An SEM-Based Nanomanipulation System for Multiphysical Characterization of Single InGaN/GaN Nanowires

Abstract

Nanomaterials possess superior mechanical, electrical, and optical properties suitable for device applications in different fields such as nanoelectronics, photonics, and sensors. Characterizing the multiphysical properties of single nanomaterials and nanostructures provides experimental guidelines for synthesis and device applications of functional nanomaterials. Nanomanipulation techniques under scanning electron microscopy (SEM) have enabled the testing of mechanical and electrical properties of various nanomaterials. However, the introduction of micro-photoluminescence ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula> -PL) measurement into an SEM setup for in-situ single nanomaterial characterization is still experimentally challenging; in particular, the seamless integration of the mechanical, electrical, and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula> -PL testing techniques inside an SEM for multi-field-coupled characterization of single nanostructures is still unexplored. In this work, we report the first SEM-based nanomanipulation system for multiphysical characterization of single nanomaterials. A custom-made, optical-microfiber-based <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula> -PL setup is integrated onto a nanomanipulation system with four nanomanipulators inside an SEM. The system is also equipped with a conductive nanoprobe and a conductive atomic force microscopy (AFM) probe for electrical nanoprobing and electroluminescence (EL) measurement of single nanomaterials with contact force feedback. Using the system, field-coupled characterization (i.e., optomechanical, optoelectronic, electromechanical, and mechano-optoelectronic testing) of single InGaN/GaN nanowires (NWs) are conducted; and, for the first time, the effect of mechanical compression applied to individual InGaN/GaN NWs on its optoelectronic property is revealed. Note to Practitioners—With the rapid advances of nanophotonics and nanoelectronics, the optical and optoelectronic characterization of semiconductive nanomaterials becomes widely used for guiding the material synthesis and improving the nanodevice performance. However, few studies on optical-relevant characterization were carried out in SEM, mainly due to the limited space of an SEM chamber, making it challenging to integrate optical components for effective optical excitation and luminescence measurement. To address this issue, space-saving optical microfibers were integrated into the SEM chamber for in-situ optoelectronic characterization of semiconductor NWs, along with the seamless integration of mechanical and electrical nanoprobing tools for electromechanical characterization. The developed nanomanipulation system will greatly facilitate the multiphysical testing of semiconductor nanomaterials, and thus expedite their synthesis optimization processes and broaden their optoelectronic device applications.