Abstract: A method and apparatus for determining the presence of foreign material on a substrate chuck. The method includes: placing a bottom surface of a substrate on a top surface of the substrate chuck; applying a lateral force in a direction parallel to a top surface of the substrate chuck to the substrate; when the substrate moves partially off or moves completely off the substrate chuck in response to the applying the lateral force then a defect is present between the top surface of the substrate chuck and the bottom surface of the substrate; or when the substrate remains completely on the substrate chuck in response to the applying the lateral force then a defect is not present between the top surface of the substrate chuck and the bottom surface of the substrate.

Abstract: An apparatus and methods for measuring the clamping force applied to a substrate by clamping elements of a substrate holder. The apparatus include a pneumatic cylinder, a two position, three way valve and a pressure gauge. In a first position of the valve, the gauge and a bore of the cylinder are vented or pre-pressurized. In a second position of the valve, the bore and gauge are isolated. The methods include placing the apparatus with the valve in the first position between clamping elements set to a non-clamping position, moving the valve to the second position, setting the clamping elements to a clamping position and reading a pressure on the gauge.

Abstract: A method and apparatus for determining the presence of foreign material on a substrate chuck. The method includes: placing a bottom surface of a substrate on a top surface of the substrate chuck; applying a lateral force in a direction parallel to a top surface of the substrate chuck to the substrate; when the substrate moves partially off or moves completely off the substrate chuck in response to the applying the lateral force then a defect is present between the top surface of the substrate chuck and the bottom surface of the substrate; or when the substrate remains completely on the substrate chuck in response to the applying the lateral force then a defect is not present between the top surface of the substrate chuck and the bottom surface of the substrate.

Abstract: An apparatus and methods for measuring the clamping force applied to a substrate by clamping elements of a substrate holder. The apparatus include a pneumatic cylinder, a two position, three way valve and a pressure gauge. In a first position of the valve, the gauge and a bore of the cylinder are vented or pre-pressurized. In a second position of the valve, the bore and gauge are isolated. The methods include placing the apparatus with the valve in the first position between clamping elements set to a non-clamping position, moving the valve to the second position, setting the clamping elements to a clamping position and reading a pressure on the gauge.

Abstract: A calibration gauge, an apparatus and a method for calibrating sensors that detect wafer protrusion from a wafer cassette using the calibration gauge. The calibration gauge includes a disk having a first region which is a circular sector of central angle A1 having a constant radius R1 about a center and an integral second region of increasing radius about the center, the increasing radius increasing from R1 to R2 through a central angle A2, wherein R2 is greater than R1 and A1+A2 equals 360°.

Abstract: A calibration gauge, an apparatus and a method for calibrating sensors that detect wafer protrusion from a wafer cassette using the calibration gauge. The calibration gauge includes a disk having a first region which is a circular sector of central angle A1 having a constant radius R1 about a center and an integral second region of increasing radius about the center, the increasing radius increasing from R1 to R2 through a central angle A2, wherein R2 is greater than R1 and A1+A2 equals 360°.