TANTAL OXIDE CAPACITOR HAVING HIGH CAPACITANCE

摘要

A thin film capacitor for use in an integrated circuit includes a lower plate disposed on the silicon substrate of the integrated circuit. The lower plate comprises a barrier layer of conductive material which prevents transport of silicon from the silicon substrate into a layer of dielectric material which is disposed between the lower plate and an upper plate. A portion of the barrier layer can be consumed and transferred into dielectric material by, for example, high temperature oxidation which generates a symmetric series capacitor with the dielectric layer. A layer comprising an oxide of the barrier layer material is formed between the barrier layer and the dielectric layer by consuming an upper portion of the barrier layer. The capacitor is constructed by forming the barrier layer on at least a portion of the silicon substrate, forming the dielectric layer over an upper surface of the barrier layer, oxidizing the upper surface of the barrier layer and forming a layer of electrically conductive material on an upper surface of the dielectric layer.