High Performance Cu Containing Ru or RuNx for Barrierless Metallization

This article reports novel copper seed layers containing dilute Ru or RuN
x
for the barrierless metallization. Based on XRD, FIB, TEM, resistivity and leakage current measurement results, we conclude that copper does not react with Si up to 680°C for 1 hour when the Ru-or RuN
x
-bearing seed layer is directly in contact with the barrier-free Si. Our results shed lights on the possibility of using these layers in the barrierless metallization process.