Abstract: A method for etching vias having sloped sidewalls is provided, wherein the vias are formed in an interlayer dielectric formed on top of an interconnect layer using a patterned photoresist film as a mask. A top portion of the via is formed with a wet etch process which isotropically undercuts the masking film thereby creating a sloped sidewall. A bottom portion of the via is formed by a dry etch process comprising the steps of alternating between a number of isotropic mask erosion steps and a number of anisotropic dielectric etch steps, so that the interlayer dielectric exposed to the anisotropic etch by the mask opening is enlarged with each mask erosion step. Thus, a slope is created on the dry etched portion of the via sidewall as well as the wet etched portion of the via sidewall.

Abstract: A process described provides a sloped contact etch. The process has the steps of: etching a substrate then removing the polymer that is produced during the substrate etch. These two steps are alternated until a desired depth is reached. Next, the resist is etched followed by an etch of the substrate. This is then repeated until the required depth is reached. By varying the duration and repetition of the etches, the slope of the etch can be regulated.