| Currently, Chemical Mechanical Polishing (CMP) is the most effective technology to obtain the ultra smooth and damage free surface of wafer and the only way to achieve the local and global planarization of wafer. Polishing pad is the main consumables of the CMP. The surface texture and constituent of the pad directly affects its performances and even the CMP process.Grooving on the pad surface is an important way to improve its performances. The shape, size and distribution of grooves on the pad effect the flux and pressure distribution of slurry between wafer and pad in CMP. However, such studies as the forming process of groove on the pad and the role of groove in the CMP have been rarely reported. A new grooving method based laser engraving technology is presented in thesis. The grooves with various distributing shape such as homocentric circle, square and involute, are produced by use of the technology, and the effects of the shape, size and distribution of the grooves are investigated.Adding abrasive into pad, fixed abrasive pad, is also an effective method to improve the performances of the pad, the uniformity of the abrasive distribution between the pad and wafer can be improved by using fixed abrasive pad so as to reduce the material remove non-uniformity on wafer surface and increase the planarization rate. Furthermore, when abrasives desquamate from the pad surface in polishing, the pad maintains porous and rough surface, this reduce the times of conditioning pad and prolong the pad life. The measurement and evaluation methods of properties of the fixed abrasive pad, such as microstructure, hardness, density, compression ratio resilience rate, surface roughness and polishing fluid absorption capacity, are studied. Through contrastive experiments with the polishing pad without abrasive, the effects of the fixed abrasive pad in CMP are analyzed. Through grooving on the fixed abrasive pad, the performances of the pad are enhanced and improve markedly.
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