Method for enhancing adhesion between layers in beol fabrication

Abstract

A novel method for enhancing interface adhesion between adjacent dielectric layers, particularly between an etch stop layer and an overlying dielectric layer having a low dielectric constant (k) in the formation of metal interconnects during the fabrication of integrated circuits on semiconductor wafer substrates. The method may include providing a substrate, providing an etch stop layer on the substrate, providing an oxygen-rich dielectric pre-layer on the etch stop layer and providing a major dielectric layer on the oxygen-rich dielectric pre-layer. Metal interconnects are then formed in the dielectric layers. The oxygen-rich dielectric pre-layer between the etch stop layer and the upper dielectric layer prevents or minimizes peeling and cracking of the layers induced by stresses that are caused by chemical mechanical planarization of metal layers and/or chip packaging.