Atomic Layer Deposition of Sb2 Te3 /GeTe Superlattice Film and Its Melt-Quenching-Free Phase-Transition Mechanism for Phase-Change Memory

Chanyoung Yoo; Jeong Woo Jeon; Seungjae Yoon; Yan Cheng; Gyuseung Han; Wonho Choi; Byongwoo Park; Gwangsik Jeon; Sangmin Jeon; Woohyun Kim; Yonghui Zheng; Jongho Lee; Junku Ahn; Sunglae Cho; Scott B Clendenning; Ilya V Karpov; Yoon Kyung Lee; Jung-Hae Choi; Cheol Seong Hwang

doi:10.1002/adma.202207143

Atomic Layer Deposition of Sb₂ Te₃ /GeTe Superlattice Film and Its Melt-Quenching-Free Phase-Transition Mechanism for Phase-Change Memory

Adv Mater. 2022 Dec;34(50):e2207143. doi: 10.1002/adma.202207143. Epub 2022 Nov 3.

Authors

Chanyoung Yoo¹, Jeong Woo Jeon¹, Seungjae Yoon^{1

2}, Yan Cheng³, Gyuseung Han^{1

2}, Wonho Choi¹, Byongwoo Park¹, Gwangsik Jeon¹, Sangmin Jeon¹, Woohyun Kim¹, Yonghui Zheng³, Jongho Lee⁴, Junku Ahn⁴, Sunglae Cho⁴, Scott B Clendenning⁵, Ilya V Karpov⁵, Yoon Kyung Lee⁶, Jung-Hae Choi², Cheol Seong Hwang¹

Affiliations

¹ Department of Materials Science and Engineering, and Inter-University Semiconductor Research Center, Seoul National University, Seoul, 08826, Republic of Korea.
² Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea.
³ Key Laboratory of Polar Materials and Devices, Department of Electronics, East China Normal University, Shanghai, 200241, China.
⁴ SK Hynix Inc., Icheon, Gyeonggi, 17336, Republic of Korea.
⁵ Components Research, Intel Corporation, Hillsboro, OR, 97124, USA.
⁶ Division of Advanced Materials Engineering, Jeonbuk National University, Jeonju, Jeonbuk, 54896, Republic of Korea.

PMID: 36271720
DOI: 10.1002/adma.202207143

Abstract

Atomic layer deposition (ALD) of Sb₂ Te₃ /GeTe superlattice (SL) film on planar and vertical sidewall areas containing TiN metal and SiO₂ insulator is demonstrated. The peculiar chemical affinity of the ALD precursor to the substrate surface and the 2D nature of the Sb₂ Te₃ enable the growth of an in situ crystallized SL film with a preferred orientation. The SL film shows a reduced reset current of ≈1/7 of the randomly oriented Ge₂ Sb₂ Te₅ alloy. The reset switching is induced by the transition from the SL to the (111)-oriented face-centered-cubic (FCC) Ge₂ Sb₂ Te₅ alloy and subsequent melt-quenching-free amorphization. The in-plane compressive stress, induced by the SL-to-FCC structural transition, enhances the electromigration of Ge along the [111] direction of FCC structure, which enables such a significant improvement. Set operation switches the amorphous to the (111)-oriented FCC structure.

Keywords: Sb 2Te 3/GeTe superlattice; atomic layer deposition; oriented growth; phase-change memory; switching current density; switching mechanisms; vertical devices.

Abstract

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