Semiconductor device having a copper plug

摘要

Disclosed is a semiconductor device wherein an insulation layer has a via opening with an aluminum layer in the via opening and in contact with the last wiring layer of the device. There is a barrier layer on the aluminum layer followed by a copper plug which fills the via opening. Also disclosed is a process for making the semiconductor device.

主权项

1. A semiconductor device comprising:
a semiconductor substrate having a plurality of wiring layers wherein a last wiring level comprises a conductive material; an insulation layer formed on the last wiring layer, the insulation layer having a via opening formed therein to expose the conductive material in the last wiring layer, the via opening extending to a full thickness of the insulation layer; an aluminum layer in the via opening extending to a height above the full thickness of the insulation layer and the entire via opening, the aluminum layer having a wall and a bottom; a barrier layer formed on the aluminum layer, the barrier layer having a wall and a bottom coextensive with the aluminum layer wall and bottom; and a copper plug formed on the barrier layer and in contact with all of the barrier layer wall and bottom and filling the entire via opening, the copper plug extending to the height above the full thickness of the insulation layer.