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Title: Depolarization Field Induced Instability of Polarization States in HfO 2 Based Ferroelectric FET
Doped HfO2 based ferroelectric FET (FeFET) exhibits a greatly improved retention performance compared with its perovskite counterpart due to its large coercive field, which prevents domain flip during retention. In this work, however, through extensive temperature dependent experimental characterization and modeling, we are demonstrating that: 1) with FeFET geometry scaling, the polarization states are no longer stable, but exhibit multi-step degradation and cause reduced sense margin in distinguishable adjacent levels or even eventual memory window collapse; 2) the instability is caused by the temperature activated accumulation of switching probability under depolarization field stress, which could cause domain switching within the retention time at operating temperatures.  more » « less
Award ID(s):
1810005
NSF-PAR ID:
10243509
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
020 IEEE International Electron Devices Meeting (IEDM)
Page Range / eLocation ID:
4.5.1 to 4.5.4
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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