Reliability study under DC stress on mmW LNA, Mixer and VCO

A reliability study under DC stress has been conducted on a low noise amplifier (LNA), a mixer and a voltage controlled oscillator (VCO). Both mmW blocks were designed with heterojunction bipolar transistor (HBT) 0.13μm SiGe process from STMicroelectronics. Regarding simulations and HBT degradation studies, DC stresses were defined to provide HBT degradation within the mmW blocks. S parameters were characterized for the LNA; conversion gain and low frequency noise (LFN) were measured for the mixer; oscillation frequency and phase noise were respectively characterized and simulated. LNA and mixer are designed for 77 GHz automotive radar applications and the VCO is designed for 60 GHz wHDMI standard. Limited degradations on mmW blocks characteristics were observed for significant stress conditions covering a time to fail (TTF) of 10years.