Schematic view of a wafer warp. The warp is revealing the curvature of a wafer. It is calculated from a measure of the maximum deviation from the reference plane (MAX) and the minimum deviation from the reference plane (MIN). The warp value is equal to the difference between MAX and MIN.
Capelle et al. Nanoscale Research Letters 2012 7:523 doi:10.1186/1556-276X-7-523