Pad Roughness Effects

When MRR of oxide wafer polishing on porous ICIOOO pad and on nonporous NCP pad is compared, it shows that MRR on nonporous NCP pad is slightly lower than that on porous ICIOOO pad, and WTWNU of MRR is comparable for NCP and ICIOOO pads (see Fig. 5.4). The WIWNU of MRR on NCP pad is much lower than that on ICIOOO pad. This demonstrates better 

FIGURE 5.4 MRR variation from wafer to wafer (WTWNU) 100 oxide wafers polished on NCP pad (lower line with diamond marker) versus polished on ICIOOO pad (upper line with square marker). 

FIGURE 5.6 Comparison of patterned wafer profile and step height reduction efficiency (SHRE) for polishing on ICIOOO and NCP pads (a) Wafer profile before polishing, (b) wafer profile after polishing, (c) SHRE on ICIOOO pad, (d) SHRE on NCP pad. 

FIGURE 5.7 Comparison of normalized patterned wafer step height reduction efficiency (SHRE) for polishing on ICIOOO and various NCP pads. 

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