[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?

[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.

[williadc]

Noise rejection is another important advantage of CMOS. I don't know enough about these materials to know whether it applies here or not.

[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.

[kabouseng]

Dwolb's explanation isn't quite clear, and I tried to type an explanation as well, but the wiki page has a vastly better explanation as to the advantages of CMOS over NMOS.

http://en.wikipedia.org/wiki/NMOS_logic