Publication
VLSI Technology 2019
Conference paper

Self-Allancd Gate Contact (SAGC) for CMOS technology scaling beyond 7nm

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Abstract

We demonstrate a novel self-aligned gate contact (SAGC) scheme with conventional oxide/nitride materials that allows superior process integration for scaling while simplifying the SRAM cross-couple wiring. We show that the key feature to avoid both gate-contact (CB) to source-drain local interconnect (LI) shorts and the LI-contact (CA) to gate shorts is the shape of the LI cap. A trapezoid-shaped oxide (SiO2) LI cap with an appropriate taper angle eliminates shorting between the contacts in the gate and source-drain region. We further demonstrate that this oxide LI cap is fully compatible with Cobalt (Co) metallization with a novel selective tungsten (W) growth process. Additionally, this process enables the SRAM cross-couple (XC) in the same metallization level, eliminating the need for an upper level wiring and greatly simplifying routing in the SRAM cell.

Date

01 Jun 2019

Publication

VLSI Technology 2019

Authors

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