I used the term "punchthrough" to refer to the merging of the drain and source depletion regions, so you're correct...the transistor essentially looks like a resistor (plus all the parasitic capacitances and source/drain diodes)
The increased speed of the double gate mosfet is due to it's behaving as if it's twice as WIDE (doubling the current driving capability), not twice as LONG (which would decrease transconductance for a given gate width). Longer devices are not as prone to drain-source punchthrough, which is a mechanism by which transistors can be stuck "on", so I suppose it is in this sense that the device exhibits the behavior of a longer transistor. In browsing the comments to this posting I was surprised at the general lack of knowledge concerning the incorporation of research results into products. Where does everyone think the price cuts across almost all consumer electronic product categories come from? Have you opened up a CD player from 1988 and compared it to one from 1998? Sure, they sound the same, but that's the point: a very large amount of research is required to pack the same features and performance into products that sell for less and less. The complexity of a cell phone far exceeds that of many products that do something which seems more "cutting edge" (like the latest video accelerator card), yet many service providers give them away free.
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I used the term "punchthrough" to refer to the merging of the drain and source depletion regions, so you're correct...the transistor essentially looks like a resistor (plus all the parasitic capacitances and source/drain diodes)
I'm not certain, but I think the name of the cartoon was "The Daffy Doc", made in 1938. So Daffy agrees that 'foo' is pretty old.
The increased speed of the double gate mosfet is
due to it's behaving as if it's twice as WIDE (doubling the current driving capability), not twice as LONG (which would decrease transconductance for a given gate width). Longer devices are not as prone to drain-source punchthrough, which is a mechanism by which transistors can be stuck "on", so I suppose it is in this sense that the device exhibits the behavior of a longer transistor.
In browsing the comments to this posting I was surprised at the general lack of knowledge concerning the incorporation of research results into products. Where does everyone think the price cuts across almost all consumer electronic product categories come from? Have you opened up a CD player from 1988 and compared it to one from 1998? Sure, they sound the same, but that's the point: a very large amount of research is required to pack the same features and performance into products that sell for less and less. The complexity of a cell phone far exceeds that of many products that do something which seems more "cutting edge" (like the latest video accelerator card), yet many service providers give them away free.