Semiconductor structure and manufacturing method therefor
A semiconductor structure includes: a substrate; a stacked structure, contact structures, and storage nodes. The stacked structure is located on the substrate and includes semiconductor layers extending in a first direction and arranged in a spaced manner in a second direction and in a third direction, wherein the first direction and the second direction are directions parallel to a plane where the substrate is located, the first direction is perpendicular to the second direction, and the third direction is a direction perpendicular to the plane where the substrate is located. The contact structures include a first end and a second end in the first direction, wherein the first ends of the contact structures are connected to the semiconductor layers, and a material of the contact structures includes metal silicide. The storage nodes extend in the first direction and are connected to a second end of respective contact structures.
1 . A semiconductor structure, comprising:
a substrate;
a stacked structure, located on the substrate and comprising semiconductor layers that extend in a first direction and are arranged in a spaced manner in a second direction and in a third direction, wherein the first direction and the second direction are directions parallel to a plane where the substrate is located, the first direction is perpendicular to the second direction, and the third direction is a direction perpendicular to the plane where the substrate is located;
contact structures, each contact structure comprising a first end and a second end in the first direction, wherein the first end of each contact structure is connected to a respective one of the semiconductor layers, and a material of the contact structures comprises metal silicide;
storage nodes, extending in the first direction, each storage node comprises a first electrode being connected to the second end of a respective one of the contact structures, a dielectric layer and a second electrode; wherein the first electrode has a cup shape with an opening in the first direction; the dielectric layer covers an inner wall and an outer wall of the first electrode; and the second electrode covers an inner wall and an outer wall of the dielectric layer; and
a conductive layer, covering an inner wall of the second electrode, filled in the capacitor holes and filled in a gap between any adjacent storage nodes.
2 . The semiconductor structure of claim 1 , wherein the material of the contact structures comprises cobalt silicide or titanium silicide.
3 . The semiconductor structure of claim 1 , further comprising:
a first support structure, covering sidewalls of the contact structures in the second direction and in the third direction, and filled between two adjacent contact structures.
4 . The semiconductor structure of claim 1 , further comprising:
capacitor holes, extending in the first direction,
wherein each storage node is located in a respective one of the capacitor holes.
5 . The semiconductor structure of claim 4 , wherein
the first electrode covers an inner wall of a capacitor hole;
the dielectric layer covers an inner wall of the first electrode and an end face of the first electrode that is far from the contact structure in the first direction; and
the second electrode covers an inner wall of the dielectric layer and is filled in the capacitor hole.
6 . The semiconductor structure of claim 5 , wherein
in the first direction, the stacked structure comprises a first area and a second area that are located on two sides of the contact structure;
the semiconductor structure further comprising:
first insulation layers, each first insulation layer being located between two adjacent semiconductor layers in the third direction within the first area; and
second insulation layers, each second insulation layer being located between two adjacent storage nodes in the third direction within the second area,
wherein a width of the second insulation layer in the third direction ranges from 5 nm to 10 nm.
7 . A method for manufacturing a semiconductor structure, comprising:
providing a substrate;
forming a stacked structure pre-layer on the substrate, wherein the stacked structure pre-layer comprises first semiconductor material layers and second semiconductor material layers, wherein both the first semiconductor material layers and the second semiconductor material layers extend in a first direction and a second direction, the first semiconductor material layers and the second semiconductor material layers are alternately stacked in a third direction, the third direction being a direction perpendicular to a plane where the substrate is located;
etching the stacked structure pre-layer to form a plurality of trenches penetrating the stacked structure pre-layer, wherein the trenches extend in the first direction; and forming vertical insulation layers in the trenches, wherein the first direction is a direction parallel to the plane where the substrate is located;
removing part of the second semiconductor material layers and part of the vertical insulation layers to form an opening extending in the second direction, wherein part of the first semiconductor material layers is exposed from the opening, and the second direction is parallel to the plane where the substrate is located and perpendicular to the first direction, wherein the opening divides the stacked structure pre-layer into a first area and a second area;
performing a silicification reaction on the first semiconductor material layer exposed from the opening to form contact structures, wherein the contact structures are used for connecting storage nodes, and a material of the contact structures comprises metal silicide;
removing first semiconductor material layers located in the second area by means of etching to form capacitor holes, the first semiconductor material layers in the first area being formed into semiconductor layers; and
forming a storage node in each of the capacitor holes, wherein the storage node comprises a first electrode, a dielectric layer and a second electrode, and the first electrode extends in the first direction and is connected to a respective one of the contact structures.
8 . The method of claim 7 , wherein the material of the contact structures comprises cobalt silicide or titanium silicide.
9 . The method of claim 7 , wherein after the contact structures are formed, the method further comprises:
filling a first support structure in the opening, wherein the first support structure covers sidewalls of the contact structures in the second direction and in the third direction.
10 . The method of claim 7 , wherein after the opening is formed, the method further comprises:
remaining second semiconductor material layers are removed by means of etching; and
forming insulation layers at positions where the second semiconductor material layers are removed by means of etching, wherein the insulation layers comprise first insulation layers located in the first area and second insulation layers located in the second area.
11 . The method of claim 10 , wherein the forming a storage node in each of the capacitor hole comprises:
forming the first electrode on an inner wall of the capacitor hole;
forming the dielectric layer on an inner wall of the first electrode and an end face of the first electrode that is far from the contact structure in the first direction; and
forming the second electrode on an inner wall of the dielectric layer, wherein the second electrode is filled in the capacitor hole.
12 . The method of claim 11 , wherein before the storage node is formed, the method further comprises:
thinning the second insulation layers to cause a width of thinned second insulation layers in the third direction to range from 5 nm to 10 nm.
13 . The method of claim 10 , wherein the forming a storage node in each of the capacitor holes comprises:
forming the first electrode on an inner wall of the capacitor hole, wherein the first electrode has a cup shape with an opening in the first direction;
forming the dielectric layer on an inner wall and an outer wall of the first electrode; and
forming the second electrode on an inner wall and an outer wall of the dielectric layer.
14 . The method of claim 13 , further comprising:
after the first electrode is formed, removing the second insulation layers and vertical insulation layers in the second area by means of etching; and
after the second electrode is formed, forming a conductive layer on an inner wall of the second electrode and a gap between any adjacent storage nodes, wherein the conductive layer is filled in the capacitor holes.