Papers by Keyword: Pad Conditioning

Abstract: The primary consumables in chemical mechanical polishing (CMP) are the polishing pad and the slurry. The polishing pad significantly influences the stability of the polishing process and the cost of consumables (CoC). During the polishing process, a diamond dresser must be frequently employed to remove the debris to prevent accumulation, a process known as pad conditioning. In this paper, we investigated the physical properties of the CMP pad such as compressibility, thickness, and surface roughness. The difference between new and used pads has been studied. Conclusively, conditioning via a diamond dresser will extend pad life and reduce CoC.

Abstract: This paper studied the effects of the off-process conditioning parameters on the pad performances. The pad conditioning was evaluated based on the measurement of pad removal rate, the observation of the conditioned pad surface. The performances of conditioned pads were evaluated also by the material removal rate (MRR) and the surface roughness of polished wafers in the CMP experiments of LiTaO3 crystal wafers.

Abstract: Polishing pad plays a key role in determining polish rate and planarity of a chemical mechanical planarization (CMP). The properties of the pad would deteriorate during polishing because of pad surface grazing, which results in reduced removal rates and poorer planarity of wafer surface. Pad conditioning and its influence on pad surface structure and CMP process is introduced and discussed in this paper. The study shows that the surface structure can be regenerated by breaking up the glazed areas with conditioner, MRR(Material Removal Rate) can be maintained at high level with proper pad conditioning, and UN(Non-uniformity)can also improved. Orthogonal experiments design is employed in this study to determine the best conditioning parameters.

Abstract: Indium tin oxide (ITO) CMP was performed by change of de-ionized water (DIW) temperature in pad conditioning process. DIW with high temperature was employed in pad conditioning immediately before ITO-CMP. The removal rate of ITO thin film polished by silica slurry immediately after pad conditioning process with the different DIW temperatures dramatically increased to 93.0 nm/min after pad conditioning at DIW of 75 oC, while that after the general conditioning process at 30 oC was about 66.1 nm/min. The grains of ITO thin film became indistinguishable by CMP after pad conditioning with the high-temperature DIW. The carrier density decreased with the increase of conditioning temperature. The hall mobility rapidly increased regardless of conditioning temperature. The uniformity of optical transmittance also improved.