Microdeflectometry: SEM-like quantitative 3D images with nanometer height sensitivity

"Microdeflectometry" is a novel technique to measure the microtopography of specular surfaces [1]. The primary data is the local slope of the surface under test. Measuring the slope instead of the height implies high information efficiency and extreme sensitivity to local shape irregularities. The accessible slope angle is up to +/- 65°. The lateral resolution can be better than one micron whereas the resulting height resolution is in the range of one nanometer. We demonstrate that, in addition, microdeflectometry can be supplemented by the expansion of the depth of focus, with the potential to provide quantitative 3D imaging with SEM-like features. [1] Häusler at al.: "Microdeflectometry - a novel tool to acquire 3D microtopology with nanometer height resolution", Optics Letters (accepted for publication)