Semiconductor devices and methods for manufacturing the same
View Patent ↗Semiconductor devices having a copper line layer and methods for manufacturing the same are disclosed. An illustrated semiconductor device comprises a damascene insulating layer having a contact hole, a barrier metal layer including a first ruthenium layer, a ruthenium oxide layer and a second ruthenium layer, a seed copper layer formed on the barrier metal layer, and a copper line layer made of a Cu—Ag—Au solid solution. A disclosed example method of manufacturing a semiconductor device reduces and/or prevents contact characteristic degradation of the barrier metal layer with the silicon substrate or the damascene insulating layer. In addition, by forming the copper line layer made of the Cu—Ag—Au solid solution, long term device reliability may be improved.
1. A method for manufacturing a semiconductor device, comprising:
forming a damascene insulating layer above a silicon substrate, the damascene insulating layer having a contact hole;
forming a barrier metal layer by sequentially forming a first ruthenium layer, a ruthenium oxide layer, and a second ruthenium layer in the contact hole of the damascene insulating layer; and
forming a copper line layer including a Cu—Ag—Au solid solution to fill the contact hole.
2. A method as defined in claim 1 , further comprising
forming a seed copper layer on the barrier metal layer in the contact hole, wherein the copper line layer is formed on the seed copper layer.
3. A method as defined in claim 1 , wherein the first ruthenium layer, the ruthenium oxide layer, and the second ruthenium layer are respectively formed at a thickness of about 10-500 Å.
4. A method as defined in claim 1 , wherein the ruthenium oxide layer is formed by exposing the first ruthenium layer under nitrogen oxide plasma or oxygen plasma.
5. A method as defined in claim 1 , wherein the Cu—Ag—Au solid solution includes AG and AU, and the Ag and Au are respectively contained in the copper line layer made of the Cu—Ag—Au solid solution at less than 5 weight %.
6. A method as defined in claim 1 , wherein:
the first ruthenium layer, the ruthenium oxide layer, and the second ruthenium layer are respectively formed at a thickness of about 10-500 Å;
the ruthenium oxide layer is formed by exposing the first ruthenium layer under nitrogen oxide plasma or oxygen plasma; and
the Cu—Ag—Au solid solution includes AG and AU, and the Ag and Au are respectively contained in the copper line layer made of the Cu—Ag—Au solid solution at less than 5 weight %.