Method of chemical mechanical polishing aluminum containing metal layers and slurry for chemical mechanical polishing

A semiconductor processing method of chemical mechanical polishing an aluminum containing metal layer on a semiconductor substrate comprising the following steps:

• providing a chemical mechanical polishing slurry comprising H.sub.3 PO.sub.4 at from about 0.1% to about 20% by volume;
• H.sub.2 O.sub.2 at from about 1% to about 30% by volume;
• H.sub.2 O;
• and a solid abrasive material;
• applying the slurry onto an aluminum containing metal layer on a semiconductor substrate;
• polishing the aluminum containing metal layer having the applied slurry;
• reacting the aluminum of the metal layer with the H.sub.2 O.sub.2 of the slurry to form aluminum oxide;
• and
• chemically and mechanically removing aluminum oxide from the wafer with the slurry and polishing action.

A semiconductor processing method of chemical mechanical polishing a layer on a semiconductor substrate, the layer comprising titanium, the method comprising the following steps:

• providing a chemical mechanical polishing slurry comprising H.sub.3 PO.sub.4 at from about 0.1% to about 20% by volume;
• H.sub.2 O.sub.2 at from about 1% to about 30% by volume;
• H.sub.2 O;
• and a solid abrasive material;
• and
• chemical mechanical polishing a titanium containing layer on a semiconductor substrate with the slurry.

A method of processing a semiconductor wafer comprising the following steps:

• providing a barrier layer comprising titanium atop a semiconductor wafer;
• providing a metal layer comprising aluminum atop the barrier layer;
• providing a chemical mechanical polishing slurry comprising H.sub.3 PO.sub.4 at from about 0.1% to about 20% by volume;
• H.sub.2 O.sub.2 at from about 1% to about 30% by volume;
• H.sub.2 O;
• and a solid abrasive material;
• and
• chemical mechanical polishing the aluminum containing metal layer and barrier layer with the slurry in a single chemical mechanical polishing step.