Elsevier

Vacuum

Volume 51, Issue 4, 1 December 1998, Pages 673-676
Vacuum

Physical properties of reactive sputtered tin-nitride thin films

https://doi.org/10.1016/S0042-207X(98)00271-1Get rights and content

Abstract

We report on the physical properties of tin-nitride thin films deposited onto glass substrates by rf reactive sputtering. The crystal structure of the tin-nitride films is hexagonal and the lattice parameters are calculated from X-ray diffraction patterns as a=0.369 nm and c=0.529 nm. X-ray photoelectron spectroscopy reveals the bonding states of the polycrystalline tin-nitride films. Photoelectron lines and Auger lines are discussed in detail.

Introduction

Tin nitride (SnNx) is one of the group IV nitrides and has not been extensively studied. We found the electrochromic behavior of amorphous tin-nitride films prepared by ion plating, and investigated the fundamental characteristics of electrochromic cells based on this material.[1]The chemical bonding states of both amorphous and polycrystalline tin-nitride films prepared by ion plating and reactive sputtering were investigated using X-ray photoelectron spectroscopy (XPS).2, 3Recently, further studies have been performed on the synthesis of polycrystalline tin-nitride films by reactive sputtering.4, 5Lima et al. investigated the crystal structure and chemical composition of polycrystalline tin-nitride films prepared by reactive magnetron sputtering.[4]They found that the films had a C6 hexagonal structure isomorphous to Ca(OH)2 and had a tin-rich composition. Maruyama et al. studied the dependence of various physical properties of polycrystalline tin-nitride films on sputtering conditions.[5]

In this study, we report on the dependence on rf power of the structural, electrical and optical properties of tin-nitride films prepared by reactive sputtering. The chemical bonding states of tin and nitrogen in the films are also discussed.

Section snippets

Experimental

Tin-nitride films were prepared by an rf magnetron sputtering system. After a deposition chamber was evacuated below 3×10−4 Pa, nitrogen gas was introduced into the chamber. The nitrogen pressure was kept at 0.27 Pa, which corresponds to the mean free path of nitrogen in the plasma at 25 mm. We varied the rf power from 50 to 175 W. The substrate temperature was not maintained at a constant value and increased from room temperature up to about 40°C during deposition. The deposition conditions are

Crystal structure

Fig. 1 shows a typical XRD patterns for tin-nitride films. Some sharp diffraction peaks are observed and correspond to the Mirror indexes as noted in this figure. From their positions, we comfirm that the crystal structure of tin nitride belongs to an hexagonal system which has the lattice parameters of a=0.369 nm and c=0.529 nm. The preferred orientation is [001], which is not changed with the rf power.

The full width at half maximum (FWHM) of a diffraction peak is related to the crystallinity of

Conclusions

Polycrystalline tin-nitride thin films were deposited onto glass substrates by rf reactive sputtering. The basic physical properties, such as structural, electrical and optical properties were investigated. XPS measurements revealed the chemical bonding states and the composition of the deposited films. We obtained the binding energies of Sn3d and N1s as 486.1 eV and 396.5 eV, respectively, and the latter inplied the higher ionicity of the Sn–N bond in the tin-nitride films than that of Si–N in

References (13)

  • Y. Inoue et al.

    Proc. Symp. Plasma Sci. for Materials

    (1996)
  • R.S. Lima et al.

    Solid State Commun.

    (1991)
  • J.A. Taylor et al.

    J. Electron Spectrosc. and Related Phenomena

    (1978)
  • O. Takai

    Proc. SID

    (1987)
  • Y. Inoue et al.

    Proc. Symp. Plasma Sci. for Materials

    (1994)
  • T. Maruyama et al.

    J. Appl. Phys.

    (1995)
There are more references available in the full text version of this article.

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