VLS growth of doped Si-microprobe arrays using varying PH<inf>3</inf> flow with a fixed flow of Si<inf>2</inf>H<inf>6</inf> at low temperature

Abstract

Vapor-liquid-solid (VLS) growth, using Si2H6 as the gas source of Si, can be used to realize intrinsic Si microprobe arrays, which could be doped by diffusion process (at 1100degC) after VLS growth. But in this work we have demonstrated that by incorporating in-situ doping using the gas source of Si2H6 and PH3 with VLS growth process, doped n-Si microprobes can be realized directly at a temperature (around 700degC) lower than that required at diffusion process. Here we report the realization of n-Si microprobe arrays at low temperature by using Au-catalyzed selective VLS growth using varying flow of PH3 with a fixed flow of Si2H6. The effects of PH3 flow rates on the physical and electrical properties of these n-Si microprobes, under the condition of a fixed amount of Si2H6 flow, have been investigated in detail.