Novel high resolution scanning thermal probe

Abstract

Scanning thermal microscopy is a scanning proximal probe technique, which can be used for mapping spatial variation of thermal properties of a surface such as temperature, thermal conductivity, and thermal diffusivity. The sensor presented here is a resistance based probe consisting of a nanometer-sized filament formed at the end of a piezoresistive atomic force microscope type cantilever. The freestanding filament is deposited by focused electron beam deposition using methylcyclopentadienyl trimethyl platinum as a precursor gas. The filament height is in the range of 2–5 μm, with typical “wire” diameters between 30 and 100 nm. Typical deposition times are between 2 and 5 min, and might be further shortened by optimizing the precursor gas flux. Because of its small size, the new probe has a high spatial resolution (<20 nm tip end radius) and, due to the low thermal mass, a high thermal sensitivity and fast response time. In this article, experiments designed to characterize the mechanical stability and electrical and thermal properties of the nanometer-sized probe are presented.