Nondestructive DCIV method to evaluate plasma charging damage in ultrathingate oxides

Understanding and minimizing plasma charging damage to ultrathin gate oxide s become a growing concern during the fabrication of deep submicron MOS dev ices, Reliable detecting techniques are essential to understand its impact on device reliability, As the gate oxide thickness of MOST's rapidly scales down, the conventional nondestructive methods such as capacitor C-V and th reshold voltage and subthreshold swing of MOST's are no longer effective fo r evaluating this damage in gate oxide, In this paper, the new developed di rect-current current-voltage (DCIV) technique is-reported as an effective m onitor for plasma charging damage in ultrathin oxide. The DCIV measurements for p-MOST's with both 50- and 37-Angstrom gate oxides clearly show the pl asma charging damage region on the wafers and are consistent with the resul ts of charge-to-breakdown measurements, In comparing with charge-to-breakdo wn measurement and other conventional methods, the DCIV technique has the a dvantages of nondestructiveness, high sensitivity and rapid evaluation.