Magnetic tunnel junction manufacturing method

Abstract

The invention discloses a manufacturing method of a magnetic tunnel junction. According to the invention, an etching device used in the method comprises a sample loading chamber, a vacuum transition chamber, a reactive ion plasma etching chamber, an ion beam etching chamber, a film coating chamber and a vacuum transmission chamber, and under the condition of not interrupting vacuum, the reactive ion plasma etching chamber, the ion beam etching chamber and the film coating chamber are combined to perform etching, cleaning and film coating protection on a magnetic tunnel junction; with the method, device damage and contamination can be effectively reduced, the influence caused by over-etching is avoided, the device performance is improved, and the steepness of an etched pattern can be precisely controlled so as to obtain a pattern result meeting the performance requirement.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a method for manufacturing a magnetic tunnel junction. Background technique [0002] The magnetic tunnel junction is the core structure of the magnetic random access memory, including a cap layer, a fixed layer, a non-magnetic isolation layer and a free layer. The bottom of the free layer can be a bottom electrode metal layer or a dielectric layer. Among them, the fixed layer is thicker, has stronger magnetism, and the magnetic moment is not easy to reverse, while the free layer is thinner, weaker in magnetism, and the magnetic moment is easy to reverse. Since the magnetic tunnel junction material is Fe, Co, Mg, etc., which are difficult to dry etch, it is difficult to form volatile products, and the corrosion gas Cl cannot be used. 2 etc., otherwise it will affect the performance of the magnetic tunnel junction, so it needs to use a relatively complicated etching method to realize...

AI Technical Summary

Problems solved by technology

However, reactive ion etching has some problems in magnetic tunnel junction etching

The etching process of reactive ion etching includes chemical etching and physical etching. Chemical etching will cause chemical damage to the sidewall of the magnetic tunnel junction, which will affect the magnetic properties of the magnetic tunnel junction and device performance.

In addition, low physical bombardment etching during etching may cause secondary deposition on the sidewall and bottom of the magnetic tunnel junction, resulting in metal contamination, especially when the metal contamination occurs on the isolation layer, which will directly cause the insulating layer of the device to be guided. pass, loss of device function

Images