Force Measurement With High Sensitivity Application to Surface Inspection at the Angstrom Scale
Original Publication Date: 1987-Nov-01
Included in the Prior Art Database: 2005-Feb-02
A new technique measures forces, down to 5 x 10-16N on a sub-micron scale. A small tip, having a diameter D&100Ao, at the end of a spring is vibrated close to a solid. Linear and non linear AC contact forces between the tip and the solid are measured through the resulting tip displacement with a highly sensitive laser probe. Profiling and "contact" inspection can be done nondestructively on an Angstrom scale. In operation, a metallic spring tip is mounted on a small PZT transducer and vibrated close to the surface of the solid to be examined. A laser heterodyne probe accurately measures the AC displacement of the spring.