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Product Briefing Outline: Veeco Instruments recently launched the Dektak 150 Surface Profiler, which is designed to monitor thin films of advanced PVs as well as critical surface roughness, key for optimal absorption of photons. The standard Dektak 150 utilizes a newly designed 4 x 4-inch X-Y stage with manual theta. It can be configured with a 4-inch Y auto stage that enables 3D imaging, or equipped with a 6-inch X-Y auto stage that, in addition to 3D mapping, provides automation and programmability of over 200 sample sites. With the scan-stitching package, the system can perform even longer scans for stress measurements on larger wafers. Other stage features include wafer alignment pins for ease of use, three-point suspension for stress, lateral calibration for 99.9% accuracy, and a larger scan block for improved baseline stability, according to the company.

Problem: There is a growing need to be able to monitor thin films of advanced PVs as well as critical surface roughness, which is a key for optimal absorption of photons, and improving overall efficiency. Improved precision, while offering a wide application use, is required to provide cost effective analysis.

Solution: With 6-angstrom step-height repeatability, the Dektak 150 profiler provides the flexibility to perform precise step-height measurements for thin films down to less than 100 angstroms, as well as thick-film measurements up to several hundred microns thick. The Low-Inertia Sensor 3 (LIS 3) head is claimed to deliver extremely accurate measurements with unprecedented sensitivity. The 512-micron vertical range is claimed to be the best standard Z performance in the industry, and a 1-millimeter option extends the vertical range of these systems even further. Improved horizontal and vertical resolution enables precise planarity scans for measuring radius of curvature, flatness, and waviness, as well as characterizing thin-film stress on wafers.

Applications: Thin films

Platform: The Dektak 150 incorporates a cast-aluminum frame and several vibration and noise reduction features to provide the lowest possible noise floor for measuring extremely thin films, according to the company. In addition, the Dektak 150 is able to measure thin film stress with longer scan lengths up to 55 millimeters and a larger vertical range up to 1 millimeter. The thin film stress measurement software automatically calculates compressive or tensile stress. Plus, the Dektak 150 offers 3D imaging capabilities to map a user-defined surface area to perform in-depth analysis of surface defects and area roughness with Veeco’s ‘Vision’ 3D analysis software.

Availability: Summer 2007 onwards.