A New Direct Measurement Method of Time Dependent Dielectric Breakdown at High Frequency

A novel technique is presented for a direct evaluation of oxide breakdown under AC stress at high frequencies up to 500MHz. It relies on a RF setup, which combines a high speed pulse generator, transition converters and $50\Omega $ termination probes, to deliver to the device a digital AC signal without overshoot and distortion. The method leads to similar results than a complex on-chip solution while offering more simplicity and flexibility. Time Dependent Dielectric Breakdown (TDDB) in 28nm Fully Depleted Silicon On Insulator (FDSOI) transistors is then characterized under DC and AC stress at various frequencies. It follows a power law with frequency TDDB $\alpha \text{F}^{\mathbf {a}}$ with a ≈0.3, allowing an extended lifetime to circuits operating at GHz frequency.