Boron Doping of Tin-Catalyzed VLS Grown Silicon Nanowires on Cu Substrate Using Hot Wire Assisted Chemical Vapor Deposition

In this study, we concentrate on the growth of tin (Sn)-catalyzed boron-doped silicon nanowires (SiNWs) on copper (Cu) substrates via hot wire-assisted chemical vapor deposition (HWCVD). In order to improve the efficiency of batteries and thermoelectric devices, doped SiNWs grown directly on Cu can prove to be very helpful because of the high conductivity of Cu substrate. Utilizing silane (SiH
4
) and diborane (B
2
H
6
) during the formation of SiNWs allows for the boron doping of these nanowires. From SEM, the boron-doped SiNWs are observed at a low B
2
H
6
to SiH
4
flow ratio (0.1 to 0.4) and the SiNWs do not grow at a high B
2
H
6
to SiH
4
flow ratio of 0.5 for Sn catalyst of 55 nm diameter. The core-shell structure of boron-doped SiNWs have been observed by TEM. Additionally, it has been noted that the density of doped SiNWs decreases by increasing Sn catalyst size to 55 nm at B
2
H
6
to SiH
4
flow ratio ≥ 0.5. Here, the focus is on altering the doping concentration and template size to control the doping and density of SiNWs on the Cu substrate.