Effects of Hot-Carrier Stress on the RF Performance of a 0.18-μm MOS Divide-by-4 LC Injection-Locked Frequency Divider

Abstract

The effect of ac hot-carrier stress on the performance of a wide locking range divide-by-4 injection-locked frequency divider (ILFD) is investigated. The ILFD was implemented in the TSMC 0.18 μm 1P6M CMOS process. The ILFD uses direct injection MOSFETs for coupling external signal to the resonators. Radio frequency (RF) circuit parameters such as oscillation frequency, tuning range, phase noise, and locking range before and after RF stress at an elevated supply voltage for 5 h have been examined by experiment. The measured locking range, operation range and phase noise after RF stress shows significant degradation from the fresh circuit condition.