This paper presents a resistance self-biased inverse class-F23 voltage-controlled oscillator (VCO). The VCO keeps ultra-low amplitude and phase mismatches by inducing a resistance between primary and secondary coils of the transformer. It also induces both 2nd and 3rd harmonic resonances to reduce 1/f3 corner frequency. The VCO is designed in 40nm CMOS with frequency range of 12.1GHz to 16.5GHz. It achieves -118dBc/Hz and -109dBc/Hz at 1MHz offset frequency at 12.1GHz and 16.5GHz respectively, whose 1/f3 corner frequency is 54kHz and 20kHz. The power consumption of the VCO is 14.3mW at 1.1V supply. The core area is 0.03mm2.