The primary challenge to exploit the nanowire as a truly one‐dimensional building block in nanoscale devices is the clear incorporation of scale effects into the operational performance. Size‐dependent behavior in physical properties of nanowires is the subject of intense experimental and computational studies for more than two decades. In this review, the measurement techniques and computational approaches to study scale effects on mechanical properties of nanowires are reviewed for fcc metallic, silicon, and zinc oxide structures. Advantages and disadvantages of each measurement tool are summarized with data reported in the literature. A similar comparison is carried out for computational techniques. Contradictions in the literature are highlighted with an assessment of research needs and opportunities, among which the plastic behavior of gold nanowires and elastic properties of silicon nanowires can be primarily mentioned. Furthermore, challenges associated with the coupling of measurement methods and modeling approaches are summarized. Finally, points of agreement between experimental measurements and computational studies are discussed paving the way for the utilization of nanowires in future nanoscale devices.

Si (100)Si ( 110) aSiO2 γr (J/m 2 ) 2.21 (2.15) 1.45 (1.73) 2.19 ± 0.2 d11(N/m) -8.77 +3.4 -22.1 ±1.3 d22(N/m) -8.77 -15.1 -22.1 ±1.3 f11(N/m) -0.88 -1.57 +1.11 ± 0.10 f22(N/m) -0.88 -0.95

This work proposes a new approach to characterize the mechanical properties of nanowires based on a combination of nanomechanical measurements and models. Silicon nanowires with a critical dimension of 90 nm and a length of 8 µm obtained through a monolithic process are characterized through insitu three-point bending tests. A nonlinear nanomechanical model is developed to

Understanding the origins of intrinsic stress in Si nanowires (NWs) is crucial for their successful utilization as transducer building blocks in next-generation, miniaturized sensors based on nanoelectromechanical systems (NEMS). With their small size leading to ultrahigh-resonance frequencies and extreme surface-to-volume ratios, silicon NWs raise new opportunities regarding sensitivity, precision, and speed in both physical and biochemical sensing. With silicon optoelectromechanical properties strongly dependent on the level of NW intrinsic stress, various studies have been devoted to the measurement of such stresses generated, for example, as a result of harsh fabrication processes. However, due to enormous NW surface area, even the native oxide that is conventionally considered as a benign surface condition can cause significant stresses. To address this issue, a combination of nanomechanical characterization and atomistic simulation approaches is developed. Relying only on low-temperature processes, the fabrication approach yields monolithic NWs with optimum boundary conditions, where NWs and support architecture are etched within the same silicon crystal. Resulting NWs are characterized by transmission electron microscopy and micro-Raman spectroscopy. The interpretation of results is carried out through molecular dynamics simulations with ReaxFF potential facilitating the incorporation of humidity and temperature, thereby providing a close replica of the actual oxidation environmentin contrast to previous dry oxidation or self-limiting thermal oxidation studies. As a result, consensus on significant intrinsic tensile stresses on the order of 100 MPa to 1 GPa was achieved as a function of NW critical dimension and aspect ratio. The understanding developed herein regarding the role of native oxide played in the generation of NW intrinsic stresses is important for the design and development of silicon-based NEMS.

With the aim of contributing to the fight against the coronavirus disease 2019 (COVID-19), numerous strategies have been proposed. While developing an effective vaccine can take months up to years, detection of infected patients seems like one of the best ideas for controlling the situation. The role of biosensors in containing highly pathogenic viruses, saving lives and economy is evident. A new competitive numerical platform specifically for designing microfluidic-integrated biosensors is developed and presented in this work. Properties of the biosensor, sample, buffer fluid and even the microfluidic channel can be modified in this model. This feature provides the scientific community with the ability to design a specific biosensor for requested point-of-care (POC) applications. First, the validation of the presented numerical platform against experimental data and then results and discussion, highlighting the important role of the design parameters on the performance of the biosensor is presented. For the latter, the baseline case has been set on the previous studies on the biosensors suitable for SARS-CoV, which has the highest similarity to the 2019 nCoV. Subsequently, the effects of concentration of the targeted molecules in the sample, installation position and properties of the biosensor on its performance were investigated in 11 case studies. The presented numerical framework provides an insight into understanding of the virus reaction in the design process of the biosensor and enhances our preparation for any future outbreaks. Furthermore, the integration of biosensors with different devices for accelerating the process of defeating the pandemic is proposed.

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