Abstract: A method includes depositing a plurality of layers on a substrate, patterning a first mask overlying the plurality of layers, and performing a first etching process on the plurality of layers using the first mask. The method also includes forming a polymer material along sidewalls of the first mask and sidewalls of the plurality of layers, and removing the polymer material. The method also includes performing a second etching process on the plurality of layers using the remaining first mask, where after the second etching process terminates a combined sidewall profile of the plurality of layers comprises a first portion and a second portion, and a first angle of the first portion and a second angle of the second portion are different to each other.

Abstract: 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.