The semiconductor industry's progress toward new materials and fabrication methods is creating opportunities for effective, fast and nondestructive photonic metrology techniques. This applies along the entire chain of production, from wafer fabrication to packaging of the integrated chips. The metrology of integrated circuits, however, provides a functional snapshot of what challenges the industry confronts and what solutions photonics can provide. The gate length of transistors, for instance, is shrinking rapidly with each generation of integrated circuits. As this trend continues, it will become difficult to produce high yields of integrated circuits with consistent properties, such as clock speed - the rate at which a microprocessor executes directions...