PHOTOLUMINESCENCE CONTROL OF COLLOIDAL SILICON NANOCRYSTALS BY CHEMICAL ETCHING OF RAW POROUS SILICON POWDER

We demonstrated light emission color control of colloidal silicon nanocrystals by chemical etching of porous silicon (PSi) flakes. The colloidal silicon nanocrystals derived from post-etched PSi flakes in hydrofluoric acid (HF) and ethanol show different light emission color due to reduction of silicon core size. The colors are changed from red to yellow depending on the etching conditions such as time and composition of etching