http://www.physorg.com/news72114043.html
of ferroelectric materials hold promise for many applications.
[QUOTE] Lamperts law of barrier layer capacitance predicts a non-ohmic behavior for insulators films. The law he developed, and I found to be correct, is that the law is complex, being initaially ohmic then following, a square law I^2 dependence and with thickness following again the ohmic law. As stated, in attempting to obtain bulk double injection in lasers, following the work of Basov in chalcogenides, I found the law true. The trouble is that if one follows that to the end, our present sub-micron FETs will never work. But they do. We are very lucky. I have never seen the follow on from the FET people who undoubtedly have this in hand, and keep it as proprietary technology. wbw
Someday Mergatroid will live ...! Trudge onward! ye soldiers of quantum physics. 
Tunneling is exactly how gate dielectrics leak.
It can be enhanced by electric field or thermal energy (field and thermionic emission, respectively).
It can be enhanced by electric field or thermal energy (field and thermionic emission, respectively).
QUOTE (guiding_light+Jul 19 2006, 01:06 AM)
Tunneling is exactly how gate dielectrics leak.
It can be enhanced by electric field or thermal energy (field and thermionic emission, respectively).
Do you think that is the way tunnel diodes work? w.[QUOTE]
It can be enhanced by electric field or thermal energy (field and thermionic emission, respectively).
Do you think that is the way tunnel diodes work? w.[QUOTE]
The paper on tunneling across a thin film of ferroelectric junction appears to have some inconsistencies. First, is the fact that in the Schottky barrier layer theory, thin films of insulators are capabe of carrying large currents, following a cube law VI dependence. Tunneling would appear not to be necessary. Second, it is not published, but in thin, small particle,[QUOTE] ferroelectrics like BaTiO3, the ferroelectric property disappears, and the structure becomes isotropic*. The effect is common in other materials as well. In such instances it is not clear that the material remains anisotropic and posseses ferroelectic characteristics. Third, it is not clear what the contacts were, since if they were just forming a barrier layer capacitnce, the effect could be interpreted as tunneling and even having diode charactristics.
I presume that these points have been indeed covered and that the authors have verified that these arguments are not applicable. *Patented. D.C. =2000. wbw
The new work at Nebraska is a significant advance and is very interesting over that of the early our first work attempted in the '60s. They are correct, in that advanced device development may result from their work.
WBWilson.
QUOTE (wbraxtonwilson+Aug 10 2006, 01:27 PM)
Do you think that is the way tunnel diodes work? w.
It is just how dielectric tunneling works
I'd be interested to see this theory.
Besides tunneling, there is also space-charge current to consider.
It is just how dielectric tunneling works
QUOTE
Lamperts law of barrier layer capacitance predicts a non-ohmic behavior for insulators films. The law he developed, and I found to be correct, is that the law is complex, being initaially ohmic then following, a square law I^2 dependence and with thickness following again the ohmic law. As stated, in attempting to obtain bulk double injection in lasers, following the work of Basov in chalcogenides, I found the law true. The trouble is that if one follows that to the end, our present sub-micron FETs will never work. But they do. We are very lucky. I have never seen the follow on from the FET people who undoubtedly have this in hand, and keep it as proprietary technology. wbw
I'd be interested to see this theory.
Besides tunneling, there is also space-charge current to consider.
Tunnel diodes: Current flows because the insulating region is thin, like in any tunnel effect. >30 years ago, heavy doping could be used to obtain automatically (though not easily...) a thin depleted zone in a PN junction, showing Tunnel effect. In contrast, it's more recent that insulation layers can be made thin enough to obtain - or be plagued by - tunnel effect.
Any low-voltage Zener diode is in fact a tunnel diode, where avalanche effect isn't important. It's quite logical since it needs several eV to produce a new pair in silicon. Consistently with the absence of avalanche, low-voltage "Zener" diodes make little noise (far less than a bandgap reference, hence useful and used) but have a soft I-V curve.
The diodes usually called Tunnel have (had) one special use: due to misalignment of their bands, their forward current drops with increasing forward voltage (within certain narrow limits, yes). Since this negative dynamic resistance is really fast, the diode was used as an oscillator. At a few GHz, so it's outfashioned now. Have a look at Wiki.
Thin ferroelectric material: What about PVDF?
Promises of ferroelectric components: I'm still waiting! In 1989 or even sooner, people already wanted to make nonvolatile Ram of them. Ramtron still exists, but makes 4kb chips in 2007...
Any low-voltage Zener diode is in fact a tunnel diode, where avalanche effect isn't important. It's quite logical since it needs several eV to produce a new pair in silicon. Consistently with the absence of avalanche, low-voltage "Zener" diodes make little noise (far less than a bandgap reference, hence useful and used) but have a soft I-V curve.
The diodes usually called Tunnel have (had) one special use: due to misalignment of their bands, their forward current drops with increasing forward voltage (within certain narrow limits, yes). Since this negative dynamic resistance is really fast, the diode was used as an oscillator. At a few GHz, so it's outfashioned now. Have a look at Wiki.
Thin ferroelectric material: What about PVDF?
Promises of ferroelectric components: I'm still waiting! In 1989 or even sooner, people already wanted to make nonvolatile Ram of them. Ramtron still exists, but makes 4kb chips in 2007...
And in a thin film, preferably between two metals:
What current density is possible without material wearing?
I don't care whether it's tunnel, thermoemission or voodoo. I want something damned fast and nonlinear.
What current density is possible without material wearing?
I don't care whether it's tunnel, thermoemission or voodoo. I want something damned fast and nonlinear.
Still looking for an answer!
What current density is possible by tunnel effect in a MIM without material wearing?
What current density is possible by tunnel effect in a MIM without material wearing?
QUOTE (Enthalpy+Jul 5 2007, 09:22 PM)
Still looking for an answer!
What current density is possible by tunnel effect in a MIM without material wearing?
Enthalpy needs to defeat entropy. That's all. WBW
What current density is possible by tunnel effect in a MIM without material wearing?
Enthalpy needs to defeat entropy. That's all. WBW
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