3nm Chips Don't Have 3nm Features

I was on a call with my friend Marlo when I learned something that broke my mental model of chip manufacturing: nothing on a "3nm" chip measures 3 nanometers. The name is pure marketing.

It Wasn't Always Like This

For 35 years, process names meant something. Intel's 0.5µm process in 1993 had 0.5µm gate lengths.

This broke in 1997. Intel's "0.25µm" process had 0.20µm gates. Their "0.18µm" process had 0.13µm gates. Marketing took over.

By 28nm, the name had no relation to any physical dimension. Not gate length, not metal pitch, not gate pitch.

What's Actually on a "3nm" Chip

• Gate pitch: 48-54nm
• Metal pitch: 21-28nm
• Fin pitch: 25-30nm

Smallest features: around 10-12nm. Although 10nm is scale is impressive, it's nowhere near 3nm in reality. WikiChip has the detailed breakdown.

Why Does This Persist?

Smaller number = better public perception. TSMC says 3nm. Samsung says 3nm. Nobody blinks first. Intel tried honesty in 2021. Their "10nm" became "Intel 7". Still playing the game, just different numbers. IEEE Spectrum argues we should drop nanometer naming entirely.

Next time you see "2nm" or "1.4nm", remember: it's branding. The engineering is real. The scale is not.