Charge retention characteristics of silicon nanocrystal layers by ultrahigh vacuum atomic force microscopy

Abstract

The nanoscale charge retention characteristics of both electrons and holes in SiO 2 layers containing silicon nanocrystals were investigated with ultrahigh vacuum conductive-tip noncontact atomic force microscopy. The results revealed much longer hole retention time ͑e.g., Ͼ1 day͒ than that of electrons ͑e.g., ϳ1 h͒. A three-dimensional electrostatic model was developed for charge quantification and analysis of charge dissipation. Based on the superior retention characteristics of holes, a p-channel nanocrystal memory working with holes is suggested to be an interesting choice in improving data retention or in further device scaling.