Measurement of thermal deformation of IC packages using the AFM scanning moire technique

The scanning moire method was suggested in 1980s. A scanning moire method using optical method was proposed in 1993. The scanning lines in the SEM monitor or CCD video camera were utilized as the reference grating to form a scanning moire pattern. The available results are limited to the deformation measurement by using a grating with a frequency less than 250 lines/mm. Thus it is impossible to apply this method to measure deformation in nanometer scale. With the development of micro-mechanics and the appearance of nanometer mechanics, new techniques for deformation measurement form micrometer to nanometer scales are in urgent need.