Taiwan Semiconductor Manufacturing Comp. Ltd.

Chen-Hwa Yu

Syun-Ming Jang Jang

Tze-Liang Lee

Fan-Keng Yang

A method for planarizing an oxide surface and removing dishing or erosion defect from a semiconductor wafer. An apparatus for carrying out the planarization process on a semiconductor wafer is further described. In the method, a wafer that has metal residues or dishing or erosion defect after a copper CMP process is first rotated at a rotational speed of at least 1000 RPM, while simultaneously a solvent/abrasive particles mixture is injected onto the rotating surface for a sufficient length of time until the metal residues, the dishing or erosion defect is removed. The rotational speed of the semiconductor wafer can be suitably controlled in a range between about 1000 RPM and about 10,000 RPM. For the removal of an oxide layer, a suitable solvent of diluted HF and a suitable abrasive particle such as aluminum oxide may be used.

Headless CMP process for oxide planarization

A new method of forming sub-micron features, such as a gate feature in particular, of less than 0.25 micrometers (.mu.m) to 0.18 .mu.m employing a micro-patterning process is disclosed. It is shown that the critical dimension width of a polysilicon gate can be controlled precisely by using very thin lithographic layers in a micro-patterning process. This is accomplished by forming a conductive layer over a gate oxide layer, followed by forming a planarization layer, an anti-reflective coating (ARC), and then, as a key feature, a very thin photoresist layer. A high resolution photoresist mask is next formed without the presence of any reflections in the photoresist layer due to the high optical absorptivity of the ARC, or BARC, at the bottom of the photoresist layer. Then, the precisely formed pattern is successively transferred, by etching, to BARC and to planarization layers which in turn form as second and first hard masks, respectively. In a first embodiment, the thin photoresist layer along with the BARC layer are removed simultaneously with the forming of the gate electrode in the conductive layer. In the second embodiment, the photoresist mask as well as the second hard mask are removed simultaneously with the forming of the gate electrode in the conductive layer.

Growing community of inventors

Hsin-Chu, Taiwan

Chen-Hwa Yu