초록 ▼

The invention describes the application of copper damascene connectors to a double level metal process. A dual damascene copper connector whose upper surface is coplanar with the upper surface of the insulating layer in which it is embedded is described. Out-diffusion of copper from the connector is

The invention describes the application of copper damascene connectors to a double level metal process. A dual damascene copper connector whose upper surface is coplanar with the upper surface of the insulating layer in which it is embedded is described. Out-diffusion of copper from the connector is prevented by at least two barrier layers. One or two barrier layers are located at the interface between the connector and the insulating layer while another barrier layer comprises conductive material and covers the upper surface of the connector. When a second damascene connector is formed above the first connector the conductive barrier layer facilitates good contact between the two connectors. It also acts as an etch stop layer during the formation of the second connector. A process for manufacturing this structure is also described. It involves over-filling a trench in the surface of the insulator with copper and then removing the excess by chem.-mech. polishing.

대표청구항 ▼

A method for manufacturing a double layered copper connector comprising: (a) providing a partially completed integrated circuit; (b) depositing a first insulating layer, having an upper surface, on said integrated circuit; (c) patterning and then etching said first insulating layer to form a cavity

A method for manufacturing a double layered copper connector comprising: (a) providing a partially completed integrated circuit; (b) depositing a first insulating layer, having an upper surface, on said integrated circuit; (c) patterning and then etching said first insulating layer to form a cavity extending down to the level of said integrated circuit; (d) depositing a first barrier layer on the walls of said cavity and on the upper surface said first insulating layer; (e) patterning and etching said first barrier layer so that it extends for some distance, on the upper surface of said first insulating layer, on all sides of the cavity; (f) depositing a second insulating layer, having upper and lower surfaces, on the upper surface of said first insulating layer; (g) patterning and then etching said second insulating layer to form a trench therein, said trench being narrower than said extension of the first barrier layer, wider than said cavity, and symmetrically disposed over said cavity; (h) depositing a second barrier layer on the walls of both the trench and the cavity and on the upper surface of said second insulating layer; (i) depositing a copper layer to more than fill said cavity and said trench; (j) removing said copper layer and said second barrier layer to the level of the upper surface of said second insulating layer, thereby forming a first dual damscene copper connector having an upper surface; (k) depositing an etch stop barrier layer on the upper surface of the second insulating layer and on the upper surface of said damascene connector; (l) patterning and etching said etch stop barrier layer so that it slightly overlaps said upper surface of said damascene connector; and (m) forming a second dual damascene connector, disposed directly above the first dual damascene connector, in the manner recited in steps (b) through (j) above.