Selectively formation of porous silicon array using highly resistive silicon layer as masking materials

A new technology using ion implantation technique to create the selectively patterned porous silicon structures is presented in this paper. Hydrogen ions were first selectively implanted into silicon substrates and resulted in a highly resistive silicon layer. This layer can be used as a mask to selectively etch the un-implanted areas by electrochemical etching of crystalline silicon in HF-based solutions and lead to the formation of PS arrays. The quality of resulted PS were characterized by the analysis tools like SEM, AFM, etc. It is concluded that the ion implanted silicon can be used as the mask material for the selectively formation of PS patterns. The masking capability of the implanted Si layer is dependent upon the implantation conditions. The relationship between the masking capability of highly resistive silicon layer and the implantation condition (parameters like dose, time) were discussed. The developed technique is quite simple and can be used to form the fine PS patterns.