Micro-scale features (XY/Z)
Nano-scale features (Z)
High local slopes
Confocal profiling is ideal for smooth to very rough surfaces. It provides the highest lateral resolution, so that spatial sampling can be reduced to 0.01 µm, making it ideal for critical dimension measurements. High NA (0.95) and magnification (150X) objectives are available to measure smooth surfaces with steep local slopes over 70º (for rough surfaces up to 86º). Propietary algorithms provide unique vertical repeatability on the nanometer scale.
The confocal scanning technique implemented in Sensofar’s systems utilizes a patented microdisplay scanning technology. The microdisplay is based on ferroelectric liquid crystal on silicon (FLCoS) technology, creating a rapidly switching device with no moving parts and making data acquisition fast, reliable and accurate. Due to this and the associated algorithms, Sensofar’s confocal approach yields class-leading vertical resolution, better than other confocal approaches and even better than laser scanning confocal systems.
White-light vertical scanning interferometry (VSI) is a widely used and powerful technique for measuring surface characteristics such as topography or transparent film structure. It is best suited for measuring smooth to moderately rough sourfaces, and provides nanometer vertical resolution regardless of the objective’s NA or magnification.
Focus Variation is an optical technology that has been developed for measuring the shape of large rough surfaces. Sensofar’s implementation of this approach has been specifically designed to complement confocal measurements at low magnification. Highlights of the technology include high slope surfaces (up to 86°), highest measurement speeds (mm/s) and large vertical range. This combination of features is largely suited to tooling applications.