Patent ID: 7122386

Claim:
A method of forming bit line contacts in an MRAM structure, comprising: (a) providing a substrate comprised of a word line, word line pad, word line contact, and word line interlayer dielectric (ILD) layer that are coplanar; (b) depositing a first etch stop layer on the substrate and forming an opening in said first etch stop layer that exposes the word line contact; (c) sequentially depositing a bottom electrode layer, MTJ stack, and hard mask on the first etch stop layer and exposed portion of the word line contact; (d) selectively removing portions of the hard mask and MTJ stack to form an MTJ element and overlying hard mask that are aligned above the word line; (e) selectively removing portions of the bottom electrode layer to form an opening directly above the word line pad and directly above a bonding pad region thereby forming a bottom electrode below the MTJ element and on said word line contact; (f) sequentially forming an MTJ ILD layer, second etch stop layer, and bit line ILD layer on the bottom electrode, hard mask, and first etch stop layer; (g) forming a first trench in the second etch stop layer and bit line ILD layer above the word line pad, a second trench that exposes the hard mask on the MTJ element, a third trench above the bond pad region, and forming a via between the word line pad and first trench and between the bonding pad region and third trench; and (h) forming a bit line above the MTJ element, a bit line contact comprised of a dual damascene structure in the first trench and via above the word line pad, and a bit line contact comprised of a dual damascene structure in the third trench and via above the bonding pad region.