Wafer-scale fabrication of scanning thermal probes with integrated metal nanowire resistive elements for sensing and heating

Scanning Thermal Microscopy (SThM) and micro-thermal analysis allow the study of thermal phenomena at micro- and nanoscale. We present a novel scanning resistive probe aimed for thermal imaging and localized thermal analysis. The probe features an AFM cantilever with a sharp pyramidal tip. Metal nanowires are integrated at the inner edges of the pyramidal tip forming an electrical cross-junction at the apex. The nanometer-sized cross-junction, addressable through microelectrodes, can be utilized both as a local temperature sensor and a heater. We have fabricated a first prototype of the probe with a 150 μm long, 36 μm wide and 0.5 μm thick silicon nitride cantilever. Platinum nanowires, 300 nm wide and 100 nm thick, are successfully integrated using a wafer-scale fabrication process based on corner lithography. We have experimentally characterized electrical and thermal properties of the probe demonstrating its proper functioning.