Abstract: The invention provides a method of manufacturing a metal interconnect. A substrate having a metal line formed thereon is provided. An anti-reflection layer is formed on the metal line. A dielectric layer with a relatively low dielectric constant is formed over the substrate. A patterned photoresist layer is formed on the dielectric layer. The patterned photoresist layer has an opening exposing a portion of the dielectric layer. The portion of the dielectric layer exposed by the opening is removed to form a via hole. The patterned photoresist layer is removed by an O.sub.2 --H.sub.2 O--CF.sub.4 plasma. The pressure of the O.sub.2 --H.sub.2 O--CF.sub.4 plasma is about 800-1000 torr. A cleaning process is performed by a post-stripper rinse solution and de-ionized water without using an acetone solution. A barrier layer is formed over the substrate by chemical vapor deposition. A metal nucleation is performed for a long time by chemical vapor deposition to form metal nuclei on the barrier layer.

Abstract: A method for fabricating a via that uses a hard etching mask for etching the via. A photoresist layer used to pattern the hard etching mask is removed before starting the via etching. The hard etching mask includes a TiN etching mask, a silicon nitride etching mask, and a oxide/TiN etching mask. For each different etching mass, the TiN etching mask is not necessarily removed after etching; the silicon nitride etching mask is removed after etching; the oxide layer in the oxide/TiN etching mask is sacrificial layer.

Abstract: A method of forming a via is provided comprising a plasma treatment at the spin-on-glass layer after forming the unlanding via. The plasma comprises hydrogen and a second gas. The mist containing in the spin-on-glass layer is damaged and removed away.

Abstract: A method of forming a contact via includes forming a wiring, a first insulator layer, and a spin-on glass layer, respectively, over a semiconductor substrate. Fluorine ions are implanted into the spin-on glass layer. A second insulator layer is formed over the spin-on glass layer. The wiring is exposed by patterning the second insulator layer, the spin-on glass layer, and the first insulator layer, respectively.