A W-band injection-locked frequency doubler in 65-nm CMOS is proposed. By using the coupled resonator, a 69.2-94.6-GHz locking range has been achieved with a 3.4- ~ 4.1-dBm injected power. The second-order harmonic current is injected from the top of the resonator, which avoids the source degeneration issue. The measured phase-noise deterioration from that of the injected signal at 100-kHz offset is only 6.2 dB, which is close to the theoretical calculation. The doubler occupies a die area of 0.16 mm2, including the buffers, and draws 9.7- ~ 11.4-mA current from a 1.0-V power supply excluding the buffers.