Anodization of Al-Nd alloy films in nonaqueous electrolyte solutions for TFT-LCD application

The anodization behavior of Al-Nd alloys in nonaqueous electrolyte solution s and the electronic properties of the resultant anodic oxide films were st udied for TFT-LCD application. Sputtered Al-Nd alloy films on glass substra tes were anodized at 25 degreesC and 1 mA cm(-2) up to 100 V in ethylene gl ycol-water solutions containing 10 wt.% ammonium tartrate or salicylate to give uniform and flat oxide films. The incorporation of organic components into the anodic oxide films from the electrolyte solutions has lowered the relative permittivity and increased the breakdown electric field of the oxi de films. This was performed by decreasing the water content in the electro lyte solutions. The tartrate solution caused higher carbon incorporation th an the salicylate counterpart at the same water concentrations, giving lowe r relative permittivity, and higher forward breakdown electric field. The A l-O stretching frequency of the oxide films decreased slightly as the amoun t of incorporated organic moieties increased. Nd was uniformly distributed in the oxide films and an increase in the Nd content was likely to increase both the relative permittivity and the forward breakdown electric field wi thout any apparent change in the anodization behavior. (C) 2001 Elsevier Sc ience Ltd. All rights reserved.