By: David Kanter (dkanter.delete@this.realworldtech.com), April 23, 2015 10:19 am
Room: Moderated Discussions
Wouter Tinus (wouter.tinus.delete@this.gmail.com) on April 21, 2015 11:08 pm wrote:
> Interesting read David, and kudos for publicly going out on a limb on this.
>
> I don't quite understand the QWFET though. What exactly is the quantum effect? The focus of the text seems
> to be on the way charge is carried through the channel, but the transistor design in Figure 1 makes me
> think that the magic is more in the way that charge is transferred to and from it, with that whole complicated
> InAlAs/Si/InP hamburger that the gate is embedded in. It also looks like the InGaAs is a uniform layer
> on the wafer, so I suppose there should also be a mechanism that prevents substrate leakage.
The quantum part of it is explained in the article and has to do with the dimensions of the InGaAs channel relative to the 'quantum neighborhood' of the electrons. Note that the electron is confined into the channel by the barrier layer below and the gate above.
> The QW-FinFET design makes a lot more sense to me, though I can't reconcile the four-side
> containment with the earlier statement that the quantum well is formed when the charge carriers
> act as if they are in a 2-dimensional configuration. This looks way more like a traditional
> semiconductor, so that again makes me wonder what exactly makes it quantum.
>
> Thanks in advance for anyone who can clarify :)
As a few other posters have mentioned, the definition is a bit fuzzy.
David
> Interesting read David, and kudos for publicly going out on a limb on this.
>
> I don't quite understand the QWFET though. What exactly is the quantum effect? The focus of the text seems
> to be on the way charge is carried through the channel, but the transistor design in Figure 1 makes me
> think that the magic is more in the way that charge is transferred to and from it, with that whole complicated
> InAlAs/Si/InP hamburger that the gate is embedded in. It also looks like the InGaAs is a uniform layer
> on the wafer, so I suppose there should also be a mechanism that prevents substrate leakage.
The quantum part of it is explained in the article and has to do with the dimensions of the InGaAs channel relative to the 'quantum neighborhood' of the electrons. Note that the electron is confined into the channel by the barrier layer below and the gate above.
> The QW-FinFET design makes a lot more sense to me, though I can't reconcile the four-side
> containment with the earlier statement that the quantum well is formed when the charge carriers
> act as if they are in a 2-dimensional configuration. This looks way more like a traditional
> semiconductor, so that again makes me wonder what exactly makes it quantum.
>
> Thanks in advance for anyone who can clarify :)
As a few other posters have mentioned, the definition is a bit fuzzy.
David
