In situ thermal behavior of resistance drift in GeTe and Ge2Sb2Te5nanowires via Raman thermometry

Sungjin Park; Taeok Kim; Soobin Hwang; Dambi Park; Min Ahn; Mann Ho Cho

doi:10.1039/d0tc00781a

In situ thermal behavior of resistance drift in GeTe and Ge₂Sb₂Te₅nanowires via Raman thermometry

Sungjin Park, Taeok Kim, Soobin Hwang, Dambi Park, Min Ahn, Mann Ho Cho

Department of Physics

Research output: Contribution to journal › Article › peer-review

Abstract

Time-dependent resistance drift in chalcogenide phase change materials is known to cause instabilities in phase-change random access memories (PRAMs). In this study, the resistance drift of the RESET state of GeTe and Ge2Sb2Te5 (GST) nanowires during memory switching was investigated using an optical method to determine the relationship between variation in resistance and time-dependent thermal properties. Changes in morphology and crystal structure were caused by the formation of voids and hillocks in nanowires in the RESET state, which affected the phonon scattering in GeTe and GST nanowires. Consequently, the thermal conduction of the GeTe and GST nanowires in the RESET state was observed to be significantly lower than that in the initial single-crystalline state. Further, it was observed that as the annealing duration of the retention test was increased, the resistance decreased and thermal conduction increased, even though the morphologies of the nanowires were restored to the initial state. These changes were induced by thermally assisted atomic migration, indicating the occurrence of a local structural phase transition in the GeTe and GST nanowires via the formation of voids and hillocks. Our results explain the cause behind the resistance drift observed in GeTe and GST nanowires in the RESET state with bi-polar memory switching characteristics.

Original language	English
Pages (from-to)	11032-11041
Number of pages	10
Journal	Journal of Materials Chemistry C
Volume	8
Issue number	32
DOIs	https://doi.org/10.1039/d0tc00781a
Publication status	Published - 2020 Aug 28

Bibliographical note

Funding Information:
This work was supported by the Ministry of Trade, Industry & Energy (MOTIE) in Korea (Project No. 10080625) and the Korea Semiconductor Research Consortium (KSRC) through a project for developing source technologies for future semiconductor devices, and was financially supported by a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (Grant No. 2018R1A2A1A05023214).

Publisher Copyright:
© The Royal Society of Chemistry.

All Science Journal Classification (ASJC) codes

Chemistry(all)
Materials Chemistry

Access to Document

10.1039/d0tc00781a

Cite this

@article{e7453ff1417643cc93bde52ff2e2c2b6,

title = "In situ thermal behavior of resistance drift in GeTe and Ge2Sb2Te5nanowires via Raman thermometry",

abstract = "Time-dependent resistance drift in chalcogenide phase change materials is known to cause instabilities in phase-change random access memories (PRAMs). In this study, the resistance drift of the RESET state of GeTe and Ge2Sb2Te5 (GST) nanowires during memory switching was investigated using an optical method to determine the relationship between variation in resistance and time-dependent thermal properties. Changes in morphology and crystal structure were caused by the formation of voids and hillocks in nanowires in the RESET state, which affected the phonon scattering in GeTe and GST nanowires. Consequently, the thermal conduction of the GeTe and GST nanowires in the RESET state was observed to be significantly lower than that in the initial single-crystalline state. Further, it was observed that as the annealing duration of the retention test was increased, the resistance decreased and thermal conduction increased, even though the morphologies of the nanowires were restored to the initial state. These changes were induced by thermally assisted atomic migration, indicating the occurrence of a local structural phase transition in the GeTe and GST nanowires via the formation of voids and hillocks. Our results explain the cause behind the resistance drift observed in GeTe and GST nanowires in the RESET state with bi-polar memory switching characteristics.",

author = "Sungjin Park and Taeok Kim and Soobin Hwang and Dambi Park and Min Ahn and Cho, {Mann Ho}",

note = "Funding Information: This work was supported by the Ministry of Trade, Industry & Energy (MOTIE) in Korea (Project No. 10080625) and the Korea Semiconductor Research Consortium (KSRC) through a project for developing source technologies for future semiconductor devices, and was financially supported by a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (Grant No. 2018R1A2A1A05023214). Publisher Copyright: {\textcopyright} The Royal Society of Chemistry.",

year = "2020",

month = aug,

day = "28",

doi = "10.1039/d0tc00781a",

language = "English",

volume = "8",

pages = "11032--11041",

journal = "Journal of Materials Chemistry C",

issn = "2050-7526",

publisher = "Royal Society of Chemistry",

number = "32",

}

TY - JOUR

T1 - In situ thermal behavior of resistance drift in GeTe and Ge2Sb2Te5nanowires via Raman thermometry

AU - Park, Sungjin

AU - Kim, Taeok

AU - Hwang, Soobin

AU - Park, Dambi

AU - Ahn, Min

AU - Cho, Mann Ho

N1 - Funding Information: This work was supported by the Ministry of Trade, Industry & Energy (MOTIE) in Korea (Project No. 10080625) and the Korea Semiconductor Research Consortium (KSRC) through a project for developing source technologies for future semiconductor devices, and was financially supported by a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (Grant No. 2018R1A2A1A05023214). Publisher Copyright: © The Royal Society of Chemistry.

PY - 2020/8/28

Y1 - 2020/8/28

N2 - Time-dependent resistance drift in chalcogenide phase change materials is known to cause instabilities in phase-change random access memories (PRAMs). In this study, the resistance drift of the RESET state of GeTe and Ge2Sb2Te5 (GST) nanowires during memory switching was investigated using an optical method to determine the relationship between variation in resistance and time-dependent thermal properties. Changes in morphology and crystal structure were caused by the formation of voids and hillocks in nanowires in the RESET state, which affected the phonon scattering in GeTe and GST nanowires. Consequently, the thermal conduction of the GeTe and GST nanowires in the RESET state was observed to be significantly lower than that in the initial single-crystalline state. Further, it was observed that as the annealing duration of the retention test was increased, the resistance decreased and thermal conduction increased, even though the morphologies of the nanowires were restored to the initial state. These changes were induced by thermally assisted atomic migration, indicating the occurrence of a local structural phase transition in the GeTe and GST nanowires via the formation of voids and hillocks. Our results explain the cause behind the resistance drift observed in GeTe and GST nanowires in the RESET state with bi-polar memory switching characteristics.

AB - Time-dependent resistance drift in chalcogenide phase change materials is known to cause instabilities in phase-change random access memories (PRAMs). In this study, the resistance drift of the RESET state of GeTe and Ge2Sb2Te5 (GST) nanowires during memory switching was investigated using an optical method to determine the relationship between variation in resistance and time-dependent thermal properties. Changes in morphology and crystal structure were caused by the formation of voids and hillocks in nanowires in the RESET state, which affected the phonon scattering in GeTe and GST nanowires. Consequently, the thermal conduction of the GeTe and GST nanowires in the RESET state was observed to be significantly lower than that in the initial single-crystalline state. Further, it was observed that as the annealing duration of the retention test was increased, the resistance decreased and thermal conduction increased, even though the morphologies of the nanowires were restored to the initial state. These changes were induced by thermally assisted atomic migration, indicating the occurrence of a local structural phase transition in the GeTe and GST nanowires via the formation of voids and hillocks. Our results explain the cause behind the resistance drift observed in GeTe and GST nanowires in the RESET state with bi-polar memory switching characteristics.

UR - http://www.scopus.com/inward/record.url?scp=85092567311&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85092567311&partnerID=8YFLogxK

U2 - 10.1039/d0tc00781a

DO - 10.1039/d0tc00781a

M3 - Article

AN - SCOPUS:85092567311

SN - 2050-7526

VL - 8

SP - 11032

EP - 11041

JO - Journal of Materials Chemistry C

JF - Journal of Materials Chemistry C

IS - 32

ER -