Method for fabricating ferroelectric random access memory device

Abstract

The present invention relates to a method for fabricating a ferroelectric random access memory device. The method includes the steps of: (a) forming a first inter-layer insulation layer on a substrate providing a transistor; (b) etching the first inter-layer insulation layer to form a storage node contact hole exposing a partial portion of the substrate; (c) burying a storage node contact including a plug and a barrier metal layer into the storage node contact hole; (d) forming an adhesion layer on the storage node contact and the first inter-layer insulation layer; (e) inducing a predetermined portion of the adhesion layer to be cracked, the predetermined portion disposed above an upper part of the plug; (f) selectively removing the cracked predetermined portion to expose a surface of the barrier metal layer formed on the plug; and (g) forming a ferroelectric capacitor connected to the plug through the exposed surface of the barrier metal layer.

Description

technical field [0001] The invention relates to a manufacturing method of a semiconductor device, in particular to a manufacturing method of a ferroelectric random access memory (FeRAM). Background technique [0002] How to use the ferroelectric layer to form a ferroelectric capacitor to develop a large-scale semiconductor memory device and overcome the inherent refresh bottleneck of dynamic random access memory (DRAM) has always been a research hotspot. This FeRAM, made using a ferroelectric layer, is a type of non-volatile memory. This means that FeRAM has an inherent advantage of being able to read its data even when the power is turned off. At the same time, FeRAM has become the focus of attention as a candidate for next-generation memory due to its response speed comparable to that of DRAM. [0003] The upper and lower electrodes of ferroelectric capacitors generally use materials with good conductivity, such as Pt, Ir, and Ru. However, when this noble metal is used ...

AI Technical Summary

Problems solved by technology

The oxide layer on the third titanium nitride layer may increase the leakage current

This leads to the easy diffusion of oxygen to the titanium nitride layer during the high-temperature crystallization heat treatment process of the ferroelectric layer, resulting in the oxidation of the titanium nitride layer.

As a result, the oxidized TiN leads to an increase in leakage current, which in turn leads to an increase in the contact resistance between the bottom electrode and the tungsten plug

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