1.5 nm equivalent thickness Ta/sub 2/O/sub 5/ high-k dielectric with rugged Si suited for mass production of high density DRAMs

A 1.5 nm equivalent thickness Ta/sub 2/O/sub 5//rugged Si capacitor is demonstrated for mass production of high density DRAMs (Dynamic Random Access Memories). More than 10 years breakdown lifetime of CVD-TiN/Ta/sub 2/O/sub 5//rugged Si capacitor is experimentally clarified for the first time. An excellent pause refresh property is confirmed by using 0.40 mm/sup 2/ DRAM cell as well. This system is applicable to a 0.16 mm/sup 2/ cell for production.