Automated measurement method for assessing thermal-dependent electronic characteristics of thin boron-doped diamond-graphene nanowall structures

Abstract

This paper investigates the electrical properties of boron-doped diamond-graphene (B:DG) nanostructures, focusing on their semiconductor characteristics. These nanostructures are synthesized on fused silica glass and Si wafer substrates to compare their behaviour on different surfaces. A specialized measurement system, incorporating Python-automated code, was developed for an in-depth analysis of electronic properties under various contact configurations. This approach allowed for a detailed exploration of charge transport mechanisms within the nanostructures. The research highlights a decrease in resistivity with increased deposition time, as shown by Arrhenius plot analysis. This trend is linked to the formation and evolution of multi-wall graphene structures. SEM images showed nanowall structures formed more readily on amorphous fused silica substrates, enabling unrestricted growth. TOF-SIMS analysis revealed uneven boron atom distribution through the film depth. A significant finding is a reduction in conductive activation energy in samples grown in microwave plasma from 197 meV to 87 meV as deposition time increased from 5 to 25 min. Furthermore, the study identifies a shift in transport mechanisms from variable range hopping (VRH) below 170 K to thermally activated (TA) conduction above 200 K. These insights advance our understanding of the electronic behaviours in B:DG nanostructures and underscore their potential in electronic device engineering, opening new paths for future research and technological developments.