Methods of metal oxide dielectric films testing

摘要

In the bulk of the dielectric anodic film Ta/sub 2/O/sub 5/ (Nb/sub 2/O/sub 5/) and in the vicinity of the interface with tantalum (niobium), there are structural defects which create channels of increased conductivity and affect the leakage current of tantalum capacitors. The nature, concentration and electrical activity of the structural defects of an anodic film are determined by the composition and structure of the surface layer of the tantalum, the conditions of formation of the oxide layer, the material and the method of formation of the cathode material. The author presents a number of experimental techniques for detecting, in an amorphous oxide dielectric, structural defects which accelerate film destruction processes in a strong electric field and thus are potentially dangerous under prolonged thermoelectric stresses applied to capacitor structures. These techniques are based on structure-sensitive electrical phenomena in amorphous metal oxide dielectrics.