Pyramidal nanowire tip for atomic force microscopy and thermal imaging

We present a novel 3D nanowire pyramid as scanning microscopy probe for thermal imaging and atomic force microscopy. This probe is fabricated by standard micromachining and conventional optical contact lithography. The probe features an AFM-type cantilever with a sharp pyramidal tip composed of four freestanding silicon nitride nanowires with a diameter of 60 nm. The nanowires, which are made of silicon nitride coated by metal, form an electrical cross junction at the apex of the tip, addressable through the electrodes integrated on the cantilever. The cross junction on the tip apex can be utilized to produce heat and detect local temperature changes. Electrical and thermal properties of the probe were experimentally determined. The temperature changes in the nanowires due to Joule heating can be sensed by measuring the resistance of the nanowires. We employed the scanning probe in an atomic force microscope.