A study of the interfacial layer of Al and Al(1% Si)Si contacts using a zero-layer ellipsometry model

In this work, the interfacial layer of the AlSi and Al(1% Si)Si contacting system annealed at different temperatures have been studied using ellipsometry incorporated with a zero-layer model. The results show that the thickness of the interfacial P⁺ layer between Al or Al(1% Si) and the Si-substrate increases with the annealing temperature and the thickness of the P⁺-layer of the Al(1% Si)Si system is generally lower than that of the AlSi system. Also, the fraction of Al in the interfacial layer decreases with the annealing temperature for the AlSi system, but increases for the Al(1% Si)Si system. The electrical measurements show that the interface of the Al(1% Si)Si contact is more stable than that of the AlSi contact.