Advanced MRAM device structure having hyperboloid shape
A MRAM Cell including a dielectric cap and a lower section that includes a bottom electrode, a synthetic anti-ferromagnet layer, and a reference layer, where in the sidewalls of each of the bottom electrode, the synthetic anti-ferromagnet layer, and the reference layer are angled relative to the vertical plane perpendicular to a top surface of the dielectric cap. A first dielectric liner located on the sidewalls of each of the lower section. An upper section that includes a tunnel barrier, a free layer, and a top electrode. A second dielectric liner located on a side section of the tunnel barrier, where the second dielectric liner is comprised of a second material, and where the angled side sections of the tunnel barrier are located on top of the second dielectric liner.
1 . An MRAM cell comprising:
the MRAM cell having an hourglass shape, wherein the hourglass shape is defined by a plurality of layers, wherein the MRAM cell is comprised of a lower section and an upper section, where the lower section of the MRAM cell is comprised a bottom electrode, a synthetic anti-ferromagnet layer, and a reference layer.
2 . The MRAM cell of claim 1 , wherein a top surface of the reference layer has a first width, and a bottom surface of the reference layer has a second width, and wherein the first width is less than the second width.
3 . The MRAM cell of claim 2 , wherein a top surface of the synthetic anti-ferromagnet layer is substantial equal to the second width and a bottom surface of the synthetic anti-ferromagnet layer has a third width, and wherein the second width is less than the third width.
4 . The MRAM cell of claim 3 , wherein a top surface of the bottom electrode is substantial equal to the third width and a bottom surface of the bottom electrode has a fourth width, and wherein the third width is less than the fourth width.
5 . The MRAM cell of claim 4 , further comprising:
a dielectric cap, wherein the MRAM cell is located on top of the dielectric cap, wherein a sidewall of each the bottom electrode, the synthetic anti-ferromagnet layer, and the reference layer are at an angle relative to a vertical plane perpendicular to a top surface of the dielectric cap.
6 . The MRAM cell of claim 5 , wherein the angle of the sidewalls of each the bottom electrode, the synthetic anti-ferromagnet layer, and the reference layer is in a range of about 30 to 75 degrees relative to the vertical plane perpendicular to a top surface of the dielectric cap.
7 . The MRAM cell of claim 6 , further comprising:
a first dielectric liner located on the sidewalls of each the bottom electrode, the synthetic anti-ferromagnet layer, and the reference layer, respectively.
8 . The MRAM cell of claim 7 , further comprising:
where the upper section of the MRAM cell is comprised a tunnel barrier, a free layer, and a top electrode.
9 . The MRAM cell of claim 8 , wherein a shape of the upper section mirrors the shape of the lower section.
10 . The MRAM cell of claim 9 , further comprising:
a second dielectric liner located along a sidewall of the tunnel barrier layer.
11 . An MRAM Cell comprising:
a dielectric cap;
a lower section located on top of the dielectric cap, wherein the lower section includes/comprises a bottom electrode, a synthetic anti-ferromagnet layer, and a reference layer, wherein in a sidewall of each of the bottom electrode, the synthetic anti-ferromagnet layer, and the reference layer are angled relative to the vertical plane perpendicular to a top surface of the dielectric cap;
a first dielectric liner located on the sidewalls of each of the bottom electrode, the synthetic anti-ferromagnet layer, and the reference layer, wherein the first dielectric liner is comprised of a first material;
an upper section that includes a tunnel barrier, a free layer, and a top electrode, wherein the tunnel barrier has a horizontal bottom section located on top of the reference layer, wherein the tunnel barrier has angled vertical sided sections;
a second dielectric liner located on a side section of the tunnel barrier, wherein the second dielectric liner is comprised of a second material, and wherein the angled side sections of the tunnel barrier are located on top of the second dielectric liner.
12 . The MRAM cell of claim 11 , wherein the first material and the second material are the same.
13 . The MRAM cell of claim 11 , wherein the first material and the second material are different.
14 . The MRAM cell of claim 11 , wherein a top surface of the reference layer has a first width and a bottom surface of the reference layer has a second width, and wherein the first width is less than the second width.
15 . The MRAM cell of claim 14 , wherein a top surface of the synthetic anti-ferromagnet layer is substantial equal to the second width and a bottom surface of the synthetic anti-ferromagnet layer has a third width, and wherein the second width is less than the third width.
16 . The MRAM cell of claim 15 , wherein a top surface of the bottom electrode is substantial equal to the third width and a bottom surface of the bottom electrode has a fourth width, and wherein the third width is less than the fourth width.
17 . An MRAM cell comprising: the MRAM cell having a hyperboloid shape, wherein the hyperboloid shape is defined by a plurality of layers, wherein the MRAM cell is comprised of a lower section and an upper section, wherein the location where the lower and upper section width narrows at a location where the lower and upper section are in contact with each other, where the lower section of the MRAM cell is comprised of a bottom electrode, a synthetic anti-ferromagnet layer, and a reference layer.