Development of a 3D measuring system for semiconductor patterned wafers

A fast, automated measuring system has been developed which provides 3D information about semiconductor wafer patterns nondestructively from scanning electron microscope images. The 3D measurement is conducted in two different ways for different patterns: one is pattern height measurement using only one image for trapezoidal patterns, while the other is height profile measurement for smoothly curved surfaces. The system proved capable of measuring 3D shape sufficiently fast (within 5 s) and with sufficiently good accuracy to control the semiconductor wafer process line. >