In this paper, we focus on the thermally treated atomic force microscope tips used in the investigation of the resistive switching phenomenon. Since the resistive switching phenomenon is often connected with the red-ox process, it is crucial to investigate the influence of oxidizing and reducing conditions at elevated temperatures on typical AFM tips. To fully characterize the influence of different conditions on the tip properties we used several techniques such as: X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and local-conductivity atomic force microscopy. The chemical composition as well as the topography and morphology of the most popular Pt/Ir coated silicon tips were investigated. The influence of thermal treatment on the tip apex was also imaged and the changes in the electrical behavior of the tip coating were observed. Applied temperatures ranges were: 500-700 degrees C for oxidizing conditions (air) and 300-700 degrees C for reducing conditions (vacuum 10(-6) Torr), the annealing time was set to 0.5 h. Results yielded the formation of Pt2Si and SiO2 on the tip surface. The Pt tends to agglomerate into particles over time, depending on the temperature and conditions. The tip apex radius increases while the electrical conductivity decreases with the temperature. In conclusion, even the lowest applied temperature leads to changes in the tip properties, while these changes are much more pronounced under oxidizing conditions. (C) 2011 Elsevier B. V. All rights reserved.