Reverse electric field

For higher pressures, very little resonance is seen as electron collisions occur so frequently that the electron cannot be turned by the magnetic field in time to catch the reversing electric field. At lower pressures, there is a strong resonance. 

One of the components of an electromagnetic wave is a rapidly reversing electric field (E). This field alternately stretches and compresses a polar bond, as shown in Figure 12-3. When the electric field is in the same direction as the dipole moment, the bond is compressed and its dipole moment decreases. When the field is opposite the dipole moment, the bond stretches and its dipole moment increases. If this alternate stretching and compressing of the bond occurs at the frequency of the molecule s natural rate of vibration, energy may be absorbed. Vibrations of bonds with dipole moments generally result in IR absorptions and are said to be IR-active. 

Modulated Reverse Electric Field Copper Metallization for High Density Interconnect and Very Large Scale Integration Applications... 

While electrodeposited copper represents considerable promise for HDI and VLSI applications, simple insertion of the additive chemistry or PRC processes developed for PTHs application are not likely to be successful. Furthermore, while new additive chemistries may initially be successful, the extreme tolerances and associated control issues, impurity incorporation, and waste associated with CMP prohibit the chemistry-only approach. By considering the fundamental differences associated with the PTH and HDI as well as VLSI applications, we have developed a modulated reverse electric field process (MREF) for copper electrodeposition. In contrast to the long cathodic duty cycle-short anodic duty cycle used in the PRC process, the MREF process consists of a short cathodic duty followed by a long anodic pulse. By tuning the frequency and the cathodic to anodic charge ratio (Qc/Qa), conformal and filling capability are demonstrated for vias and trenches in the 0.5 to 100 pm size range. 

The engine industry is pursuing the use of bipolar electric loading to enhance the mechanical actuation of piezo or PZT stacks or actuators for fuel injection. Theoretically, a reverse electric field at a limited level can introduce beneficial depolarization and increase the number of switchable domains. Hence, a greater piezoelectric response of a stack can be promoted. This is mainly based on tests of singlelayer PZT and limited work on several commercial PZT stacks However, the fatigue performance of PZT stacks under the bipolar electric loading mode, specifically semi-bipolar mode, is essentially uncharacterized. 

The thinner the ferroelectric layer is. the better il can fulfill the thermal diffusion. If it becomes thirmer than 0.1 pm in order, the hysleresia characteristic will worsen (9). The polarizatioo reverses by applying reverse electric field over the coercive electric field. Figure 9 shows the temperature dependence of the pyroelectric constant P, of 52/ 48 copolynur under a bias field (10). The decrease of the coetdve field with increasing... 

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