TY - JOUR N2 - Accurate flatness measurement of silicon wafers is affected greatly by the gravity-induced deflection (GID) of the wafers, especially for large and thin wafers. The three-point-support method is a preferred method for the measurement, in which the GID uniquely determined by the positions of the supports could be calculated and subtracted. The accurate calculation of GID is affected by the initial stress of the wafer and the positioning errors of the supports. In this paper, a finite element model (FEM) including the effect of initial stress was developed to calculate GID. The influence of the initial stress of the wafer on GID calculation was investigated and verified by experiment. A systematic study of the effects of positioning errors of the support ball and the wafer on GID calculation was conducted. The results showed that the effect of the initial stress could not be neglected for ground wafers. The wafer positioning error and the circumferential error of the support were the most influential factors while the effect of the vertical positioning error was negligible in GID calculation. L1 - http://www.czasopisma.pan.pl/Content/90361/mainfile.pdf L2 - http://www.czasopisma.pan.pl/Content/90361 PY - 2015 IS - No 4 EP - 546 KW - flatness measurement KW - large and thin silicon wafer KW - GID KW - three-point-support method KW - initial stress A1 - Liu, Haijun A1 - Dong, Zhigang A1 - Kang, Renke A1 - Zhou, Ping A1 - Gao, Shang PB - Polish Academy of Sciences Committee on Metrology and Scientific Instrumentation VL - vol. 22 DA - 2015[2015.01.01 AD - 2015.12.31 AD] T1 - Analysis Of Factors Affecting Gravity-Induced Deflection For Large And Thin Wafers In Flatness Measurement Using Three-Point-Support Method SP - 531 UR - http://www.czasopisma.pan.pl/dlibra/publication/edition/90361 T2 - Metrology and Measurement Systems ER -