A high f/sub OSC//fT ratio VCO in SiGe BiCMOS technology

A 37-GHz voltage controlled oscillator (VCO) fabricated in IBM's 47-GHz SiGe BiCMOS technology is presented. The VCO achieves a phase noise of -81dBc/Hz at 1-MHz offset from the carrier while delivering an output power of -30dBm to 50 /spl Omega/ buffers. Drawing 15-mA of dc current from a 3-V power supply the VCO occupies 350μm×280μm of silicon area. Capacitive emitter degeneration and compact layout are used to achieve high f/sub OSC//f
_T
ratio.