| 摘要 |
PROBLEM TO BE SOLVED: To flatten a semi-conductor wafer and other work piece by periodically applying the downward or upward force to any one of a wafer pushed to a polishing pad or the polishing pad during the flattening. SOLUTION: Downward or upward force is periodically applied to a wafer or a pad 13. In the case where the force is applied to the pad 13 and the periodical force is interrelated with the relaxing time of the pad, a chemical and mechanical flattening process is remarkably improved. During the operation of the chemical and mechanical flattening process in the normal condition, the periodical force and the compressibility of the pad 13 are interrelated with each other so that a height of the pad 13 is maintained between a compression height 13b expressed with dotted lines 13d, 13e and a compression released height 13c. Height of the pad 13 between the dotted lines 13d, 13e is defined as Hop. Height of the pad 13 is higher than the compression height 13b, and lower than the compression released height 13c. Chemical and mechanical flattening process is remarkably improved by operating this process within a range Hop of the operation height of the pad 13, and an improved result of flattening can be obtained. |
