Characteristics of HfZrOx gate stack engineering for reliability improvement on 28nm HK/MG CMOS technology

High-K/Metal-Gate (HK/MG) reliability TDDB and BTI are investigated systematically for the first time through HfZrO
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gate stack engineering. To meet reliability requirements, it is shown that the HK film thickness, the position and concentration of a Zr dopant, utilizing post deposition anneal (PDA), and decoupled plasma nitridation (DPN) are important factors.