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Title: Resistance Drift in Melt-Quenched Ge 2 Sb 2 Te 5 Phase Change Memory Line Cells at Cryogenic Temperatures
We characterized resistance drift in phase change memory devices in the 80 K to 300 K temperature range by performing measurements on 20 nm thick, ∼70–100 nm wide lateral Ge2Sb2Te5(GST) line cells. The cells were amorphized using 1.5–2.5 V pulses with ∼50–100 ns duration leading to ∼0.4–1.1 mA peak reset currents resulting in amorphized lengths between ∼50 and 700 nm. Resistance drift coefficients in the amorphized cells are calculated using constant voltage measurements starting as fast as within a second after amorphization and for 1 h duration. Drift coefficients range between ∼0.02 and 0.1 with significant device-to-device variability and variations during the measurement period. At lower temperatures (higher resistance states) some devices show a complex dynamic behavior, with the resistance repeatedly increasing and decreasing significantly over periods in the order of seconds. These results point to charge trapping and de-trapping events as the cause of resistance drift.  more » « less
Award ID(s):
1710468
PAR ID:
10490627
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Institute of Physics
Date Published:
Journal Name:
ECS Journal of Solid State Science and Technology
Volume:
13
Issue:
2
ISSN:
2162-8769
Page Range / eLocation ID:
025001
Subject(s) / Keyword(s):
phase change memory resistance drift charge trapping
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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