After immersion in hydrofluoric acid,the sheet resistance of a 220-nm-thick silicon nanomembrane,measured in dry air by van der Pauw method,drops around two orders of magnitude initially,then increases and reaches the...After immersion in hydrofluoric acid,the sheet resistance of a 220-nm-thick silicon nanomembrane,measured in dry air by van der Pauw method,drops around two orders of magnitude initially,then increases and reaches the level of a sample with a native oxide surface in about one month.The surface component and oxidation rate are also characterized by x-ray photo electronic spectroscopy measurement.Fluorine is found to play a significant role in improving conductivity and has no apparent influence on the oxidation rate after hydrofluoric acid treatment.展开更多
基金by the National Basic Research Program of China under Grant No 2011CB301900the National Natural Science Foundation of China under Grant Nos 60990311,60820106003 and 60906025+1 种基金the Natural Science Foundation of Jiangsu Province(BK2008019)China Scholarship Council(CSC).
文摘After immersion in hydrofluoric acid,the sheet resistance of a 220-nm-thick silicon nanomembrane,measured in dry air by van der Pauw method,drops around two orders of magnitude initially,then increases and reaches the level of a sample with a native oxide surface in about one month.The surface component and oxidation rate are also characterized by x-ray photo electronic spectroscopy measurement.Fluorine is found to play a significant role in improving conductivity and has no apparent influence on the oxidation rate after hydrofluoric acid treatment.