Patent ID: 7800761

Claim:
An interferometric-spatial-phase imaging (ISPI) system comprising: a substrate wafer; an alignment configuration permanently embedded in the backside of said substrate wafer including a first marking element having at least one constant period in two orthogonal directions, said alignment configuration forms a global coordinate reference system by providing a plurality of global reference marks that encompass up to the entire substrate wafer; and a plurality of alignment markings on a separate surface positioned facing the frontside of the substrate wafer in close proximity but on the opposite side of said substrate wafer alignment configuration for obtaining continuous six-axis control of a scanning probe tip with respect to said global coordinate reference system, the alignment markings comprising at least two second marking elements on the separate surface including grating elements having different periods, wherein said first marking element and second marking elements are illuminated at an oblique angle with light having a wavelength to which the substrate wafer is transparent or illuminated with infrared light in the silicon transparency band.