Electric breakdown

Electrons (emA sec) 8500 Holes (emA sec) 400 Breakdown Electric Field (V/cm) 4x10 Dielctric constant 12.8 Maximum Junction Temperature (°C) 300... 

The electrical properties of materials are important for many of the higher technology applications. Measurements can be made using AC and/or DC. The electrical properties are dependent on voltage and frequency. Important electrical properties include dielectric loss, loss factor, dielectric constant, conductivity, relaxation time, induced dipole moment, electrical resistance, power loss, dissipation factor, and electrical breakdown. Electrical properties are related to polymer structure. Most organic polymers are nonconductors, but some are conductors. 

For high-frequency devices, the breakdown electric field strength is not as important as the saturated drift velocity. In SiC, this is 2 x 10 cm/sec [5, 6], which is twice that of Si. A high-saturated drift velocity is advantageous in order to obtain as high-channel currents as possible for microwave devices, and clearly SiC is an ideal material for high-gain solid-state devices. 

Diamond has a number of properties, such as wide band gap, high breakdown electric field, and low dielectric constant, which make it an ideal candidate for semiconductor applications. Why has diamond not been used more often in semiconductor applications ... 

Resistance of plasma-polymerized films with respect to electric breakdown can be quite high. This resistance increases at relatively low specific powers of the non-thermal discharges applied for polymer film deposition. As an example, plasma-polymerized fluorocy-clobntane film is characterized by breakdown electric fields 5 10 V/cmforafihnthickness of 150 nm, 6 10 V/cm for a film thickness of 100 nm, and 7-8 10 V/cmforafihnthickness of 75 nm. To compare, breakdown of a conventional PTFE film with thickness 0.1-... 

Breakdown Electric Field (V/cm) 3x105 4x105 5xl0 1x10 ... 

Overall, we have systematically studied PVDF-based co- and terpolymers to tune its polarization profile for capacitor applications. The desirable terpolymer (VDF/TrFE/CTFE = 65.6/26.7/7.7), exhibiting a high dielectric constant (e 60) at the Curie temperature (35°C), shows a high breakdown electric field >500 MV/m, high energy density (releasing >13 J/cm ), relatively small energy loss, and almost no remnant polarization at zero electric field. 

Figure 1.6 shows the electric field breakdown voltage of air as a function of the pressure-separation distance product. It shows that at large values of pressure-distance product, the breakdown electric field strength is approximately equal to 30 kV/cm. At small values of this product, the breakdown electric field strength increases significantly. This phenomenon is due to the rarefaction effect. When the mean free path becomes comparable to... 

Silicon carbide has favorable properties such as a wide bandgap, high thermal conductivity, high breakdown electric field strength, and high thermal stabihty. It... 

The other important semiconductor material parameter required for analysis of the and BFOM is the mobility. Because the electron mobility is larger than that of holes, it is relevant to consider only n-type drift regions. A comparison of the mobility of electrons in the three SiC polytypes (6) with that in silicon is provided in Fig. 3. In general, the mobilities in SiC are lower than those in silicon, offsetting some of the benefits of the higher breakdown electric field sttength. 

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