Abstract

To keep pace with device technology as it pushes towards 100-nm line widths and gigahertz operating speeds, new measurement tools are needed for studying mesoscopic device physics and for testing and designing the next generation of ultra-dense integrated circuits. A promising new direction is the use of scanning probe microscopes for such measurements, by utilizing probe tip nonlinearities for heterodyning very high-speed signals.[1-6] We have developed such an ultrafast system, based on the scanning force microscope (SFM), that should theoretically be able to map a voltage profile with subpicosecond temporal resolution and submicron spatial resolution. Furthermore, it is non-invasive, rugged, and does not require vacuum. By using the square-law force interaction between the SFM and sample for mixing and sampling, we have measured voltage transients as fast as 5 picoseconds. We have also used this system to probe VLSI integrated circuits.

© 1995 Optical Society of America