Semiconductor device and method for fabricating the same
A method for fabricating semiconductor device includes the steps of: forming a magnetic tunneling junction (MTJ) on a substrate; forming a liner on the MTJ; removing part of the liner to form a recess exposing the MTJ; and forming a conductive layer in the recess, wherein top surfaces of the conductive layer and the liner are coplanar. Preferably the MTJ further includes: a bottom electrode on the substrate, a fixed layer on the bottom electrode, and a top electrode on the fixed layer, in which the conductive layer and the top electrode are made of same material.
1. A method for fabricating semiconductor device, comprising:
forming a first inter-metal dielectric (IMD) on a substrate;
forming a first metal interconnection in the first IMD layer;
forming a first electrode layer, a fixed layer, and a second electrode layer on the first metal interconnection and the first IMD layer;
patterning the first electrode layer, the fixed layer, and the second electrode layer to form a MTJ comprising a bottom electrode and a top electrode, wherein a width of the top electrode is equal to a width of the fixed layer;
forming a liner on the top electrode;
removing part of the liner to form a recess exposing the top electrode; and
forming a conductive layer in the recess, wherein a top surface of the conductive layer is even with a top surface of the liner.
2. The method of claim 1 , further comprising:
forming the MTJ on the first metal interconnection;
forming a spacer around the MTJ;
forming a second IMD layer on the first IMD layer and around the spacer; and
forming the liner on the second IMD layer, the spacer, and the MTJ.
3. The method of claim 2 , further comprising:
removing part of the liner to form a recess exposing the MTJ, the spacer, and part of the second IMD layer;
forming the conductive layer in the recess; and
planarizing part of the conductive layer so that top surfaces of the conductive layer and the liner are coplanar.
4. The method of claim 2 , further comprising forming a second metal interconnection in the second IMD layer and adjacent to the MTJ before forming the liner.
5. The method of claim 4 , wherein top surfaces of the second metal interconnection and the second IMD layer are coplanar.
6. The method of claim 2 , wherein the MTJ comprises:
the bottom electrode on the first metal interconnection;
the fixed layer on the bottom electrode; and
the top electrode on the fixed layer.
7. The method of claim 6 , wherein the conductive layer and the top electrode comprise a same material.
8. The method of claim 6 , wherein the top electrode comprises:
a bottom portion in the second IMD layer; and
a top portion in the liner.