Methods and apparatus provide for: a base on which a substrate may be releasably coupled; a moving belt located with respect to the base such that a contact surface thereof is operable to remove material from a top surface of the substrate; and a plurality of actuators, at least two of which are independently controllable, located with respect to the base and the moving belt such that a corresponding plurality of pressure zones are defined to provide pressure between the moving belt and the top surface of the substrate.