Patent ID: 7333875

Claim:
A method of transferring chemical mechanical polishing (CMP) processes in a CMP process tool comprising the steps of: a. performing a first CMP process by a CMP process tool, polishing at least one control wafer to obtain a measured removal rate; and b. performing a second CMP process different from the first CMP process, performance of which comprises: multiplying the measured removal rate by a conversion factor to obtain a predicted removal rate; applying the predicted removal rate to the CMP process tool in order to determine a required polishing time; and completing the second CMP process; wherein the conversion factor is obtained by the steps of: a. choosing a control parameter from control parameters of the first CMP process as a variable and keeping other control parameters of the control parameters fixed, varying values of the variable and polishing the at least one control wafer to obtain a correlative expression between the variable and a removed thickness of the at least one control wafer; b. choosing another control parameter of the first CMP process as a new variable and repeating step (a) until individual correlative expressions between each of the control parameters and a removed thickness of the at least one control wafer are obtained; c. multiplying the correlative expressions to obtain a work function; d. providing the second CMP process having the same types of control parameters as the first CMP process; e. respectively applying a plurality of known values of the first CMP process and the second CMP process to the work function to obtain a first result and a second result respectively; and f. dividing the second result by the first result to obtain the conversion factor.