Semiconductor device and method for fabricating the same
A method for fabricating semiconductor device includes the steps of: forming a first magnetic tunneling junction (MTJ) on a substrate; forming a first ultra low-k (ULK) dielectric layer on the first MTJ; performing a first etching process to remove part of the first ULK dielectric layer and form a damaged layer on the first ULK dielectric layer; and forming a second ULK dielectric layer on the damaged layer.
1 . A method for fabricating semiconductor device, comprising:
forming a first magnetic tunneling junction (MTJ) on a substrate;
forming a first ultra low-k (ULK) dielectric layer on the first MTJ, wherein a top surface of the first ULK dielectric layer comprises a curve;
performing a first etching process to remove part of the first ULK dielectric layer, transform the curve into a V-shape, and form a damaged layer on the first ULK dielectric layer; and
forming a second ULK dielectric layer on the damaged layer.
2 . The method of claim 1 , wherein the first etching process comprises bombarding nitrogen gas (N 2 ) into the first ULK dielectric layer to form the damaged layer.
3 . The method of claim 1 , further comprising:
forming the first MTJ and a second MTJ on the substrate
forming the first ULK dielectric layer on the first MTJ and the second MTJ and forming a first opening between the first MTJ and the second MTJ;
performing the first etching process to form a second opening between the first MTJ and the second MTJ; and
performing a second etching process to remove part of the first ULK dielectric layer to form a third opening between the first MTJ and the second MTJ before forming the second ULK dielectric layer.
4 . The method of claim 3 , wherein a width of the first opening is less than a width of the second opening.
5 . The method of claim 3 , wherein a width of the second opening is less than a width of the third opening.