Mass-producible monolithic silicon probes for scanning probe microscopes

In this paper, we describe the design, fabrication, and testing of monolithically micromachined silicon probes for scanning probe microscope (SPM) applications. An SPM probe consists of three parts: an atomically sharp tip, a supporting flexural beam, and a handle. Unique design and fabrication processes allow probes with uniform geometry to be developed efficiently. The process is robust, as no time-critical steps are involved. Tips are formed by anisotropic etching followed by oxidation sharpening. Monolithic process enhances reliability of the probe by eliminting post-fabrication assembly steps such as wafer bonding. We have demonstrated SPM probes with excellent mechanical characteristics, including high resonant frequency and zero intrinsic bending.