High Temperature Dielectric Properties of Polyimide/Boron Nitride Nanocomposites: Nanoparticle Size and Filler Content Effects

2015 ◽  
Vol 2015 (HiTEN) ◽  
pp. 000096-000099
Author(s):  
F. Saysouk ◽  
S. Diaham ◽  
M.-L. Locatelli
Keyword(s):  
High Temperature ◽  
Boron Nitride ◽  
Filler Content ◽  
Average Diameter ◽  
Dielectric Strength ◽  
Dc Conductivity ◽  
Nanocomposite Films ◽  
Breakdown Field ◽  
Leakage Currents ◽  
The One

An interesting way to improve high temperature polyimides (PI) electrical properties by filling it with boron nitride nanoparticles (BN) is proposed in this study. The filler content (from 0 to 60 vol.%) and the average diameter size (35 nm and 120 nm) of these nanoparticles have been varied. The preparation of the patented PI/BN nanocomposite films was performed following an optimized process in order to obtain a good dispersion of the nanoparticles in the films. The nanocomposite films were electrically characterized in the range 200–350 °C. In the case where the nanoparticles had the smallest size, the DC conductivity and leakage currents decreased from 4 to 6 orders of magnitude when the PI/BN films were compared to the neat PI films. The improvement of this property was obtained by a small amount of nanoparticles (1.6 vol.%). Results also show an increase in the dielectric strength of 1 MV/cm for a filler content of 42 vol.%. In the case where the nanoparticles had a larger size, a small improvement was seen on the DC conductivity and leakage currents. In contrast, the breakdown field was lower than the one of the neat PI, due to aggregate formation within the films.

Characterization of Silicone Gel for High Temperature Encapsulation in High Voltage WBG Power Modules

2017 ◽  
Vol 2017 (1) ◽  
pp. 000312-000317
Author(s):  
Adam Morgan ◽  
Xin Zhao ◽  
Jason Rouse ◽  
Douglas Hopkins
Keyword(s):  
High Temperature ◽  
Thermal Aging ◽  
Dielectric Strength ◽  
Material Structure ◽  
Power Module ◽  
Leakage Currents ◽  
Test Vehicle ◽  
Silicone Gel ◽  
Power Modules ◽  
Silicone Gels

Abstract One of the most important advantages of wide-bandgap (WBG) devices is high operating temperature (>200°C). Power modules have been recognized as an enabling technology for many industries, such as automotive, deep-well drilling, and on-engine aircraft controls. These applications are all required to operate under some form of extreme environmental conditions. Silicone gels are the most popular solution for the encapsulation of power modules due to mechanical stress relief enabled by a low Young's modulus, electrical isolation achieved due to high dielectric strength, and a dense material structure that protects encapsulated devices against moisture, chemicals, contaminants, etc. Currently, investigations are focused on development of silicone gels with long-term high-temperature operational capability. The target is to elevate the temperature beyond 200°C to bolster adoption of power modules in the aforementioned applications. WACKER has developed silicone gels with ultra-high purity levels of < 2ppm of total residual ions combined with > 200°C thermal stability. In this work, leakage currents through a group of WACKER Chemie encapsulant silicone gels (A, B, C) are measured and compared for an array of test modules after exposure to a 12kV voltage sweep at room temperature up to 275°C, and thermal aging at 150°C for up to more than 700 hours. High temperature encapsulants capable of producing leakage currents less than 1μA, are deemed acceptable at the given applied blocking voltage and thermal aging soak temperature. To fully characterize the high temperature encapsulants, silicone gel A, B, and C, an entire high temperature module is used as a common test vehicle. The power module test vehicle includes: 12mil/40mil/12mil Direct Bonded Copper (DBC) substrates, gel under test (GUT), power and Kelvin connected measurement terminals, thermistor thermal sensor to sense real-time temperature, and 12mil Al bonding wires to manage localized high E-Fields around wires. It was ultimately observed that silicone gels B and C were capable of maintaining low leakage current capabilities under 12kV and 275°C conditions, and thus present themselves as strong candidates for high-temperature WBG device power modules and packaging.

scholarly journals Synthesis of Boron Nitride Nanotubes by Self-Propagation High-Temperature Synthesis and Annealing Method

2010 ◽  
Vol 2010 ◽  
pp. 1-6 ◽  
Author(s):  
Jilin Wang ◽  
Yunle Gu ◽  
Laiping Zhang ◽  
Guowei Zhao ◽  
Zhanhui Zhang
Keyword(s):  
High Temperature ◽  
Boron Nitride ◽  
Average Diameter ◽  
Boron Nitride Nanotubes ◽  
Temperature Synthesis ◽  
High Temperature Synthesis ◽  
Effects Of Temperature ◽  
Temperature Time ◽  
Annealing Method ◽  
Bn Nanotubes

High-quality boron nitride nanotubes were synthesized by annealing porous precursor in flowing NH3gas at 1150°C. The porous precursor B18Ca2(MgO)9was produced by self-propagation high-temperature synthesis (SHS) method using Mg, B2O3, and CaB6as the starting materials, which played an important role in synthesis of BN nanotubes in large quantities. Samples were characterized by SEM, TEM, EDX, HRTEM, X-ray powder diffraction (XRD), Raman, and Fourier transform infrared (FTIR) spectroscopy. The as-synthesized BN nanotubes have an average diameter of about 150 nm with a wall/diameter ratio of 2/3. Mean length of the BN nanotubes was more than 10 μm. The effects of temperature, time, and the possible mechanism of the growth of the BN nanotubes were also discussed.

Enhancement of thermal stability and energy storage capability of flexible Ag nanodot/polyimide nanocomposite films via in situ synthesis

2020 ◽  
Vol 8 (36) ◽  
pp. 12607-12614 ◽  
Author(s):  
Shuang Xing ◽  
Zhongbin Pan ◽  
Xiaofeng Wu ◽  
Hanxi Chen ◽  
Xujiao Lv ◽  
...  
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Filler Content ◽  
Composite Films ◽  
In Situ Synthesis ◽  
Nanocomposite Films ◽  
Discharge Energy ◽  
Polyimide Nanocomposite ◽  
Discharge Energy Density

Composite films with an ultralow filler content of 0.1 vol% Ag-NDs exhibit an excellent high-temperature discharge energy density of 2.56 J cm−3, together with efficiency exceeding 80% at a temperature of 150 °C.

Characterization of Polyimide Dielectric Layer for the Passivation of High Electric Field and High Temperature Silicon Carbide Power Devices

2005 ◽  
Vol 483-485 ◽  
pp. 717-720
Author(s):  
Samir Zelmat ◽  
Marie Laure Locatelli ◽  
Thierry Lebey
Keyword(s):  
Silicon Carbide ◽  
High Temperature ◽  
Dielectric Strength ◽  
Junction Temperature ◽  
Breakdown Field ◽  
Power Devices ◽  
Metal Insulator ◽  
Metal Insulator Metal ◽  
Different Temperatures

Silicon carbide (SiC) is a wide bandgap semiconductor suitable for high-voltage, highpower and high-temperature applications [1]. However, and among other issues, the production of advanced SiC power devices still remains limited due to some shortcomings of the dielectric properties of the passivation layer [2]. Due to their supposed high operating temperature and dielectric strength [3], spin coated polyimide materials appear as a possible candidates for SiC device passivation and insulation purposes. As a matter of fact, they are already used in current commercial SiC devices allowing a maximum junction temperature of 175 °C. The aim of this paper is to study the ability of polyimide (PI) coatings to be used for a Tjmax up to 300 °C. Therefore, the main electrical properties (dielectric permittivity, leakage current and breakdown field) at different temperatures of a high temperature commercially available polyimide material (from HD Microsystems) in both Metal-Insulator-Semiconductor (MIS) and Metal-Insulator-Metal (MIM) structures are presented and discussed.

Assessment of Reliability of cap layers used in Cu-Black DiamondTM Interconnects

2003 ◽  
Vol 766 ◽  
Author(s):  
Ahila Krishnamoorthy ◽  
N.Y. Huang ◽  
Shu-Yunn Chong
Keyword(s):  
Dielectric Layer ◽  
Dielectric Breakdown ◽  
Copper Ions ◽  
Dielectric Strength ◽  
Time Dependent ◽  
Breakdown Field ◽  
Field Range ◽  
Time Dependent Dielectric Breakdown ◽  
Voltage Ramp ◽  
Low K

AbstractBlack DiamondTM. (BD) is one of the primary candidates for use in copper-low k integration. Although BD is SiO2 based, it is vastly different from oxide in terms of dielectric strength and reliability. One of the main reliability concerns is the drift of copper ions under electric field to the surrounding dielectric layer and this is evaluated by voltage ramp (V-ramp) and time dependent dielectric breakdown (TDDB). Metal 1 and Metal 2 intralevel comb structures with different metal widths and spaces were chosen for dielectric breakdown studies. Breakdown field of individual test structures were obtained from V-ramp tests in the temperature range of 30 to 150°C. TDDB was performed in the field range 0.5 – 2 MV/cm. From the leakage between combs at the same level (either metal 1 or metal 2) Cu drift through SiC/BD or SiN/BD interface was characterized. It was found that Cu/barrier and barrier/low k interfaces functioned as easy paths for copper drift thereby shorting the lines. Cu/SiC was found to provide a better interface than Cu/SiN.

Crystallization effect on the dielectric strength of fluorinated parylene at high temperature

2012 ◽  
Vol 15 (2-3) ◽  
pp. 157-168 ◽  
Author(s):  
Mireille Bechara ◽  
Rabih Khazaka ◽  
Sombel Diaham ◽  
Marie-Laure Locatelli ◽  
Pierre Bidan
Keyword(s):  
High Temperature ◽  
Dielectric Strength ◽  
Crystallization Effect

scholarly journals Multi-Scale Minero-Chemical Analysis of Biomass Ashes: A Key to Evaluating Their Dangers vs. Benefits

2021 ◽  
Vol 13 (11) ◽  
pp. 6052
Author(s):  
Paola Comodi ◽  
Azzurra Zucchini ◽  
Umberto Susta ◽  
Costanza Cambi ◽  
Riccardo Vivani ◽  
...  
Keyword(s):  
Raw Materials ◽  
Average Diameter ◽  
Rietveld Analysis ◽  
Fly Ashes ◽  
Amorphous Content ◽  
Multi Scale ◽  
Italian Law ◽  
Polycyclic Aromatic ◽  
Mineralogical Study ◽  
The One

A multi-methodic analysis was performed on five samples of fly ashes coming from different biomasses. The aim of the study was to evaluate their possible re-use and their dangerousness to people and the environment. Optical granulometric analyses indicated that the average diameter of the studied fly ashes was around 20 µm, whereas only ~1 vol% had diameters lower that 2.5 µm. The chemical composition, investigated with electron probe microanalysis, indicated that all the samples had a composition in which Ca was prevalent, followed by Si and Al. Large contents of K and P were observed in some samples, whereas the amount of potentially toxic elements was always below the Italian law thresholds. Polycyclic aromatic hydrocarbons were completely absent in all the samples coming from combustion plants, whereas they were present in the fly ashes from the gasification center. Quantitative mineralogical content, determined by Rietveld analysis of X-ray powder diffraction data, indicated that all the samples had high amorphous content, likely enriched in Ca, and several K and P minerals, such as sylvite and apatite. The results obtained from the chemo-mineralogical study performed make it possible to point out that biomass fly ashes could be interesting materials (1) for amendments in clayey soils, as a substitution for lime, to stimulate pozzolanic reactions and improve their geotechnical properties, thus, on the one hand, avoiding the need to mine raw materials and, on the other hand, re-cycling waste; and (2) as agricultural fertilizers made by a new and ecological source of K and P.

scholarly journals Boron nitride nanoplatelets as two-dimensional thermal fillers in epoxy composites: new scenarios at very low filler loadings

2020 ◽  
Vol 40 (10) ◽  
pp. 859-867
Author(s):  
Yao Shi ◽  
Genlian Lin ◽  
Xi-Fei Ma ◽  
Xiao Huang ◽  
Jing Zhao ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Boron Nitride ◽  
Filler Content ◽  
Hexagonal Boron Nitride ◽  
Filler Loading ◽  
Epoxy Composites ◽  
General Phenomenon ◽  
Sudden Drop ◽  
Reduced Graphene ◽  
Thermal Conducting

AbstractHexagonal boron nitride (h-BN) nanoplatelets (0.6 μm in diameter and 100 nm in thickness) are introduced into epoxy resin to improve the polymer’s thermal conducting ability. As expected, the thermal conductivities (TCs) of the composites, especially the in-plane TCs, are significantly increased. The in-plane TC of the epoxy composites can reach 1.67 W/mK at only 0.53 wt% loading, indicating h-BN nanopletelets are very effective thermal fillers. However, after carefully studied the correlation of the TC improvement and filler content, a sudden drop of the TC around 0.53 wt% filler loading is observed. Such an unexpected decrease in TC has never been reported and is also found to be consistent with the Tg changes versus filler content. Similar trend is also observed in other 2-D nanofillers, such as graphene oxide, reduced graphene oxide, which may indicate it is a general phenomenon for 2-D nanofillers. SEM results suggest that such sudden drop in TC might be coming from the enrichment of these 2-D nanofillers in localized areas due to their tendency to form more ordered phase above certain concentrations.

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