Atomic Force Microscope & White Light Interferometer in Situ Combination AFM-WLI Duet System，Providing Users with Convenient Cross-Scale Topography Characterization Solution

AFM-WLI Duet is a coaxial integrated system of the FreeSpirit ultra-thin head AFM-Piccolo and the Linnik type WLI-Marimba. The design of the AFM-Piccolo head is unique. Its effective thickness is less than 8 mm, and the thickness of the base part is less than 10 cm, making it highly convenient for integration with other system, including the White Light Interferometer (WLI). The Linnik type design of WLI-Marimba enables a sufficient working distance for the WLI, perfectly matching the desktop sized ultra-thin AFM-Piccolo head.

In certain applications where users require both large-scale rapid measurements and small-scale high-resolution measurements, the AFM-WLI Duet provides a convenient cross-scale measurement solution. It utilizes WLI for large-scale rapid measurements and AFM for small-area high-resolution measurements. The combination of both offers users a convenient in-situ cross-scale topography characterization solution.

The following shows a test case utilizing the combination of FreeSpirit AFM and WLI.

Figure 1 shows test results of a square grid using the AFM-WLI Duet. The Visual Image is directly observed with an optical microscope, revealing the square grid and probe cantilever. The central square region is selected for WLI imaging, as shown in the blue-green image with a 550 μm field of view. The red section image represents the height difference cross-section of the square grid. The protruding region of square grid is selected for AFM imaging, as shown in the yellow-brown image with a 50 μm scan range. The blue section image represents the grid height difference cross-section with a step height of approximately 105 nm. This data is consistent with measurements from the WLI.

Figure 1 Square Grid Image

Figure 2 shows images obtained by testing static random-access memory (SRAM) using the AFM-WLI Duet. The blue image on the left represents the WLI image of the SRAM with a field of view of 500 μm. The red part in the image is the AFM probe cantilever. The right side displays the topography image of the AFM test with a scan range of 20 μm. During testing, a large-scale WLI imaging of the SRAM is first obtained. Then select the interest regions and use the AFM probe to scan the small-scale area.

Figure 2 SRAM Image