Carlos E. Viana, Ana Neilde R. da Silva and Nilton I. Morimoto, LSI-DMI-EPUSP.
In this work is studied the influence of the argon flux addition to the total gas feed in the plasma enhanced chemical vapour deposition process of silicon oxide thin films using TEOS as silicon source. This process is performed aiming at improve the electrical characteristics of the films for TFT's and smart sensor applications.
The Optical Emission Spectroscopy was used for the plasma characterization. The thickness and refractive index of the silicon oxide thin films were obtained by ellipsometry, the chemical bonds were evaluated by FTIRS (Fourier Transformed Infra Red Spectroscopy) and the carbon contamination of the films was obtained by µ-RAMAN. The silicon/silicon oxide interface was analyzed by AFM (Atomic Force Microscopy).
The optical emission of CO and O increases as the Ar flux increases showing that the TEOS oxidation process is improved with the Ar flux. Through FTIRS the silicon oxide stretching, bending and rocking absorbance bands is observed, the Si-OCH3 absorbance bands are also observed and its intensity varies with Ar flux. The Si-OH and free -OH absorbance bands are not observed in this films indicating low hidrogen incorporation.
Organic contamination was observed by µ-Raman analyses as small black points distributed Through the silicon oxide thin films which are attributed to C=C bonds. The density of these points decreases as the Ar flow added to the total gas flow increases. We conclude that there is an improvement in the silicon oxide thin films structural characteristics with the addition of a controlled Ar flux to the total flux.
XX CONGRESSO BRASILEIRO DE APLICAÇÕES DE VÁCUO NA INDÚSTRIA E NA CIÊNCIA - XX CBRAVIC.
28 A 30 DE JULHO DE 1999 - IFUSP - SÃO PAULO-SP.