Abstract: The present invention relates to integrated circuits comprising a protective overcoat and thick copper connectors. According to one aspect of the inventions, vias in the protective overcoat are substantially filled with tungsten plugs, or plugs of another metal with a relatively low coefficient of thermal expansion. According to another aspect of the invention, large vias in the protective overcoat are replaced with arrays of smaller vias. The invention reduces the likelihood of device failures during temperature cycling tests. Also, the invention allows for smaller vias in the protective overcoat and removal of interconnect functions to the thick copper layer.

Abstract: In one embodiment of the present invention, a contact structure of a semiconductor device within an integrated circuit includes an active region, the active region having been defined using a mask provided on a substrate. The contact structure further includes an isolation region adjacent the active region and including a field oxide: the field oxide having been grown by exposure of the substrate to a thermal process and an oxygen-containing gas; a film having been formed on a top surface of the mask during exposure to the thermal process and oxygen-containing gas; a dry etching process having been performed to substantially remove the film from the top surface of the mask and to remove a top portion of the field oxide in the isolation region; and a wet etching process having been performed to substantially remove any portion of the mask remaining after the dry etching process.

Abstract: In one embodiment of the present invention, a contact structure of a semiconductor device within an integrated circuit includes an active region, the active region having been defined using a mask provided on a substrate. The contact structure further includes an isolation region adjacent the active region and including a field oxide: the field oxide having been grown by exposure of the substrate to a thermal process and an oxygen-containing gas; a film having been formed on a top surface of the mask during exposure to the thermal process and oxygen-containing gas; a dry etching process having been performed to substantially remove the film from the top surface of the mask and to remove a top portion of the field oxide in the isolation region; and a wet etching process having been performed to substantially remove any portion of the mask remaining after the dry etching process.

Abstract: A nitride wet etch in which liquid TEOS is flowed directly into the hot phosphoric acid bath before wafer etching begins. This preloads the bath chemistry with silicate ions, and thus helps assure very high selectivity to silicon oxides.

Abstract: A method is given for removing excess oxide from active areas after shallow trench isolation, without the use of chemical-mechanical polishing. A nitride mask protects active areas during the etch of isolation trenches. The trenches are filled with oxide, using high density plasma deposition, which simultaneously etches, providing a sloping contour around the isolation trenches. A further layer of nitride is used to provide a cap over the trench which seals to the underlying layer of nitride. The cap layer of nitride receives a patterned etch to remove the cap only over the active areas. This allows a selective etch to remove the excess oxide, which can be followed by a selective etch to remove the nitride layers.

Abstract: There is provided a filter medium comprising a microporous polyvinylidene fluoride membrane and a polymer containing a positively charged organic phosphonium compound grafted to the membrane in a concentration sufficient to provide a surface of said membrane with a positive charge such that there is minimal susceptibility to the extraction of said polymer. The polymer may also contain an acrylate or methacrylate. There is also provided a method for ultrapurifying a liquid and an ultrapurifying system for water.