Patent attributes
A method of forming an integrated circuit structure includes forming a patterned passivation layer over a metal pad, with a top surface of the metal pad revealed through a first opening in the patterned passivation layer, and applying a polymer layer over the patterned passivation layer. The polymer layer is substantially free from N-Methyl-2-pyrrolidone (NMP), and comprises aliphatic amide as a solvent. The method further includes performing a light-exposure process on the polymer layer, performing a development process on the polymer layer to form a second opening in the polymer layer, wherein the top surface of the metal pad is revealed to the second opening, baking the polymer, and forming a conductive region having a via portion extending into the second opening.