METHOD FOR FORMING AN MTJ DEVICE

• Main Authors: CROTTI, Davide Francesco, GARELLO, Kevin
• Format: Patent
• Language: English; French; German
• Published: 23.02.2022
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INFORMATION STORAGE; PHYSICS; SEMICONDUCTOR DEVICES; STATIC STORES

According to an aspect there is provided a method for forming an MTJ device, comprising:forming a layer stack comprising an MTJ layer structure and a spin-orbit torque layer, SOT-layer, below the MTJ layer structure;forming a first etch mask over the layer stack, the first etch mask comprising a first mask line extending in a first horizontal direction;patterning the layer stack to form an MTJ line extending in the first horizontal direction, the patterning comprising etching while the first etch mask masks the layer stack, and stopping etching on or above the SOT-layer;forming sidewall spacers on either side of the MTJ line;while the sidewall spacers mask the SOT-layer, etching the SOT-layer to form a patterned layer stack comprising the MTJ line and a first patterned SOT-layer;forming a second etch mask over the patterned layer stack, the second etch mask comprising a second mask line extending in a second horizontal direction across the MTJ line; andpatterning the patterned layer stack to form a twice patterned SOT-layer, the twice patterned SOT-layer comprising an SOT-line extending in the second horizontal direction, and to form an MTJ pillar on the SOT-line, the patterning comprising etching while the second etch mask masks the patterned layer stack.