Method for preparing capacitor with Ta205 thin film as dielectric film

Abstract

The invention discloses a method for preparing a capacitor with a Ta205 thin film as a dielectric film and comprises the following steps of: plating a lower electrode on a substrate in need of preparation of a thin film capacitor, plating a dielectric thin film on the formed lower electrode, and plating an upper electrode of the capacitor on the dielectric thin film, wherein the step of plating the dielectric thin film comprises: providing a vacuum cavity, wherein a Ta205 target and a substrate with the lower electrode are arranged in the vacuum cavity; introducing mixed gas of oxygen with volume content of 0.1 to 20 percent and argon, and regulating the working air pressure to be between 0.2 and 2Pa; and forming aTa205 thin film layer on the substrate to be plated by a magnetron sputtering method. According to the method, the Ta205 target is directly sputtered at the room temperature, and heat treatment is not required. The process is simple and convenient to operate, and new generation DRAM products with high storage density can be developed and produced in large scale.

Description

technical field [0001] The invention relates to a method for preparing a capacitor, in particular to a method for preparing a film dielectric capacitor. Background technique [0002] As the feature size of semiconductor devices continues to shrink according to Moore's law, in order to ensure the same performance of the device or the necessary capacitor capacity, the thickness of the required dielectric film layer must also be reduced in a corresponding proportion. The Si-based compound thin film is prone to defects such as porous morphology and oxygen vacancies, which cause problems such as tunneling leakage current, and affect the performance of semiconductor devices or storage devices DRAM. Therefore, the preparation of flat, compact and high dielectric constant oxide films has become an important process link in the upgrading of semiconductor devices and increasing the capacity of film capacitors. In recent years, Ta 2 o 5 Thin films have attracted much attention in th...

AI Technical Summary

Problems solved by technology

The important problem that needs to be solved is to determine and distinguish the type of defects, whether it is the imbalance of chemical composition in the film (such as oxygen deficiency) caused by improper process, or the imperfect crystallization caused by insufficient growth conditions.