Silicon nitride is a widely used material in electronics, although generally in its amorphous or polycrystalline phase. However, silicon nitride shows also the remarkable property to grow epitaxially on Si(111), owing to a negligible lattice mismatch (<1.2% between 1x1 cell of the ?-Si3N4 (0001) and the 2x2 cell of the Si(111)). Moreover, once the thermal nitridation is performed, the surface of the nitride shows a 8x8 reconstruction. Although much effort has been devoted to the study of this interface, a full understanding of the 8x8 surface reconstruction and of the chemical bonds at the interface has not been achieved so far. This is of paramount importance as the presence of surface and interface dangling bonds (DBs) may induces gap states, creating tunnelling channels which can reduce the performance of electronic devices. After a brief review of the recent results reached in PES (PhotoElectron Spectroscopy), LEED (Low Energy Electron Diffraction), STM (Scanning Tunneling Microscopy) and DFT (Density Functional Theory), we will concentrate on the electronic structure of the system by showing our recent ARPES (Angle Resolved PhotoElectron Spectroscopy) measurements. R. Flammini et al. Phys. Rev. B 91, 075303 (2015)
On the surface resonance of the 8x8-reconstructed beta-Si3N4(0001)/Si(111)
R Flammini
2015
Abstract
Silicon nitride is a widely used material in electronics, although generally in its amorphous or polycrystalline phase. However, silicon nitride shows also the remarkable property to grow epitaxially on Si(111), owing to a negligible lattice mismatch (<1.2% between 1x1 cell of the ?-Si3N4 (0001) and the 2x2 cell of the Si(111)). Moreover, once the thermal nitridation is performed, the surface of the nitride shows a 8x8 reconstruction. Although much effort has been devoted to the study of this interface, a full understanding of the 8x8 surface reconstruction and of the chemical bonds at the interface has not been achieved so far. This is of paramount importance as the presence of surface and interface dangling bonds (DBs) may induces gap states, creating tunnelling channels which can reduce the performance of electronic devices. After a brief review of the recent results reached in PES (PhotoElectron Spectroscopy), LEED (Low Energy Electron Diffraction), STM (Scanning Tunneling Microscopy) and DFT (Density Functional Theory), we will concentrate on the electronic structure of the system by showing our recent ARPES (Angle Resolved PhotoElectron Spectroscopy) measurements. R. Flammini et al. Phys. Rev. B 91, 075303 (2015)I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
