A Nanotechnology Enhancement to Moore's Law

Table 2

Key future nanotechnologies.

Device	Applications	Advantages	Disadvantages
3D transistor	Logic element	Small size	Will still face tunneling effect issue.
	Memory	Low power	Clock tree routing.
Spintronics	Memory	Small size	Control of magnetic field versus spin-polarized current.
	Logic element	Low power	Drivability.
Carbon nanotube FET/graphene	Logic element	Ballistic transport (high speed)	Placement of nanotubes/graphene in a circuit is difficult and not yet production.
		Small size	Control of electrical properties of carbon nanotube (size, chirality) difficult and not yet stably achieved.
Single-electron transistors (SET)	Logic element		Sensitive to background charge instability.
		Small size; Low power	High resistance and low drive current.
			Cannot drive large capacitive (wiring) loads.
			Requires geometries 10 nm for room-temperature operation.
Quantum dot (quantum cellular automata, QCA)			Multiple levels of interconnection across long distance difficult.
			Room-temperature operation difficult.
	Logic element	Small size	New computation algorithms required.
			Method of setting the initial state of the system not available.
			Single defect in line of dots will stop propagation.
DNA computing	Logic element	High parallelism	Imperfect yield.
			General-purpose computing not possible.
Quantum computing	Logic element	High computing speed for some certain problem	The coherence in some highly promising concepts for qubits will disappear after about a second. Moreover, the smaller the qubits the faster that process occurs. The information exists may not be long enough to be processed.