Low-temperature atomic force microscope using piezoresistive cantilevers

This article describes the design of an easy-to-operate low-temperature ato mic force microscope (AFM) that incorporates piezoresistive cantilevers. Th e instrument is easier to build and to operate at cryogenic temperatures th an AFMs based on laser deflection schemes or interferometers because no mec hanical adjustments of the instrument are necessary after a change of tempe rature. The effects of thermal expansion on the AFM's tip-to-sample distanc e are minimized by the use of a double tube scanner assembly. The design in cludes a simple mechanism that locks the sample holder in place as the temp erature is lowered. This AFM is compact and rigid, enabling it to be used i n a conventional cryogenic liquid-storage Dewar. All of the materials used in the construction of the AFM are ultra-high-vacuum compatible. [S0034-674 8(99)01508-7].