A provisional patent has been filed on the device. What this means to the semiconductor industry is that particles with diameters less than 0.1 micrometer soon may be routinely discernible. The Semiconductor Industry Association roadmap declared that, in the future, such ability would be a breakthrough advance toward the manufacture of tinier integrated circuits. In addition to its usefulness in process inspection of silicon wafers, bidirectional ellipsometry is expected to become a powerful technique for identifying and characterizing defects in optical components, disk storage materials and film coatings. NIST scientists have made measurements of the index of refraction of fused silica and calcium fluoride at wavelengths near 193 nanometers.
Engineers require such precise data to design accurately components for the photolithographic tools.
To make the index of refraction measurement accurate to 10 parts in a million, the researchers upgraded a precision refractometer, which is capable of temperature control of 0.1 degrees Celsius. For the longer term and for shorter wavelengths, they are developing interferometric methods capable of higher accuracy.