Monte Carlo Statistical Tolerance Analysis of a Parallel-Plate Multichip Power Module

A Monte Carlo statistical tolerance analysis is conducted on a parallel-plate, wirebond-less multichip power module (MCPM) to analyze the planarity across modules with post interconnects and identify which parts in the assembly contribute the most variation. Power electronics packaging has migrated from wirebonds to post interconnects that allow for vertical, parallel-plate modules, improving power density, reducing power loop inductances, and enabling double-sided cooled modules. Demonstrations of MCPMs of this structure have been limited in the number of die. This is a substantial gap in literature since as the number of die in parallel increases, the number of post interconnects and bondlines scale, resulting in more variation across component heights and reducing the yield and probability of connecting every interconnect. Different tolerance analyses are discussed and analyzed for the assembly of the MCPM, and a Monte Carlo statistical tolerance analysis is conducted to quantify the maximum height mismatch across the module and identify, which components introduce the most variation. Three MCPMs are fabricated using the statistical tolerance analysis, targeting components to reduce the maximum height mismatch. The 13 kV, six-die module is successfully characterized and is the first functional module of its kind.