Magnetic tunnel junction contact electrode and forming method therefor

Abstract

The invention provides a magnetic tunnel junction contact electrode and a forming method therefor, and the contact electrode comprise a ruthenium contact film layer and a seed layer. The forming method comprises the steps: S1, providing a substrate which comprises a bottom electrode, a first electric dielectric layer, an MTJ structure unit, a tantalum top electrode and a second electric dielectric layer; S2, forming a contact electrode film layer and a hard mask film layer on the substrate; S3, carrying out the patterned transferring of a contact electrode pattern to the hard mask film layer; S4, carrying out the etching of the hard mask film layer; S5, carrying out the etching of the contact electrode film layer; S6, growing a third electric dielectric layer, and filling a contact electrode with the third electric dielectric layer; S7, grinding the surface of the contact electrode till all the hard mask film layer is ground off; S8, forming a top electrode connection hole on the contact electrode etching barrier layer and a fourth electric dielectric layer; S9, carrying out the patterned defining and etching to form a top electrode connection hole; S1, forming a diffusion termination layer in the top electrode connection hole; S11, carrying out the filling of the top electrode connection hole; S12, grinding the top electrode connection hole.

Description

technical field [0001] The invention relates to a magnetic tunnel junction (MTJ, Magnetic Tunnel Junction), in particular to a magnetic tunnel junction contact electrode and a forming method thereof, belonging to the technical field of integrated circuit manufacturing. Background technique [0002] In recent years, Magnetic Random Access Memory (MRAM, Magnetic Radom Access Memory) using the magnetoresistance effect of Magnetic Tunnel Junction (MTJ) is considered to be the future solid-state non-volatile memory, which has high-speed reading and writing, large capacity and low energy consumption. consumption characteristics. Ferromagnetic MTJ is usually a sandwich structure, which has a magnetic memory layer, which can change the magnetization direction to record different data; an insulating tunnel barrier layer in the middle; a magnetic reference layer, located on the other side of the tunnel barrier layer, which The direction of magnetization remains unchanged. [0003] I...

AI Technical Summary

Problems solved by technology

In order to reduce the resistance of the loop, the cross-section of the TEV is usually made very large. However, in the process of preparing the TEV, fluorocarbon gases (such as C 4 f 8 、CF 4 、CHF 3 and CH 2 f 2 etc.), this gas can easily etch or damage the dielectric filled around the MTJ and tantalum (Ta) top electrode, thereby increasing the risk of leakage between the MTJ and the top electrode connection hole (TEV)

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