Bare die testing and MCM probing techniques

The author discusses two important issues regarding the development and manufacture of multichip modules (MCMs). First, a method is described which is used for testing bare chips at the full operating frequency and over temperature extremes. This approach utilizes a modified wafer probe system and a high-speed digital tester for at-speed performance characterization of individual chips prior to insertion into an MCM. The purpose is to fully assure that the device will perform as required once committed to the module. Second, a system is described for automated internal probing of functioning MCMs. Again, a standard wafer probe system is adapted for this purpose. This system permits characterization of fully populated MCMs