| 摘要 |
PURPOSE: A method for controlling chemical-mechanical polishing time(CMP) is provided to exactly control the CMP time of a lot to be machined at next time by using a function equation from which a CMP characteristic varying on the CMP process can be predicted. CONSTITUTION: A method for controlling chemical-mechanical polishing time(CMP) extracts a function equation between the amount Y of a CMP removed for the CMP time X. From a graph drawn by the extracted function equation, the first degree function equation such as Y="AX"+B(B is a constant of Y axis intercept) for a period in which the amount of CMP removed has a linear relation against the CMP time X is then defined and the intercept value B is obtained from the first degree function equation. The CMP time X1 applied to the previous lot by a CMP process equipment and the thickness Y1 of the film removed as a result of the CMP are measured. The rate of CMP removal A1 for the previous lot is calculated by substituting the CMP time X1, the thickness X1 and the intercept value B for the first degree function equation. A CMP time X2 of a current lot is calculated by substituting the difference Y1-Y2 between the thickness Y1 of the film removed from the previous lot and the thickness Y2 of a film to be removed of a current lot, the rate of CMP removed A1 and the intercept value B, for the first degree function equation. The current lot is processed by CMP process by setting the value X1+X2 in which the calculated CMP time X2 is added to the CMP time X1 as a running time of the CMP process equipment.
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