A study of the total thickness variation in the grinding of ultra-precision substrates

A kinematic model of the grinding of ultra-precision substrate with a rotary-table vertical-spindle surface grinder is developed to calculate the scratch of a single grit traveling along the substrate. The surface integrity of the ground substrate may be greatly influenced by the grinding passes ratio from the center to the periphery of the substrate. The total thickness variation (TTV) of the ground substrate is influenced considerably by the value of the rotational speed ratio of the wheel and the worktable and the wheel infeed rate, while the inclination of the grinding wheel axis must be set appropriately to improve the TTV of the ground substrate.