Cu/diamond Composite Electrodes for Low Thermal Resistance Packaging in High-Power IGCTs

This study demonstrates the superior thermal management capabilities of Cu/diamond composite electrodes in 6-inch press-pack insulated gate commutated thyristors (IGCTs). Through systematic material characterization and device-level validation, the Cu/diamond composite exhibited an exceptional thermal conductivity of 580-680 W/(m•K) and a low coefficient of thermal expansion (<6×10⁻<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> K<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup>). Experimental results from a thermal resistance test platform revealed a 39.2% reduction in junction-to-case thermal resistance (1.24 K/kW improvement) compared to conventional edge-gate IGCTs, enabling a rated current capacity of 4246 A with 20% design margin. The high surface flatness achieved by a thin Mo-Cu coating further facilitated reliable interfacial contact without compromising the intrinsic thermal advantages of the Cu/diamond matrix.