SIMS IMAGING OF INSULATOR SURFACES

Imaging of secondary ions emitted from bare insulator surfaces has bee n carried out on a Cameca IMS 3F secondary ion mass spectrometer witho ut the use of electron beam, conductive grid or coating methods. This was accomplished by analysing secondary ions with kinetic energies ran ging from 200 to 350 eV emitted from charge-stabilized samples. Charge stabilization was attained by placing the sample under various forms of specimen isolation. images from both 0(-) and Cs+ primary ion-bomba rded surfaces were collected, with several examples shown; 0(-) provid ed the better spatial resolution due to improved sample potential stab ility. Mechanisms associated with charge stabilization and image disto rtion are elaborated upon with the aid of computer simulations.