Flip chip MCM-L using known good die

Flip chip MCM technologies have been in development for several years. Recent availability of SRAM known good die (KGD) has enabled the feasibility of memory-based MCMs. High performance memory devices rely on burn-in and speed sorting. Yield projections, especially of new designs utilizing advanced technologies, rendered four-chip MCMs infeasible. With the KGD process, bare die are available fully burned-in and tested, thus allowing MCM assembly in parity with module assemblies based on packaged parts. Motorola has combined these technologies to prototype a 16 Mbyte BurstRAM/sup TM/ module with KGD. The four die MCM has a four layer laminate substrate with eutectic solder clad bond pads. The die have a high lead evaporated bump, and go through a known good die process with a prescribed burn-in. The paper outlines customer applications, the assembly process, and product and process reliability requirements.