While Intel's will adopt cobalt for the bottom two layers of its 10nm interconnects, EE Times has a new story that offers further evidence that copper will likely remain the interconnect of choice. For many years, it was believed that alternative materials would be needed at smaller process nodes but last month IBM gave a presentation that copper would remain suitable for 5nm and below.
Now there's news from Aveni that they've discovered that alkaline-based processing chemistries could extend copper to the 3nm node, and possibly even to the end of the road for CMOS technology.
Aveni claims its back-end-of-line alkaline electroplating chemistry makes a switch from copper unnecessary because it leaves the cobalt layer untouched. “One of the problems with acidic chemistries is that they often etch through to the underlying barrier layer. With alkaline chemistry, you do not have this underlay-etching problem,” Aveni CTO Frédéric Raynal told EE Times in an advance interview.