Power Semiconductor Module Cooler Layout With Welded Cooling Channel

The patent merges the sealing function and mechanical connection function into a single integrated sealing ring component made of elastomeric material. This sealing ring simultaneously provides the seal between the power semiconductor module and cooler, and acts as the mechanical fastener replacing traditional screws and O-rings, thereby reducing component count and eliminating O-ring aging issues.

The elastomeric sealing ring serves multiple functions: it provides thermal coupling between the module and cooler, creates a fluid-tight seal, and mechanically fastens the assembly together. This multi-functional component eliminates the need for separate O-rings, screws, and thermal interface materials.

The patent performs the laser welding of the cooling structure to the substrate before encapsulating the module in mold compound. By completing the welding operation prior to molding, the process ensures precise thermal coupling is established before the module is sealed, and allows control of welding parameters to avoid excessive heat that could damage subsequent molding materials.

The patent controls the laser welding parameters (power, duration, focal point) to limit the thermal input to the substrate and surrounding materials. By optimizing these parameters, the process achieves reliable welding of the cooling structure while keeping the peak temperature below the degradation threshold of the mold compound during subsequent encapsulation.

The patent separates the bonding process into two distinct stages: first, wire bonding is performed on the substrate under normal conditions to create electrical connections; second, the entire assembly (substrate with wire bonds and mounted components) is subjected to sintering pressure to bond the substrate to the cooler. This segmentation allows wire bonding to be completed before the high-pressure sintering step, avoiding wire bond destruction.

The patent performs wire bonding and component mounting on the substrate before applying sintering pressure. By completing the delicate wire bonding operation in advance, the subsequent sintering process only needs to bond the substrate to the cooler, and the wire bonds are already in place and protected during this final bonding step.