Preparation Of High Dielectric Constant Composite Dielectric Film

Recent development of small electronic devices requires increasement in capacitance of aluminum electrolytic capacitors. Higher capacitance can be obtained with enlarging surface area of aluminum foils and increasing the dielectric constant of dielectric films on aluminum foils. The main goal of this paper is to investigate the mechanism of the increasing in dielectric constant for increasing capacitance of aluminum foils used in low-voltage aluminum electrolytic capacitors. The important results and innovations are as follows:1. The fabricating technologies of high dielectric constant oxide films composes valve metal oxide and Al2O3 were studied.To increasing the capacitance of Aluminum foils, increasment in the dielectric constant of dielectric films is an important method. This paper studied a series of technologies, which are compatible with the traditional etching and formation linkage line, for fabricating high dielectric constant oxide films on aluminum foils. And the corresponding mechanism of these technologies was also studied.Forming Al-value metal composite oxide films by single inorganic salt hydrolyzation was proposed and studied. The capacitance of Aluminum foils is increased in ratio of 32.5% at the rated withstanding voltage of 51V. The technology was put in for Chinese patent.2. The fabricating technologies of high dielectric constant multifarious oxide films composes multifarious oxide and Al2O3 were studied.To form multifarious metal composite oxide films on the basis of inorganic salt hydrolyzation process was proposed and studied. The capacitance of Aluminum foils is increases as much as the single inorganic salt hydrolyzation process.The differentia of the first and scend methods is studied. 3.The useness of chelations in solution to deal with etched foils was studied. Adding chelations in solution to avoid hydrolyzing before to deal with the etched foils. There are some reasons: to avoid hydrolyzing of the cation in solution, to give facilities for the soakage to the surface of etched foils, to decrease the size of crystals.