Improvement in the Cumulative Failure Distribution of High-k Dielectric Subjected to Nanoscale Stress by D-2 Post-Deposition Annealing

[[abstract]]By taking advantage of the small contact area of the conductive atomic force microscopy (CAFM) tip with the sample surface, and the powerful measurement capability of the semiconductor parameter analyzer, a nanoscale stress was applied to the atomic-layer-deposited (ALD) HfO2 high-k dielectrics prepared with N-2, D-2, and no post-deposition anneal (PDA), respectively. The statistical breakdown behavior of ALD HfO2 under nanoscale stresses was determined and is presented in this paper. It is evident that the cumulative failure distribution of breakdown voltage of high-k dielectrics under nanoscale CVS basically follows the Weibull statistics. We also found that the ALD HfO2 prepared with D-2 PDA showed an obvious improvement in cumulative failure distribution when compared with those prepared with N-2 PDA and no PDA. The result indicates that D, PDA can substantially suppress the generation of defects during the application of nanoscale stress and improve the reliability of high-k dielectrics. (C) 2009 The Japan Society of Applied Physics[[note]]SC