Scatterometry applied to microelectronics processing

This past decade has seen the development of a non-imaging optical dimensional metrology technique known as scatterometry. Scatterometry is a nondestructive optical technique that records and analyzes changes in the intensity of light reflected from a periodic scattering surface. By measuring and analyzing the light diffracted from a patterned periodic sample, the dimensions of the sample itself can be measured. Scatterometry exploits the sensitivity of diffraction from a sample to changes in the line-shape of the sample. The use of an elementary sample illumination system, combined with a rigorous scattered signal analysis procedure presents a significant advantage over conventional metrology techniques. These are discussed in detail in this paper.