RELIABLE INTERCONNECTS

摘要

Semiconductor device and method for forming a semiconductor device are presented. The method includes providing a substrate prepared with intermediate dielectric layer having interconnect levels. The interconnect levels include M1 to MX metal levels, where 1 is the lowest level and X corresponds to a number of metal level. The metal level MX includes a metal pad having an oxidized portion. An upper level having an upper dielectric layer is formed over the dielectric layer having MX. The upper dielectric layer includes a plurality of via contacts over the metal pad and a metal line over the via contacts. The oxidized portion remains within the metal pad and prevents punch through between MX and its adjacent underlying metal level MX-1.

主权项

1. A method for forming a device comprising:
providing a substrate prepared with intermediate dielectric layer having interconnect levels, wherein the interconnect levels include M1 to MX metal levels, where 1 is the lowest level and X corresponds to a number of metal level, the metal level MX includes a metal pad having an oxidized portion; and forming an upper level having an upper dielectric layer over the dielectric layer having MX, wherein the upper dielectric layer is processed to form a plurality of via openings over the metal pad and a metal line trench over the via openings, wherein the metal line trench is formed by
providing a patterned mask layer having a pattern corresponding to the metal line trench,performing an etch to remove portions of the dielectric layer unprotected by the patterned mask,performing a removal process to remove the patterned mask layer, wherein the removal process does not remove the oxidized portion of the metal pad, thereby preventing punch through between MX and its adjacent underlying metal level MX-1.