Abstract: A method is provided for forming contact via in an integrated circuit. Initially, a first buffer layer is formed over an insulating layer in an integrated circuit. The first buffer layer has a different etch rate from the insulating layer. A second buffer layer is then formed over the first buffer layer, with the second buffer layer having an etch rate which is faster than the first buffer layer. An isotropic etch is performed to create an opening through the second buffer layer and a portion of the first buffer layer. Because the second buffer layer etches faster than the first buffer layer, the slant of the sideswalls of the opening can be controlled. An anisotropic etch is then performed to complete formation of the contact via.

Abstract: An interconnect structure, and method for forming same, is suitable for use in integrated circuits such as SRAM devices. The structure uses masking of a polycrystalline silicon interconnect level to move a P-N junction to a region within a polycrystalline silicon interconnect line, rather than at the substrate. This P-N junction can then be shorted out using a refractory metal silicide formed on the polycrystalline silicon interconnect structure.