B. Yoo, S. Kondo, S. Tokitoh, A. Namiki, K. Misawa, K. Inukai, N. Ohashi, N. Kobayashi
{"title":"Characterization of patterned low-k film delamination during CMP for the 32nm node Cu/ultra low-k (k=1.6-1.8) integration","authors":"B. Yoo, S. Kondo, S. Tokitoh, A. Namiki, K. Misawa, K. Inukai, N. Ohashi, N. Kobayashi","doi":"10.1109/IITC.2004.1345761","DOIUrl":null,"url":null,"abstract":"Pattern dependence of ultra low-k (ULK, k=1.6-1.8) film delamination during Cu-CMP has been investigated to integrate the 32 nm node Cu/ULK damascene interconnects. A CMP mask that has various kinds of dummy-patterns was developed for quantitative characterization of the ULK film delamination. As a result, the perimeter of the pattern, which is the length along the boundary between Cu and low-k film, was found to be a determinative parameter in delamination of the patterned low-k film rather than pattern density. This is because Cu interconnects with higher-density perimeter increase the tolerance to shear stress generated by the CMP, and thus prevent the delamination due to the low mechanical strength of the ULK film (modulus; E<2GPa). A soft pad polishing was also effective in suppressing the mechanical damage. On the basis of these results, Cu damascene interconnects with ULK film were successfully integrated on 300mm wafers.","PeriodicalId":148010,"journal":{"name":"Proceedings of the IEEE 2004 International Interconnect Technology Conference (IEEE Cat. No.04TH8729)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2004-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"6","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the IEEE 2004 International Interconnect Technology Conference (IEEE Cat. No.04TH8729)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/IITC.2004.1345761","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 6
Abstract
Pattern dependence of ultra low-k (ULK, k=1.6-1.8) film delamination during Cu-CMP has been investigated to integrate the 32 nm node Cu/ULK damascene interconnects. A CMP mask that has various kinds of dummy-patterns was developed for quantitative characterization of the ULK film delamination. As a result, the perimeter of the pattern, which is the length along the boundary between Cu and low-k film, was found to be a determinative parameter in delamination of the patterned low-k film rather than pattern density. This is because Cu interconnects with higher-density perimeter increase the tolerance to shear stress generated by the CMP, and thus prevent the delamination due to the low mechanical strength of the ULK film (modulus; E<2GPa). A soft pad polishing was also effective in suppressing the mechanical damage. On the basis of these results, Cu damascene interconnects with ULK film were successfully integrated on 300mm wafers.