Triangular Si3N4 Nano-scale Pits On The Stepped Si (553) Surface By Ion Induced Reaction   

¹Physics of Energy Harvesting, National Physical Laboratory (CSIR-NPL), Dr. K.S. Krishnan Road, New Delhi 110012, India

²Department of Physics, Jamia Millia  Islamia, New Delhi 110025, India

Adv. Mater. Lett., 2015, 6 (11), pp 941-946

DOI: 10.5185/amlett.2015.5894

Publication Date (Web): Oct 26, 2015

Copyright © IAAM-VBRI Press

E-mail: govind@nplindia.org

Abstract

Triangular nano-scale pits (TNPs) of Si₃N₄ are fabricated by reactive nitrogen ion sputtering using low energy nitrogen ions on the Si (553) surface at 500 °C. The electronic structure of the developing Si₃N₄ interface was monitored in-situ by Auger Electron Spectroscopy (AES) while the ion beam induced surface reaction was analysed via X-Ray and Ultraviolet photoemission spectroscopy (XPS & UPS), Photoluminescence and Raman spectroscopy. The morphological development of nanoscale pit structures was observed by Scanning Electron Microscopy (SEM). The formation of Si₃N₄ was identified by AES, with the appearance of the characteristic reacted Si(LVV) peak at 83 eV, while photoemission spectroscopy confirmed the stoichiometry of Si₃N₄. The valence band maximum was observed to be located at 2.4 eV below the Fermi level.  SEM images showed uniformly distributed Si₃N₄ TNPs with size varying between 250 to 600 nm (length) and 200 to 400 nm (width). Our work underlines the influence of ion energy and substrate temperature and establishes the conditions for the growth of Si₃N₃ TNPs by ion induced reactive sputtering.

Keywords

Triangular nanostructures, Si₃N_4, AES, XPS, SEM.