By MARK LAPEDUS
Chipmakers continue to scale the transistor at advanced nodes, but they are struggling to maintain the same pace with the other two critical parts of the device—the contacts and interconnects.
That’s beginning to change, however. In fact, at 10nm/7nm, chipmakers are introducing new topologies and materials such as cobalt, which promises to boost the performance and reduce unwanted resistance in chips. It’s still too early to say if the changes will work. Early reviews are mixed.
To be sure, though, there is an inflection point taking place in leading-edge chips, which consist of three parts—the transistor, contacts and interconnects. The transistor resides on the bottom of the structure and serves as a switch. The interconnects, which reside on the top of the transistor, consist of tiny copper wiring schemes that transfer electrical signals from one transistor to another.