Magnetic components with perpendicular magnetic anisotropy maintaining high coercivity after high temperature annealing

Abstract

A magnetic tunnel junction (MTJ) in which a free layer has one interface formed with a tunnel barrier layer and a second interface formed with a metal oxide layer to facilitate its perpendicular magnetic anisotropy (PMA) . A diffusion barrier layer is formed on the side of the metal oxide layer opposite the second interface to prevent non-magnetic metals in the hard mask or electrodes from migrating to the second interface and to reduce the PMA of the free layer. Another diffusion barrier layer may be formed between the second electrode and the reference layer. The diffusion barrier layer can be a single layer of SiN, TiN, TaN, Mo, or CoFeX, where X is Zr, P, B, or Ta, or a multilayer such as CoFeX / Mo, where CoFeX contacts the metal oxide layer, and Mo Adjacent to the hard mask. Therefore, the coercivity in MTJs can be maintained or increased after annealing at 400 °C for 30 min.

Description

technical field [0001] This application relates to the following cases: U.S. Patent Publication No. 8,946,834; U.S. Patent Publication No. 9,006,704; and U.S. Patent Publication No. 2015 / 0008547, all assigned to a common assignee and incorporated herein by reference incorporated in this article. [0002] The present invention relates to magnetic devices utilizing magnetic tunneling junctions (MTJs) with perpendicular magnetic anisotropy (PMA), and in particular, relates to inserting a diffusion barrier layer between a capping layer and a top electrode to facilitate the annealing The coercive force (Hc) of the MTJ stack is maintained thereafter or during high temperature semiconductor steps of about 400°C. Background technique [0003] Magnetic random access memory (MRAM) has a read function based on the tunneling magnetoresistance (TMR) effect in an MTJ stack, wherein a tunneling barrier layer is formed between a free layer and a reference layer. While the reference layer ...

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Problems solved by technology

[0018] One problem caused by high temperature annealing around 400°C is that the hard mask material diffuses into the MTJ

Current technology fails to provide high Hc and thermal stability in a free layer with PMA characteristics that will withstand high temperature processing up to at least 400°C, which is required in semiconductor manufacturing methods

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