Scanning Thermal Microscopy Module (SThM)
This module (comprising controller, software and probes) enables most AFMs to be able to do temperature mapping of their sample with 0.1ºC resolution.The Scanning Thermal Microscopy (SThM) module from Anasys Instruments enables a number of commercially available Atomic Force Microscopes to generate nanoscale thermal images while simultaneously obtaining contact mode images of the topography. It includes hardware, software and probes and optionally a cantilever holder designed for your AFM. The SThM capability is a subset of the full suite of thermal analysis methods available, and can be easily upgraded to the full NanoTA2 system if your applications
require that capability.
The SThM mode works by replacing the standard contact mode AFM probe with a specialized probe that incorporates a resistor near the apex of the probe tip.This resistor is incorporated into a Wheatstone bridge circuit which allows the system to monitor the resistance. The resistance correlates with the temperature at the end of the probe,which can be used to both monitor the temperature of a sample as well as map out the thermal conductivity of the sample in a qualitative manner. Sample temperatures are typically measured on active device structures, such as magnetic recording heads,laser diodes or electrical circuits. Conversely, thermal conductivity is more typically measured on composite samples. In this measurement,a higher voltage is applied to the probe increasing it further above room temperature.The thermal conductivity of the sample will affect the temperature of the probe by draining more or less heat away from the tip. Shown to the left is an image from a fiberglass sample showing the epoxy between three
glass fibers.The sample has been sectioned and polished so the surface is flat. Planarization improves the performance of the SThM mode, whereas, significant topography can induce artifacts in the SThM image. The scan size is 3 ìm with the topography on the left and thermal image on the right.