Atomic-scale characterization of nitridation processes on Si(100)-2 x 1 surfaces by radical nitrogen

Citation
D. Matsushita et al., Atomic-scale characterization of nitridation processes on Si(100)-2 x 1 surfaces by radical nitrogen, JPN J A P 1, 40(4B), 2001, pp. 2827-2829
Citations number
11
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Volume
40
Issue
4B
Year of publication
2001
Pages
2827 - 2829
Database
ISI
SICI code
0021-4922(200104)40:4B<2827:ACONPO>2.0.ZU;2-X
Abstract
We have investigated the initial nitridation process of Si(100)-2 x I surfa ces by scanning tunneling microscopy (STM) and scanning tunneling spectrosc opy (STS). The nitridation was performed by radical nitrogen at a high temp erature of 850 degreesC. After the radical-nitrogen exposure of about I Lan gmuir, linear defects perpendicular to dimer rows were formed. Furthermore, doublet dark lines were frequently observed in the STM image. STS analysis of the dark-line regions clarified that the initial nitridation reaction o ccurs preferentially at the backbonds of surface Si atoms. Then, the nitrid ation proceeds via lateral growth of two-dimensional nitride-islands. These islands grow preferentially along the < 011 > direction perpendicular to t he Si dimer rows. STS spectra obtained from the 0.5-nm-thick nitride island s distinctly showed a bandgap of about 4.0 eV that is very close to the ban dgap of bulk Si3N4.