The Sensofar Scanning Confocal Microscope gives Phase Shift and White Light Interferometer options

The Sensofar scanning confocal microscope is a non­contact optical imaging profiler that has been developed using proprietary technology. The extremely high light efficiency of the illumination hardware and the high contrast algorithms are the main advantages of Sensofar's confocal arrangement, which make the system ideal for measuring steep slopes, rough and low reflective surfaces and samples containing dissimilar materials. The new dual technology illumination hardware uses a microdisplay format without any moving part inside the measuring head, making it suitable for OEM applications. With this system it is possible to choose between confocal imaging, confocal profiling, PSI (Phase Shift Interferometry) and VSI (White Light Vertical Scanning interferometry). The user chooses the right objective and selects the appropriate acquisition and data processing algorithms.

Phase Shift Interferometers measure the surface height of very smooth and continuous surfaces with sub-nanometer resolution. PSI can be used to measure large fields of view with the same height resolution. PSI algorithms enable Sensofar to profile shape features on the nanometer scale, as well as to assess texture parameters of super smooth surfaces on the sub-nanometer scale. White light vertical scanning interferometers measure the surface height of smooth to moderately rough surfaces. VSI algorithms enable Sensofar to use all the available magnifications to profile shape features with the same height resolution.

Combined with the interference techniques for very smooth surfaces, Sensofar provides a unique spectrum of applications.

The extremely simple and ergonomic software interface enables the user to obtain the requested measurement very rapidly, by simply choosing the right objective and focusing and selecting the appropriate acquisition technique.

Modularity

Considering the microscope objectives available today, Sensofarâ??s scanning confocal microscope offers a very broad range of magnifications (from 5x to 200x) and numerical apertures (from 0.15 NA to 0.95 NA). Super long working distance objectives (from 20X to 100X SLWD) can also be used to measure high aspect ratio features, large steps and steeply sloping samples. Sensofar has been designed as a modular system and many different configurations can be supplied, from the single sensor head for OEM applications to the most complete and sophisticated arrangement. The basic operative setup comprises the sensor head and the open-loop Z-scan device, which are mounted on a standard breadboard. This configuration provides the user with all the available imaging options (standard microscope, confocal and interferometry), as well as the highest resolution surface profiling techniques (confocal, PSI and VSI). Measuring thin films and thick layers is also possible. The highest quality EPI, ELWO, SLWO, 01 and TI Nikon objectives can be selected, with magnifications from 2,5X to 150X. To operate Sensofar using PSI and VSI algorithms, upgrading the hardware setup with a leveling tip-tilt stage and a vibration-isolation system is strongly recommended.

The system can also be upgraded with manual or motor X-Y stages, which are very useful for handling the sample and positioning the features to be measured within the field of view. Using the X-Y motor stage option, the user can operate Sensofar as a fully automated coordinate measurement system. Also, extended profile and extended topography measurements can easily be acquired using the stitching algorithms included in the software. A closed-loop PZT is also available as a high-accuracy z-scan option. By means of this device, Sensofar achieves sub-nanometer vertical resolution and calibration to traceable standards.