Control of chemical mechanical polishing pad conditioner directional velocity to improve pad life

A method of developing a pad wear and pad conditioning model for optimization of the pad conditioning for polishing pads used to remove material from a wafer, comprising the steps of:

• a) determining the relationship between at least one pad conditioning parameter and wafer material removal rate;
• and
• b) determining maximum and minimum values for each of the at least one pad conditioning parameters and the wafer material removal rate;
• and
• c) recording the relationships and minimum and maximum values of the at least one pad conditioning parameter and the wafer removal rate.

A method of conditioning a planarizing surface in a chemical mechanical polishing (CMP) apparatus having a polishing pad against which a wafer is positioned for removal of material therefrom and a conditioning disk is positioned for conditioning of the polishing pad, comprising the steps of:

• (a) developing a pad wear and pad conditioning model that defines wafer material removal rate as a function of pad conditioning parameters by:
• (i) determining the relationship between at least one pad conditioning parameter and wafer material removal rate;
• and
• (ii) determining maximum and minimum values for each of the at least one pad conditioning parameters and the wafer material removal rate;
• and
• (iii) recording the relationships and minimum and maximum values of the at least one pad conditioning parameter and the wafer removal rate;
• (b) polishing a wafer in the CMP apparatus under a first set of pad conditioning parameters including conditioning disk rotational speed and direction, selected to maintain wafer material removal rates within preselected minimum and maximum removal rates;
• (c) determining a wafer material removal rate occurring during said polishing step;
• and
• (d) calculating updated pad conditioning parameters based upon said determined wafer material removal rate of said step (b) and the pad wear and conditioning model to maintain wafer material removal rates within the maximum and minimum removal rates.

A method of conditioning a planarizing surface in a chemical mechanical polishing (CMP) apparatus having a polishing pad against which a wafer is positioned for removal of material therefrom and a conditioning disk is positioned for conditioning of the polishing pad, comprising the steps of:

• a) providing a pad wear and conditioning model that defines wafer material removal rate as a function of at least one pad conditioning parameter and that identifies a maximum and minimum value for each of the at least one pad conditioning parameter and the wafer removal rate;
• b) polishing a wafer in the CMP apparatus under a first set of pad conditioning parameters selected to maintain wafer material removal rates within preselected minimum and maximum removal rates;
• c) determining a wafer material removal rate occurring during said polishing step;
• d) calculating updated pad conditioning parameters based upon said determined wafer material removal rate of said step (c) and the pad wear and conditioning model of said step (a) and
• e) conditioning the polishing pad using the updated conditioning parameters.