Structural evolution of low-dimensional metal oxide semiconductors under external stress

Abstract

Metal oxide semiconductors (MOSs) are attractive candidates as functional parts and connections in nanodevices. Upon spatial dimensionality reduction, the ubiquitous strain encountered in physical reality may result in structural instability and thus degrade the performance of MOS. Hence, the basic insight into the structural evolutions of low-dimensional MOS is a prerequisite for extensive applications, which unfortunately remains largely unexplored. Herein, we review the recent progress regarding the mechanical deformation mechanisms in MOSs, such as CuO and ZnO nanowires (NWs). We report the phase transformation of CuO NWs resulting from oxygen vacancy migration under compressive stress and the tensile strain-induced phase transition in ZnO NWs. Moreover, the influence of electron beam irradiation on interpreting the mechanical behaviors is discussed.

Size-Dependent Phase Transition in Ultrathin Ga2O3 Nanowires

“…The exponential development of economy and technology has driven the accelerated downscaling of metal-oxide-semiconductor (MOS) based field-effect transistors and photocatalysts. − In this sense, the diverse structural polymorphs in MOSs have been considered a double-edged sword because: (1) they have raised serious design issues due to material limitations within the nanometer range, − where the properties and structures are greatly affected by their size and surface characteristics, − and (2) on the other hand, they offer an unparalleled chance to finely tune the physical and chemical properties via phase engineering. − For example, due to the inevitable heat generated when more and more circuits are packed into the small area, polymorphic phase transitions caused by rising temperature or mechanical stress induced by thermal expansion can severely degrade device performance. , Hence, clarifying the possible influence of the size/surface on microstructures is a prerequisite to realizing property-oriented device design.…”

“…12−15 For example, due to the inevitable heat generated when more and more circuits are packed into the small area, 5 polymorphic phase transitions caused by rising temperature or mechanical stress induced by thermal expansion can severely degrade device performance. 4,9 Hence, clarifying the possible influence of the size/surface on microstructures is a prerequisite to realizing property-oriented device design.…”

Preface to the Special Topic on In-Situ and in-operando Characterization of Semiconductor Materials and Devices

“…Fang et al summarize the recent progress of in-situ characterization techniques on exploring the dynamic behavior of catalyst materials and reaction intermediates [4] . Semiconductor photocatalytic processes revealed by microscopic imaging and spectroscopic characterization are discussed.…”