Advanced Method for Monitoring Copper Interconnect Process

Stabilizing the copper interconnect process is the key to improving yield and reliability. A stable process for forming adequate grains in a copper film is important, but there is no proper method for monitoring the grains in that film. We introduce the micro-haze method, an advanced method for monitoring grain size using scattering light. We experimentally verified the effectiveness of the method and concluded that the method enables the monitoring the grains in a copper film.