ATOMIC LAYER-BY-LAYER SURFACE REMOVAL BY FORCE MICROSCOPY

Using an atomic force microscope (AFM) operating under ambient conditi ons, we have obtained the first atomic resolution AFM images of atomic -scale defects and have observed the scanning induced removal of atoms from lead pyrophosphate cleavage faces. Repeated scanning of the same surface area revealed cyclic changes in the Pb2P2O7 atomic structure consistent with a layer-by-layer removal of atoms. Subsequent large ar ea imaging of a region that had been subjected to repeated scanning re vealed a depression several nanometers deep, indicating that this tech nique may be applicable to patterning the surfaces of materials on an atomic scale.