Optimization of metal-assisted chemical etching process in fabrication of p-type silicon wire arrays

The metal-assisted chemical etching (MCE) has attracted great attention because of the advantages such as simple and large area process, low-cost and compatible with existing semiconductor technology. We have achieved optimization conditions about two kinds of MCE method for fabrication of p-type silicon wire arrays. First one is one-step MCE that used AgNO₃ and BOE solution and second is two-step MCE in which silicon etching proceeds by BOE and H ₂O₂ solution after depositing Au by thermal evaporation. Particularly, the effect of etching parameters, such as etching time and AgNO₃ concentration in one-step MCE and metal catalyst thickness and etching solution temperature in two-step MCE on fabrication of silicon was investigated a morphology, length and etch rate of silicon wire. Finally, we have found important factors for fabrication of uniform and well aligned p-type silicon wire by MCE.