Physical and chemical properties of SiSiO 2 transition regions

Abstract

Current understanding on physical and chemical properties of Si-SiO 2 transition regions is reviewed from the viewpoints of the morphology and the chemical structure of the transition region and the interface trap states. Normal and cross-sectional transmission microscopies have revealed the interface asperity which is consistent with the study of the carrier mobility in surface layers. Various analytical measurements, such as ion-scattering spectrometry and electron spectroscopy, have indicated an abrupt transition model for the SiSiO 2 systems. The transition region includes strained SiO 2, monolayer of SiO x as a connective region from the bulk SiO 2 to Si and disordered Si layers in the Si substrate. The abrupt transition model has been used for theoretical calculation of the interface trap states originated by bonding defects, and also does not conflict with the continuous random network model for the SiSiO 2 transition region.