Abstract: A system for scanning and measuring a surface charge of a sample immersed in a conductive medium, such as an aqueous electrolytic solution or a gel, or positioned on a conducting plate. The system has a semiconductor with a probing surface clad in a charge-sensitive layer. The probing surface moves over the sample during scanning while a bias voltage V.sub.BIAS is applied to create a depletion layer in the semiconductor and to induce the system to alter a measurable electrical property. The electrical property is monitored with the aid of a measuring device and the measurement is correlated to the sample's surface charge. In a preferred embodiment the semiconductor is a part of a cantilever structure of the type having a probing tip and the probing surface is located on the apex of the probing tip thereby enabling examination of the topology and surface charge of the sample concurrently.

Abstract: A deflection sensor for a microcantilever includes two sets of interdigitated fingers, one (reference) set being attached to the substrate from which the microcantilever extends and the other (movable) set being attached to the tip of the microcantilever. Together the interdigitated fingers form an optical phase grating. The deflection of the microcantilever is measured by directing a light beam against the optical phase grating and detecting the intensity of the reflected light in the first (or other) component of the resulting diffraction pattern. As the microcantilever deflects, the reference and movable fingers move relative to one another creating large variations in the intensity of the zeroth and first order components of the diffraction pattern. To eliminate "1/f" noise the deflection of the microcantilever can be measured using an AC signal.

Abstract: A thick column is formed by masking and etching a substrate, and the column is thinned to a very small diameter (e.g., .ltoreq.5 nm) by oxidizing the column and removing the oxide layer. A metal layer is deposited on the surface of the substrate, and the column and substrate are etched to form a pit. The backside of the substrate is etched to form an aperture surrounded by the metal layer. Alternatively, the metal layer is removed and a dopant layer is implanted into the substrate, followed by the etching of the backside, leaving an aperture surrounded by the dopant layer. In a second alternative, the oxidized column is broken from the substrate, and the backside is etched, leaving an aperture surrounded by an oxide layer. These processes can be used to fabricate apertures of very small and reproducible dimensions for such instruments as near field scanning optical microscopes and scanning ion conductance microscopes.

Abstract: A scanning probe microscope is used to pattern a layer of resist, and the pattern is transferred to a substrate. First, an underlayer formed of, for example, polyimide and a top layer formed of, for example, amorphous silicon are deposited on the substrate. A pattern is formed on the top layer using the tip of the cantilever in a scanning probe microscope. The pattern may consist of an oxide formed by an electric field at the cantilever tip. The top layer is then etched using the pattern as a mask and using an etchant that is selective against the underlayer. The underlayer is then etched using an etchant that is selective against the top layer and substrate. The substrate is etched with an etchant that removes the top layer but is selective against the underlayer. Finally, the underlayer is removed.