2.5 /spl Omega///spl square/ W/TiN/poly stack gate technology for high density and embedded DRAM technology

Abstract

A W/TiN/Poly gate stack has been developed and extensively characterized, and it is applied to a 0.2 /spl mu/m CMOS transistor design for Gigabit and embedded DRAM technology. The gate sheet is less than 2.5 /spl Omega///spl square/ with a 600 /spl Aring//200 /spl Aring//900 /spl Aring/ W/TiN/Poly gate stack at 0.16 /spl mu/m line width. The effective oxide thickness is found to be 3 /spl Aring/ thicker than a comparable poly-only gate. The oxide hard breakdown field can exceed 12 MV/cm and CHC lifetime is greater than 10 years with the W/TiN/Poly gate stack technology. In addition, a drive current of 400 /spl mu/A//spl mu/m for nMOS and 190 /spl mu/A//spl mu/m for pMOS have been achieved at 1 pA//spl mu/m off-current and 1.8 V Vcc with 5 nm gate oxide. This is the highest drive current reported to date for similar technologies.