Effect of temperature on pad surface contact area in chemical mechanical planarization

In this study, pad surface contact area measurement was performed using laser confocal microscopy at elevated temperatures under dry and static condition to illustrate the effect of temperature on the mechanical contacts in chemical mechanical planarization. Pad surface contact area and contact density were measured for a Cabot Microelectronics Corporation D100 pad sample at 27.6 kPa with a custom-made sample holder that was designed to heat the pad sample during the measurement. When the pad surface temperature increased from 25 to 45°d asperities became much softer and resulted in a significant increase (from 0.029% to 0.092%) in the pad contact area percentage while the contact density remained in the same range.