Mechanism for manufacturing semiconductor device

A method for manufacturing a semiconductor device, the method comprising:

• forming a gate electrode over a substrate;
• forming a hard mask over the gate electrode, wherein the hard mask comprises a metal oxide;
• forming an interlayer dielectric (ILD) layer over the hard mask;
• forming a contact hole in the ILD layer, wherein the contact hole exposes a source/drain;
• filling the contact hole with a conductive material;
• and
• applying a chemical mechanical polish process to the ILD layer and the conductive material, wherein the chemical mechanical polish process stops at the hard mask, the chemical mechanical polish process uses a slurry containing a boric acid or its derivative, the chemical mechanical polish process has a first removal rate of the conductive material and a second removal rate of the hard mask, and a ratio of the first removal rate of the conductive material to the second removal rate of the hard mask is greater than about 5.

A method for manufacturing a semiconductor device, the method comprising:

• forming a gate electrode over a substrate;
• forming a hard mask over the gate electrode;
• forming an interlayer dielectric (ILD) layer over the hard mask;
• forming a contact hole in the ILD layer, wherein the contact hole exposes a source/drain;
• filling the contact hole with a conductive material;
• and
• applying a chemical mechanical polish process to the ILD layer and the conductive material, wherein the chemical mechanical polish process stops at the hard mask, the chemical mechanical polish process uses a slurry containing a boric acid or its derivative, the hard mask has a first thickness prior to the chemical mechanical polish process and a second thickness after the chemical mechanical polish process, and a ratio of the first thickness to the second thickness is less than about 1.8.