论文类型：期刊论文
第一作者：王校杰
通讯作者：童浩
合写作者：缪向水,钱航,周凌珺
发表刊物：Applied Physics Letters
所属单位：华中科技大学
学科门类：工学
一级学科：电子科学与技术
文献类型：J
卷号：113
期号：23
页面范围：232903
关键字：First-principle calculations, Phase transitions, Ferroelectric devices, Ferroelectric materials, Raman spectroscopy, Semiconductor materials, Thin films, Chalcogenides, Depolarization
DOI码：10.1063/1.5049888
发表时间：4343-12-01
摘要：A stable ferroelectric phase or Curie temperature (Tc) above room temperature is essential forferroelectric devices. However, the fast Tcdrop of ferroelectric thin films has become a vital factorinhibiting the scaling down of ferroelectric devices. Many efforts have been made to slow downthe Tcdrop in conventional insulating ferroelectric thin films, but they are costly and complex. Asemiconducting ferroelectric, GeTe, is proposed in this letter, which shows an abnormal stability ofthe ferroelectric phase as the film thickness decreases to as thin as 3 nm. The ferroelectric Curietemperatures of GeTe thin films with different thicknesses have been studied using variable-temperature Raman measurements. The self-screening process of free carriers provided by intrinsicGe vacancies in GeTe films plays an important role in cancelling the depolarization field accordingto first principles calculations and results in an abnormal stability of ferroelectricity in ultrathinGeTe films. Self-screening by free carriers in GeTe unravels that the ferroelectric phase couldremain stable in low dimension semiconducting ferroelectrics. These results provide a straightfor-ward solution for high density ferroelectric devices and show promising application of semiconducting ferroelectrics in large current ferroelectric diodes.
发布期刊链接：https://pubs.aip.org/aip/apl/article/113/23/232903/36366/Self-screening-induced-abnormal-stability-of