Protective layers for MRAM devices

A method for forming a magnetoresistive memory on a semiconductor substrate having an underlying integrated circuit component, comprising, in sequence:

• forming a plurality of protrusions comprising magnetoresistive memory layers with a capping layer as an uppermost layer;
• depositing a conformal layer of spacer material over the plurality of protrusions;
• performing a spacer etch on the layer of spacer material, thereby forming spacers along side surfaces of the protrusions;
• forming a layer of insulating material over the protrusions, the spacers and the substrate;
• removing the insulating material at least over the protrusions;
• selectively etching the capping layer;
• and
• performing a metallization process to make contact to the magnetoresistive memory layers.

A method of forming a magnetic memory cell, comprising:

• forming a stack of magnetic memory layers with a stud structure and having a topmost layer comprising a sacrificial cap;
• providing a continuous first insulator layer over and around the stud structure;
• removing the first insulator layer at least over the stud structure, thereby exposing the sacrificial cap, wherein removing the insulator layer at least over the stud structure comprises chemical mechanical planarization of the insulator layer to expose the sacrificial cap;
• removing the exposed sacrificial cap using a selective etch, where the selective etch preferentially removes material from the sacrificial cap at a faster rate than material from the first insulator layer, where the selective etch is applied to the sacrificial cap and to at least an exposed portion of the first insulator layer so that corners of a recess in the first insulator layer that is defined by the removed sacrificial cap are rounded;
• and
• supplying an electrical connection to the magnetic memory layers.

A method of forming a tunneling magnetoresistive (TMR) memory cell, comprising:

• forming a TMR structure with a cap layer at a top surface, the TMR structure with the cap layer protruding as a stud from a substrate;
• depositing a first dielectric layer over and around the stud;
• planarizing a top surface of the first dielectric layer and the stud;
• depositing a second dielectric layer over the first dielectric layer and the stud;
• etching a trench entirely through the second dielectric layer to the cap layer with a first etch;
• removing the cap layer with a second etch, where the second etch preferentially removes material from the cap layer at a faster rate than material from the second dielectric layer or material from the first dielectric layer;
• and
• depositing metal to fill the trench and an opening left after removing the cap layer.