55NM Ultra-Low-Power Platform 3.3V I/O Device Reliability Improvement

The demand of Ultra-Low-Power (ULP) chips is increasing gradually with the development of intelligent society. ULP chips are widely used in Bluetooth and WIFI. In order to further expand the application scenarios, we developed 3.3V I/O device based on Huali-55nm ULP platform by adjusting the gate oxide thickness and implant (IMP) conditions (source, angle, energy and dosage). Then, a series of process optimizations were performed to achieve a high reliability level for the 3.3V I/O device. The Hot Carrier Injection (HCI) Direct Current (DC)
$\mathrm{t}_{0.1\%}$
lifetime of NMOS and PMOS can reach 0.63year and 24.5year respectively (DC criteria is 0.2year), while Negative Bias Temperature Instability (NBTI) DC t
0.1
% lifetime can reach 127year (DC criteria is 5year).