To achieve a reasonable SNR the incoming beam is focused directly under a gold coated cantilever tip. Ramer et. al. demonstrated an improvement of SNR in water over measurements in air and used AFM-IR to analyze fibril secondary structure in water and heavy water. These studies all have in common, that they rely on IR transparent prisms as sample carriers in bottom illumination AFM-IR geometry similar to the configuration used in the original demonstration of AFM-IR by Dazzi et. al. as well as the first commercial AFM-IR systems. In this geometry, the laser beam passes through a high refractive index infrared transparent prism and interacts with the sample via an evanescent wave, localized at the interface, generated through an attenuated total internal reflection. The illumination through the prism eliminates the loss of attenuation of the pump beam in water moving towards the sample and the attenuated total reflection concentrates the sample intensity at the surface in the sample, reducing the signal due to absorption in water. However, bottom illumination AFM-IR (both in liquid and in air) comes with several drawbacks stemming from the size and the materials of the required prisms. Only a few materials combine the required high refractive index and infrared transparency. Typically, ZnSe (zinc selenide) and ZnS (zinc sul-fide) are used, but Ge (Germanium) has also been reported. ZnSe and ZnS are not suitable for acidic samples or liquids. Furthermore, because of their shape, size, and "exotic" chemistry, these prisms are incompatible with many established surface functionalization protocols and tools. Finally, these prisms are significantly more expensive (10 -100 times) then sample carriers for the more common top illumination AFM-IR illumination scheme.