Optical characteristics of thin rf sputtered Ta2O5layers

✍ Scribed by Babeva, Tz. ;Atanassova, E. ;Koprinarova, J.

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 117 KB
• Volume: 202
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200406915

✦ Synopsis

Abstract

The optical properties of rf sputtered (30; 52 nm) Ta~2~O~5~ before and after O~2~ annealing at 1173 K have been investigated in the terms of storage capacitor applications for high density dynamic memories. Refractive index and thickness of the films are determined from transmittance and reflectance measurements at normal light incidence in the spectral range 400–800 nm. The film density explored by refractive index is improved with increasing film thickness as well as after annealing. The optical band gap is found to be 4.20 eV for 30 nm and 4.12 eV for 52 nm Ta~2~O~5~ regardless of the amorphous status of the layers‐amorphous (as‐deposited) or polycrystalline (annealed layers). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)