Reduction of •SiSi3 defect density at the Si/SiO2 interface by sol-gel SiO2 thin film passivation

The effect of SiO2 thin film passivation by sol-gel processeswith various acid catalysts, ethanol (EtOH): tetraethyl orthosilicate (TEOS) volume ratios and baking temperatures on the carrier lifetime of the Si surface and Si/SiO2 interface propertieswas studied. SiO2 thin film passivation prepared by H2SO4 catalystwith a EtOH: TEOS volume ratio of 10: 1 at a baking temperature of 50 degrees C greatly increased the carrier lifetime on the various Si wafers regardless of dopant type, wafer resistivity and crystal orientation. For example, the carrier lifetime increased from 28 to 316 mu s before and after the sol-gel SiO2 passivation on the Si (100) surface with resistivity higher than 1000 Omega cm. It was confirmed that the increase of carrier lifetime resulted from the significant decrease in the defect density related to the center dot Si Si-3 dangling bond at the Si/SiO2 interface. In the current study, proper solgel SiO2 film passivation increased the carrier lifetime on the Si surface by controlling the formation of center dot Si Si-3 defects at the Si/SiO2 interface. (C) 2017 Elsevier B.V. All rights reserved.