Memory device and method for manufacturing the same
A semiconductor structure and a method for manufacturing the same are disclosed. The semiconductor structure includes a first electrode layer, a second electrode layer and a dielectric layer between the first electrode layer and the second electrode layer. A width of the second electrode layer becomes larger in a direction away from the dielectric layer.
1. A memory device, comprising:
a first electrode layer;
a second electrode layer;
a dielectric layer having an ONO structure and disposed between the first electrode layer and the second electrode layer, wherein a width of the second electrode layer becomes larger in a direction away from the dielectric layer;
wherein the memory device is a 3D stacked memory device comprising a plurality of stack structures each of which comprises at least one of the first electrode layer and the second electrode layer is disposed between the stack structures and on opposing sides of the first electrode layers disposed in two adjacent stack structures; and
wherein the dielectric layer conformally covers on one of the stack structures and is disposed on opposing walls of the first electrode layer.
2. The memory device according to claim 1 , wherein the second electrode layer comprises a first electrode portion and a second electrode portion, the first electrode portion is between the second electrode portion and the dielectric layer, materials of the first electrode portion and the second electrode portion have different characteristics.
3. The memory device according to claim 2 , wherein a dopant concentration of the first electrode portion is lower than a dopant concentration of the second electrode portion.
4. The memory device according to claim 2 , wherein a dopant concentration of the first electrode portion becomes lower in a direction toward the dielectric layer.
5. The memory device according to claim 1 , wherein the second electrode layer comprises a first electrode portion and a second electrode portion, the first electrode portion is between the second electrode portion and the dielectric layer, the second electrode portion has a fixed width.
6. The memory device according to claim 1 , wherein the second electrode layer comprises a first electrode portion adjoined with the dielectric layer, a width of the first electrode portion becomes larger in the direction away from the dielectric layer.
7. The memory device according to claim 1 , wherein the second electrode layer has a first sidewall adjoined with the dielectric layer, and a flat second sidewall adjoined with the first sidewall and separated from the dielectric layer.
8. The memory device according to claim 1 , wherein the second electrode layer has a first sidewall adjoined with the dielectric layer, and a concave second sidewall adjoined with the first sidewall and separated from the dielectric layer.
9. The memory device according to claim 1 , wherein the second electrode layer has a first sidewall adjoined with the dielectric layer, and a convex second sidewall adjoined with the first sidewall and separated from the dielectric layer.
10. The memory device according to claim 1 , wherein the second electrode layer has a first sidewall adjoined with the dielectric layer, and a second sidewall adjoined with the first sidewall and separated from the dielectric layer, an included angle between the first sidewall and the second sidewall is bigger than 90 degrees.