

Move Over, Silicon, There’s a New Circuit in Town - jcr
http://viterbi.usc.edu/news/news/2014/june-17-2014.htm

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_up
Sound great could be a breaktrough for curved sensors too.

> [http://spectrum.ieee.org/tech-
> talk/semiconductors/devices/so...](http://spectrum.ieee.org/tech-
> talk/semiconductors/devices/sony-creates-curved-cmos-sensors-that-mimic-the-
> eye)

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jcr
I hate the title. I used the original title since I couldn't think of anything
better. Suggestions?

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zyx321
HN policy is to always use the original title, no matter how dreadfully
sensationalist or inaccurate it is.

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jcr
Actually, we're supposed to fix the really bad (misleading or linkbait)
original titles but without injecting our own opinions (i.e. editorializing).

[http://ycombinator.com/newsguidelines.html](http://ycombinator.com/newsguidelines.html)

> _" Otherwise please use the original title, unless it is misleading or
> linkbait."_

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ssdfsdf
Why is it important to have both n-type and p-type transistors in the same
circuit, why not just use p type carbon nanotube transistors?

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Dwolb
It has to do with small amounts of leakage current on the device level. If you
just use 1 type of transistor (p or n -type) then when you change from on/off
or off/on you will lose more current than if you use both types in your
circuit. Sum this across billions of transistors and the equation starts to
make sense.

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RollAHardSix
Can you explain what the importance of this leakage is? Electricity costs
'power-wise' it makes sense but are there other reasons to want to avoid
transistor leakage?

Disclaimer: Not a hardware guy but am utterly fascinated, ooh's and ahh's may
spontaneously result.

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Dwolb
I'll speak to this a bit...

Transistor logical state, typically logical 1 or logical 0, is represented
physically by positive and negative charges, respectively. Therefore, we can
change the device logical output of 1 or 0 by changing the charge output as
positive or negative.

However, to change the charge of a piece of metal from positive to negative
(or neutral to negative... it doesn't matter because we're worried about
relative change), you need to physically move electrons (charge) on or off the
metal. This movement of charge is real 'work' if you're unable to fully
recover the charge when the device changes state. This results in spent
energy.

Leakage current is important to consider mainly for power and heat transfer.
As we require devices to increase computing performance and decrease power
consumption, it is important to use techniques that economically reduce power.
As power consumption of a chip increases, the spent energy of a toggling
transistor becomes heat that needs to be removed in order to ensure proper
functionality (in the worst case, the chip burns itself up). Therefore, proper
thermal simulation and validation must be made at the system level (depending
on what type of designer you are).

