Patent ID: 7259059
Filing Date: 2007-08-21
Classification: C23C,H01L

Abstract:
1. A method for forming a capacitor of semiconductor device, the method comprising the steps of: forming a storage electrode; depositing HfxAlyOz thin films on the storage electrode to form an HfxAlyQz dielectric film; and forming a plate electrode on the HfxAlyOz dielectric film, wherein the HfxAlyOz dielectric film consists of compositionally graded HfxAlyOz thin films which are different in compositions of Hf and Al such that the lower HfxAlyOz thin film adjoining the storage electrode has a larger composition ratio of Al than that of Hf and the upper HfxAlyOz thin film has a larger composition ratio of Hf than that of Al. and the upper HfxAlyOz thin film is subjected to heat treatment under an oxygen atmosphere after its deposition.