학술논문

Improving Ge-rich GST ePCM reliability through BEOL engineering
Document Type
Conference
Source
ESSDERC 2021 - IEEE 51st European Solid-State Device Research Conference (ESSDERC) Solid-State Device Research Conference (ESSDERC), ESSDERC 2021 - IEEE 51st European. :231-234 Sep, 2021
Subject
Components, Circuits, Devices and Systems
Photonics and Electrooptics
Resistance
Performance evaluation
Microscopy
Memory management
Europe
Reliability engineering
Germanium
ePCM
reliability
BEOL
28nm FDSOI
embedded memory
emerging memory
Ge-rich GST
GST
Language
Abstract
This paper discusses the effect of back-end of line (BEOL) process on cell performance for a Phase-Change Memory embedded in a 28nm FD-SOI platform (ePCM). The impact of BEOL is first shown by describing the microscopic evolution of the active Ge-rich GST alloy during process. Ge clustering has been proven to occur during the fabrication process, impacting the pristine resistance and the after forming cell performance. Two different BEOL processes are then benchmarked in terms of key performance. An optimized process is then identified, and an extensive electrical characterization of array performance and reliability is performed on the full 16MB chip. The optimized BEOL process results in a memory cell fully compatible with the requirements for demanding automotive applications.