Reducing contact resistance of sidewall interconnect in 3D electronic package by breakdown method
Due to the process issues,3D package structures with sidewall interconnect inevitably produce a copper oxide layer on the surface of the sidewall redistribution stubs,which results in higher contact resistance at the interconnect interface. The samples processed under different pre-treatment conditions were analyzed using the breakdown method. The interconnect interface of the samples after breakdown was characterized by X-ray spectroscopy,selected area electron diffraction,and high-resolution transmission microscopy. The results show that the breakdown method can achieve a resistance reduction effect of over 95％ for the samples prepared under different baking environments,baking time,and cleaning processes. Additionally,the contact resistance is reduced to below 1 Ω in all cases. The contact resistance of the sample,prepared by vacuum baking,baking for 10 hours,and plasma treatment,reaches a minimum of 0.26 Ω after the breakdown treatment. With the breakdown method,the contact resistance of the interconnect interface is reduced by applying an electric field to the copper oxide layer. As a result,the copper ions migrates along the direction of the electric field and is reduced to polycrystalline Cu and Cu2O,forming a low-resistance conductive path. It is shown that the breakdown method is suitable for reducing the contact resistance of the interconnect interface in the sidewall interconnect process.
3D packagesidewall interconnectinterconnect interfacecopper oxide filmcontact resistancebreakdown
万方数据
维普
