Carl Zeiss MicroImaging: New TIC Technique
November 6, 2003
Carl Zeiss MicroImaging has introduced a new total interference contrast (TIC) measuring technique for precise, low-cost step height and layer thickness measurement in materials microscopy. Contrary to traditional polarization interferometers, work in the new technique is carried out in circularly polarized light. The interference fringe can be aligned using the TIC slider without the time consuming sample orientation normally associated with polarization interferometers. The differences in the height of specimen structures are then determined by measuring the phase shift in the interference pattern. This technique effectively allows the measurement of step heights on the order of 20 nm to 5 microns, with a high degree of accuracy and repeatability.