A new mechanism for degradation of Al-Si-Cu/TiN/Ti contacted p-n junction

A new degradation mechanism that involves time dependent p-n junction characteristics is described. It has been found that reverse bias leakage current of the p-n junctions increases during reverse bias and temperature aging stress. It it clarified that this p-n junction degradation is dependent on crystallinity of the Ti-Si interdiffused layer at the contact interface in the Al-Si-Cu/TiN/Ti/Si substrate structure. In the case of an amorphous Ti-Si layer, the degradation is caused by diffusion of positively ionized Ti enhanced by the applied electric field.< >