Patent ID: 7179753

Claim:
A method of manufacturing semiconductor devices, comprising: forming an insulating layer over a semiconductor substrate; forming contact holes in the insulating layer; forming a conductive layer over the insulating layer to bury the contact holes; rotating the semiconductor substrate; and etching the conductive layer by supplying an etching composition on the rotating semiconductor substrate without performing a polishing step prior to said etching, wherein the etching composition comprises a mixture of at least one oxidant selected from the group consisting of S 2 O 8 − and HNO 3 , at least one enhancer selected from the group consisting of HF, H 3 PO 4 , H 2 SO 4 , and HCl, and a buffer solution, and wherein the oxidant, the enhancer, and the buffer solution have a mixing ratio such that after the etching, the material of the conductive layer is only present inside the contact hole and does not remain over the insulating layer.