Sub-5-nm-spatial resolution in scanning spreading resistance microscopy using full-diamond tips

Scanning spreading resistance microscopy is a two-dimensional carrier profiling technique now widely used for the characterization of silicon (Si) devices as well as other semiconductor materials. Whereas the state-of-the-art spatial resolution for this technique using commercial-diamond-coated silicon probes is limited to 10–20 nm, enhanced resolution is demonstrated through the use of full-diamond tips integrated in Si cantilevers. Sub-5-nm-spatial resolution is obtained on fully depleted silicon on isolator devices, putting the technique closer to the characterization requirements of the forthcoming semiconductor dimensions. Resistance and scanning electron microscope measurements clearly show that this enhanced resolution results from a smaller effective radius for full diamond tips as compared to the diamond-coated Si probes.