2024 Nanotech L2

Moore's law …

• tells that number of transistors double every year on a chip.
• is based on classical physical rules.
• was fullfilled by using the same geometry of FET.
• described an exponential improvement of chip performance.

Field Effect Transistor

• is the basic building block of CMOS chip production.
• has a conducting channel attached to 3 contacts.
• is produced from metalic ingredients.
• reached a size on 1nm in CMOS mass production.

Tri-gate transistor

• increased the leakage current between source and drain.
• required HfOx ALD dielectric.
• reduced the number of transistors on a chip.
• changed the CMOS design from lateral to 3D structures.

Moore's law is dying, since …

• fabs that make the most advanced chips are becoming prohibitively pricey.
• there is no company which could follow the predicted trend.
• the CMOS technology reached fundamental physical limitations.

Nanotechnology

• is a multidiciplinary field including physics, chemisty and biology.
• was overadvertised around 2000, but has no influence on science today.
• started with the realization Scanning Electron Microscope.
• focuses on objects which are smaller than 1μm.

Avogadro number gives a conversion factor

• of volume change between macro and nano worlds.
• of linear scale change between macro and nano worlds.
• of surface dimensions between macro and nano worlds.

What is smaller a FET transistor or a typical virus?

• FET transistor
• virus

Which lithography technique has the best resolution?

• Optical lithography.
• Electron beam lithography.
• Scanning probe lithography.

In the Drude model

• electrons move with a drift velocity due to backscattering.
• electrons scatter on the atoms of the lattice.
• the wire length should be smaller than L_e.
• the current voltage relation deviates from Ohm's law.

Spintronics devices

• require ballistic conductor.
• need a shorter channel length than spin relaxation length.
• are not in real application.
• are based on phase coherent effects.