28nm high-k metal gate RRAM with fully compatible CMOS logic processes

Abstract

A new 2-transistor logic ReRAM cell with 28nm high-k metal gate (HKMG) and fully CMOS logic compatible process is reported. The new 28nm logic compatible RRAM cell consists of two logic standard high-k metal gate CMOS transistors by an optimized composite resistive gate dielectric film TiN/HfO2/TiN as a storage node in the cell and as a gate dielectric in the select transistor. Using the cell gate as a source line for RRAM set/reset operation, the resistive memory states can be read and sensed by the selection of the select transistor and its bitline. As a result, the new 2-transistor CMOS logic ReRAM cell is very area-saving, cost effective, and fully compatible with advanced high-k metal gate CMOS logic technology platform. By adapting the highly manufacturable high-K gate dielectric in embedded ReRAM cell, the cell does not need any additional deposition of the resistive film or extra process steps, as a result, it will be easily scaled down and following by the CMOS technology evolution, besides it can be simply dropped on a logic IP or circuits for the need of NVM array or discrete storages in advanced SOC logic-NVM applications.