millimeter-wave (mm-wave) IC

Integrated circuits operating where the radio wavelength shrinks to millimetres — roughly 30 to 300 GHz. At 60 GHz a full wavelength is just 5 mm, comparable to the chip itself, so the very wires on the die behave like transmission lines and antennas, and lumped intuition breaks down. This band is the home of 5G FR2 (24–47 GHz), automotive radar (77 GHz), and emerging 6G research, prized because the enormous available bandwidth allows multi-gigabit links.

The appeal — vast bandwidth and tiny antennas you can pack into a phased array — comes with brutal physics: free-space path loss soars with frequency, transistor gain and efficiency fall, and even the on-chip wiring leaks energy. Designers respond with beamforming arrays of many small elements that electronically steer a focused beam to claw back the lost power, and with advanced nodes (FinFET, SiGe BiCMOS) whose transistors still have gain at these frequencies. mm-wave is where RFIC design becomes inseparable from electromagnetics.