2021年8月4日，本课题组刘志伟同学发表IEEE Journal of the Electron Devices Society文章一篇。纪志罡教授为通讯作者。这篇文章基于新型铁电非易失性存储器，探索了与TDDB相关的可靠性问题，介电击穿（TDDB）问题与存储器的实际工作情况紧密相关，本文探讨了不同击穿条件下潜在的机制，提出击穿过程的物理图像并验证了影响其击穿特性的关键点，最后提出了如何解除这一限制因素可能的方法，对未来TDDB的改善提供了新的思路。

Investigation of Time Dependent Dielectric Breakdown (TDDB) of Hf0.5Zr0.5O2-based Ferroelectrics Under Both Forwardand Reverse Stress Conditions

Z.Liu; P.Cai; S.Yu; L.Han;; R.Wang; P.Ren and Z.Ji*

Abstract:

Increasing demands for mass storage and new paradigm computing ask for non-volatile memories that can meet reliability requirements. Hf0.5Zr0.5O2-based (HZO) memory has attracted growing attention due to its excellent CMOS compatibility. This letter investigated the time dependent dielectric breakdown (TDDB) of HZO ferroelectric under both forward and reverse stress conditions, which is relevant to the memory’s practical operation. The key similarities and the differences for both breakdown conditions have been identified and the underlying mechanism is explored. It is found that the pre-existing oxygen vacancies near the bottom electrode play the key role and all the observed phenomenon can be explained. Therefore, the precise control of these pre-existing oxygen vacancies can be critical for future TDDB improvement.