Patent ID: 7312131

Claim:
A method for forming a multilayer electrode capacitor, comprising: (a) forming a trench in a substrate; (b) at least forming a first conductive layer, a dielectric layer, and a second conductive layer on an inner surface of the trench in sequence; (c) removing a portion of the first conductive layer, a portion of the dielectric layer and a portion of the second conductive layer above the top of the trench, and wet etching the first conductive layer, the dielectric layer and the second conductive layer to generate a first distance between a top of the first conductive layer and a top of the trench, and a second distance between a top of the second conductive layer and the top of the trench, wherein the first distance is greater or smaller than the second distance; (d) forming a first insulating layer, wherein when the first distance is greater than the second distance, the first insulating layer covers the first conductive layer and exposes the second conductive layer, and when the second distance is greater than the first distance, the first insulating layer covers the second conductive layer and exposes the first conductive layer; (e) forming a first connecting layer to connect electrically with the exposed second conductive layer, or electrically connect with the exposed first conductive layer; (f) removing a portion of the first connecting layer and a portion of the first insulating layer to expose a portion of the first conductive layer and a portion of the second conductive layer; (g) performing a surface treatment to transform an exposed surface of the first conductive layer into first conductive surface and to transform an exposed surface of the second conductive layer into second insulating surface when the first connecting layer electrically connects with the second conductive layer, or to transform exposed surface of the first conductive layer into first insulating surface and to transform an exposed surface of the second conductive layer into second conductive surface when the first connecting layer electrically connects with the second conductive layer; and (h) forming a second connecting layer to connect electrically with the second conductive layer with the second conductive surface, or to connect with the first conductive layer with the first conductive surface, wherein the second connecting layer is insulated from the first connecting layer and the first conductive layer with the first insulating surface, or the second conductive layer with the second insulating surface.