Dimensional measurement of high aspect ratio micro structures with a resonating micro cantilever probe

Abstract

In non-destructive dimensional measurement of high aspect ratio micro structures (HARMS), optical methods cannot offer full three dimensional information due to the lack of observation light. Again, conventional mechanical measurement, such as a surface profiler or a coordinate measurement machine, cannot be applied because their stylus is too large. Furthermore, the AFM, though popular among the semiconductor industry, is also limited in terms of dimensional measurement, because its system is usually designed for planar samples. Thus, we have developed a new sensor-integrated micro resonating cantilever probe and a new dimensional measurement machine, which allows the probe's vertical access to microstructures in a sample. The new probe is made of tungsten carbide super hard alloy and possesses design flexibility according to its intended application. Validity of the system is confirmed through the measurement experiment of EDM drilled and chemically etched micro holes.