Understanding Nanoscale Plasticity by Quantitative In Situ Conductive Nanoindentation

Abstract

Electronic materials such as semiconductors, piezo‐ and ferroelectrics, and metal oxides are primary constituents in sensing, actuation, nanoelectronics, memory, and energy systems. Although significant progress is evident in understanding the mechanical and electrical properties independently using conventional techniques, simultaneous and quantitative electromechanical characterization at the nanoscale using in situ techniques is scarce. It is essential because coupling/linking electrical signal to the nanoscale plasticity provides vital information regarding the real‐time electromechanical behavior of materials, which is crucial for developing miniaturized smarter technologies. With the advent of conductive nanoindentation, researchers have been able to get valuable insights into the nanoscale plasticity (otherwise not possible by conventional means) in a wide variety of bulk and small‐volume materials, quantify the electromechanical properties, understand the dielectric breakdown phenomenon and the nature of electrical contacts in thin films, etc., by continuously monitoring the real‐time electrical signal changes during any point on the indentation load–hold–unload cycle. This comprehensive Review covers probing the electromechanical behavior of materials using in situ conductive nanoindentation, data analysis methods, the validity of the models and limitations, and electronic conduction mechanisms at the nanocontacts, quantification of resistive components, applications, progress, and existing issues, and provides a futuristic outlook.

Metrological Comparison of Available Methods to Correct Edge-Effect Local Plasticity in Instrumented Indentation Test

“…The frame compliance and the area shape function were calibrated per ISO 14577-2 method 4 in Annex D with certified reference material by NPL (SiO 2 and W) [31]. Ten replicated indentations were performed at (0.2, 0.3, 0.5, 0.7, 1, 1.5, 2, 3,4,5,6,7,8,9,10,12,15,17,20,23,25,30) N. All indentation cycles were force-controlled, with constant force gradient, and duration of the loading, holding and unloading phase of 30 s each. The investigated range is such to elicit ISE at low forces and a significant pile-up at high forces.…”

“…Last, the identification of discontinuities in the indentation curve is expedient to highlight phase changes and penetration of coating or oxide layers [ 13 ]. Data augmentation via electrical contact resistance (ECR) further enhances IIT, enabling the critical loads to induce phase change for semiconductors, e.g., silica, and germanium [ 14 , 15 ].…”

In situ and operando characterisation of Li metal – Solid electrolyte interfaces

“…Some also offer electrical measurement between the indentation tip and the sample. [49] With intelligent cell design, it seems possible to probe mechanical responses at the lithiumsolid electrolyte interface in situ akin to the work done on the lithium-silicon system by Epler and coworkers. [50] There are significant opportunities to pursue this approach, allowing the mechanical properties of chemical reaction products at the interface to be measured, as dynamic changes in stress/strain during cycling are quantified for a more comprehensive understanding of the chemo-mechanical degradation of these interfaces.…”

Anisotropic behavior of mechanical properties for the a- and c-domains in a (001) BaTiO3 single crystal

“…Moreover, current devices have been reduced to micro-scale, with components involving many domains, such that the mechanical properties of each ferroelectric domain play a critical role in the design, manufacture, and performance of devices. Therefore, the mechanical properties of the domains need further investigations for full understanding relevant to device performance [5,6].…”