Atomic force microscope Si tip with Ge clusters with the capability of remoulding by heating

Commercially available Si cantilever tips for atomic force microscopy (AFM) are successfully modified to sharpen their tip apexes by depositing Ge on them in ultrahigh vacuum and subsequently heating. Even a slightly crashed Si tip is remoulded by this method of growing faceted Ge clusters on an expanded (001) facet at the apex. The AFM images are stably obtained over a few hours using the modified tips. These tips can be repeatedly remoulded by heating after breakage on scanning. This method is applicable to other materials, which are heteroepitaxially grown on Si in Stranski–Krastanov growth mode, to fabricate functionalized tips as per requirement.