Increasing the value of atomic force microscopy process metrology using a high-accuracy scanner, tip characterization, and morphological image analysis

Atomic force microscopes are being used increasingly for process metrology. As a case study, the measurement by atomic force microscope of a soda lime glass optical disk patterned using optical lithography and reactive plasma etching is examined. The atomic force microscope used for this measurement has a highly accurate scanner system. The X, Y, and Z axes are calibrated using laser interferometry. To determine the shape of the tip used a commercially available tip calibration artifact was imaged both before and after the measurement. The image was corrected for the tip shape using mathematical morphology. The value of the atomic force microscope measurement is defined to be the impacts of the metrology on the product or process. It is shown that the value of atomic force microscopy process metrology on an optical disk is increased by using an accurate scanner, tip characterization, and morphological image analysis; however, the cost per measurement is increased as well. In general, the characteristics of the metrology required depends on the specific manufacturing process being supported.