Gold Nanoparticles Assisted Silicon Nanowire Growth using Vapor Liquid Solid Method

Silicon Nanowires (SiNWs) are promising 1D semiconductor nanostructures which are intensively researched in many countries due to its potential applications in various fields such as MOSFET channel, and/or wiring, solar cells, chemical and biological sensors. We used gold nanoparticles (AuNPs) which has low eutectic temperature, such as a metal catalyst in Vapor Liquid Solid (VLS) method to grow SiNW on top of Silicon < 100 > substrates. AuNPs are synthesized using Turkevich method and then deposited on the Silicon substrate using dip coating method. To grow SiNWs, we placed the sample inside a Low Pressure Chemical Vapor Deposition (LPCVD) reactor with temperature around the Si-Au eutectic temperature (similar to 500 degrees C), after the temperature is stable we flowed Silane (SiH4) gas diluted in Nitrogen gas to the chamber for several minutes. We found that the SiNWs are grown with AuNPs as the nanowire cap on the top of it. SiNWs have an average length around 500-800 nm with diameter proportional to its gold catalyst. By optimizing the growth parameter, we aim to achieve vertical SiNWs that can be used for practical devices such as chemical sensors.