Indexed by: Journal paper

First Author: TONG HAO

Correspondence Author: 缪向水

Co-author: 缪向水,程晓敏,yangzhe,余念念

Journal: JOURNAL OF APPLIED PHYSICS

Affiliation of Author(s): 华中科技大学

Discipline: Engineering

First-Level Discipline: Electronic Science And Technology

Document Type: J

Volume: 118

Issue: 7

Page Number: 075704

Key Words: PHASE-CHANGE MATERIALSP-TYPECHALCOGENIDESTRANSITIONCONDUCTIONMEMORYSYSTEM

DOI number: 10.1063/1.4928630

Date of Publication: 4223-07-01

Abstract: Opposite to the almost persistent p-type conductivity of the crystalline chalcogenides along the GeTe-Sb2Te3 tie line, n-type Hall mobility is observed in crystalline GeTe/Sb2Te3 superlattice-like material (SLL) with a short period length. We suggest that this unusual carrier characteristic originates from the structural disorder introduced by the lattice strain and dangling bonds at the SLL interfaces, which makes the crystalline SLLs behave like the amorphous chalcogenides. Detailed structural disorder in crystalline SLL has been studied by Raman scattering, X-ray photoelectron spectroscopy, as well as Variable-energy positron annihilation spectroscopy measurements. First-principles calculations results show that this structural disorder gives rise to three-site junctions that dominate the charge transport as the period length decreases and result in the anomalously signed Hall effect in the crystalline SLL. Our findings indicate a similar tetrahedral structure in the amorphous and crystalline states of SLLs, which can significantly reduce the entropy difference. Due to the reduced entropy loss and increased resistivity of crystalline phase introduced by disorder, it is not surprising that the SLLs exhibit extremely lower RESET current and power consumption. (C) 2015 AIP Publishing LLC.

Links to published journals: https://www.osti.gov/biblio/22494776#:~:text=First-principles%20calculations%20results%20show%20that%20this%20structural%20disorder,anomalously%20signed%20Hall%20effect%20in%20the%20crystalline%20SLL.