Direct Patterning of Boron-doped Amorphous Carbon Using Focused Ion Beam-assisted Chemical Vapor Deposition

TL;DR

This paper demonstrates a method for directly patterning boron-doped amorphous carbon films using focused ion beam-assisted chemical vapor deposition, revealing their semiconducting properties and pressure-dependent electrical behavior.

Contribution

It introduces a novel focused ion beam-assisted CVD technique for patterning boron-doped amorphous carbon with detailed analysis of its electrical and structural properties.

Findings

Boron was successfully incorporated into amorphous carbon films.

The films exhibited semiconducting behavior with a band gap of 285 meV.

Applying pressure significantly reduced the film's electrical resistance.

Abstract

The deposition of boron-doped amorphous carbon thin films on SiO2 substrate was achieved via a focused ion beam-assisted chemical vapor deposition of triphenyl borane (C18H15B) and triphenyl borate (C18H15BO3). The existence of boron in the deposited film from triphenyl borane, with a precursor temperature of 90 {\deg}C, was confirmed by a core level X-ray photoelectron spectroscopy analysis. The film exhibited a semiconducting behavior with a band gap of 285 meV. Although the band gap was decreased to 197 meV after an annealing process, the film was still semiconductor. Additionally, a drastic reduction of the resistance on the deposited film by applying pressures was observed from an in-situ electrical transport measurements using a diamond anvil cell.