A method for production of cheap, reliable Pt-Ir tips

A new method of producing Pt-Ir tips for use in scanning tunneling microsco py is described. This reproducible method is simple, cheap, fast, and avoid s the use of hazardous chemicals common in many other methods. Scanning ele ctron microscopy, time of flight-secondary ion mass spectroscopy, and x-ray photoelectron spectroscopy have been applied to understand both the chemic al and morphological changes that occur as a result of the etching. The met hod has been demonstrated on both stock Pt-Ir wire and commercial tips and has been found to dramatically enhance image quality. It is also reusable o n the same tip extending the lifetime of a single tip indefinitely. (C) 200 0 American Institute of Physics. [S0034-6748(00)00904-7].