lead to the improvement in the device characteristic.

This study investigates the effect of varying loading percentage of MgO on the dielectric constant of Poly (vinylideneflouride)/Magnesium Oxide (PVDF/MgO) nanocomposite thin films. PVDF/MgO nanocomposite spin coated thin films were successfully fabricated and characterized. PVDF and nanocomposites solutions with loading percentage of MgO at 3, 5, 7, 9, and 11% were spin coated on Al-glass substrates at 1500rpm. The optimum percentage of PVDF/MgO thin film obtained from the dielectric measurement was 7%. The dielectric constant of PVDF/Mg(7%) nanocomposite at frequency 103 Hz was 21, with low dielectric loss and absence of visible film defects, as evident by FE-SEM images. In FTIR, broad bonding peaks at 840 and 880 cm−1 can be observed. Both bonding represented the -CH 2 and -CF 2 groups of PVDF, which indicated high β-phase content that attributed to the increment in the dielectric constant of PVDF/MgO(7%) nanocomposite. The PVDF/MgO(7%) nanocomposite is favorable for low frequency electronic application such as capacitor.

The morphology of PVDF-TrFE (70/30) thin film at various annealing temperature were investigated using non-contact mode Atomic Force Microscopy (AFM). Differential Scanning Calorimetry (DSC) technique was used to obtain T C , T m , and T Crys of PVDF-TrFE. The prepared spin coated PVDF-TrFE (70/30) thin films were annealed at T C (113°C), T m (154°C), T Crys (135°C) and T c at cooling (55°C) in accordance to the DSC thermogram observed. Impedance Spectroscopy were conducted to study the dielectric characteristic of the thin films in order to substantiate the electrical behavior of the thin films From the results obtained, the thin films exhibited different morphologies depending on the annealing temperatures utilized. Formation of needle-like crsytallite structure was observed film annealed at and over T m . Thin film re-crystallized at T C has an optimized dielectric constant of ∼7.8 at 104 hz.

This paper investigates the effect of PVDF-TrFE layer to the electrical properties of MIS device. The MIS (Al/PMMA:TiO2/PVDF-TrFE/Si) structures were fabricated on n-type Si substrate. The results indicate that the properties of MIS improved drastically with PVDF-TrFE layer. I-V and C-V characteristics shows that the MIS has a fast operating voltage approximately 1 V, low leakage current, large capacitance. No hysteresis was observed compared to MIS without PVDF-TrFE layer. The improvement in the electrical properties of MIS (Al/PMMA:TiO2/PVDF-TrFE /Si) is due to the increment in the real permittivity, e' value of the insulator.

Magnesium oxide, MgO with nanometre dimension particles size (36 to 73 nm) was successfully deposited on cleaned glass substrate. The drying temperatures were varied from 100 to 300°C and the dielectrics behaviour was investigated. From the results, it was revealed that variation of nano-MgO films properties obtained by changing the drying temperature. Nano-MgO film dried at 200°C was found to be a good dielectric layer due to it structural properties that resulted in the enhancement of relative permittivity value. The electrical properties shows better in dielectric layer characteristic where the resistivity was found to be 12.8 × 104 Ω.cm with leakage current density of 10−9 A.cm−2. The ZnO/MgO-based organic capacitor was fabricated and the remnant polarisation obtained was in range of 59 to 69 mC/m2 with capacitance value of 40 pF.