@User This freely available paper from 2013 has a nice comparison of the race to highest frequencies for 130nm. Their design wins at 10GHz: https://www.researchgate.net/profile/Changzhi_Li2/publication/221373930_A_Regulated_31-106_GHz_Linear_Dual-Tuning_Differential_Ring_Oscillator_For_UWB_Applications/links/565dc1bc08ae4988a7bced73.pdf