We make use of a flat (thickness ~ 0.5 mm) silicon (Si) sample carrier for bottom illumination AFM-IR in a commercial AFM-IR instrument. Through its micromachined bottom face this type of substrate enables attenuated total reflection measurements without the need for a large prism. Through rapid prototyping, a sample holder was designed to mount the carrier. The focal length of the system was adjusted by placing a removable lens in the beam path to allow changing back to conventional sample carriers. This new system is evaluated for measurements in air and in liquid. We are confident that this sample carriers will pave the way for a broader use of AFM-IR liquid studies, not only because of the lower cost of these sample carriers compared to prisms, but also because Si is a well understood material, with good resistance against solvents and a wealth of established procedures for surface functionalization described in literature.