Semiconductor Electrode Nitride Barrier Against Solder Infiltration

An intermediate layer is introduced between the organic protective film and the aluminum electrode. This intermediate layer acts as a barrier that prevents solder infiltration to the aluminum electrode while maintaining the overall structure. The intermediate layer is positioned at the triple point region where the protective film, plated layer, and emitter electrode meet, blocking the infiltration path of solder without requiring fundamental changes to the existing layered structure.

The intermediate layer serves as a buffer and barrier layer between the protective film and the aluminum electrode. Even when the protective film and plated layer overlap during manufacturing variations, the intermediate layer prevents solder from reaching the aluminum electrode. This relaxes the manufacturing precision requirements by providing a tolerance buffer zone that accommodates alignment variations without compromising reliability.

The protective film structure is segmented into multiple functional layers: the organic protective film layer and an additional intermediate layer. This segmentation allows each layer to perform its specific function - the protective film provides general protection while the intermediate layer specifically blocks solder infiltration paths. The segmentation approach prevents solder infiltration by creating a multi-barrier structure without requiring complete redesign of the device architecture.

The intermediate layer is strategically positioned at the triple point where the protective film, plated layer, and emitter electrode converge. This intermediate layer eliminates the exposed triple point structure that is prone to crack initiation and propagation. By filling and blocking this vulnerable region, the intermediate layer prevents crack progression while maintaining compatibility with existing manufacturing processes, as it can be deposited using standard thin-film techniques.