Tantalum pentoxide dielectric prond. thin film technique - using electrolytic treatment in anhyd. alcoholic metal salt soln

摘要

The prodn. of a Ta2O5 dielectric in the thin film technique, esp. a dielectric for capacitive elements in thin film circuits, is carried out by the following stages: (a) deposn. of a Ta coating on the entire surface of an electrically insulating substrate plate; (b) etching a network for electric elements and conductors in the Ta film, using a photographic technique; (c) anodic oxidn. of individual areas of the Ta film for capacitive structures; (d) electrolytic after-treatment of the Ta2O5 dielectric; and (e) renewed anodic oxidn. of the Ta2O5 dielectric film. The electrolytic after-treatment comprises immersing the Ta2O5 dielectric as cathode in an anhyd. alcoholic metal salt soln. as electrolyte and applying a potential of 1.0-4 V, corresp. to 0.5-2% of that used in anodic oxidn., for 10-60 min. The no. of flaws in the dielectric is reduced without the occurrence of incidental surface or capacity losses.