How small have microchips gotten, and is there a limit?

The answer

The transistors on modern chips have shrunk from 10 micrometers in 1971 to as small as 3 nanometers today - smaller than a single strand of DNA (which is about 2.5 nm wide). TSMC and Samsung now manufacture 3nm chips with over 50 billion transistors. However, as we approach atomic scales, quantum effects like electron tunneling cause current to leak through barriers that should be solid. The industry is exploring solutions including gate-all-around transistors, 3D chip stacking, and entirely new materials like carbon nanotubes to continue miniaturization.