Recent results employing scanning tunneling microscope‐based techniques for the generation of nanometer‐scale patterns on passivated semiconductor surfaces are presented. Preparation and characterization of hydrogen‐passivated silicon and sulfur‐passivated gallium arsenide surfaces are described and the determination of the chemical and morphological properties of the patterned regions by scanning electron microscopy and time‐of‐flight secondary ion mass spectrometry are discussed. Our recent demonstration that ultrashallow, oxide features written by scanning tunneling microscope (STM) can serve as an effective mask for selective‐area GaAs heteroepitaxy on silicon is used to illustrate key requirements necessary for the realization of a unique, STM‐based nanotechnology.