Scanning tunneling microscope study of small metal particles--the understanding of the electronic properties of small pieces of metal is a subject of growing importance as the microelectronics industry pushes toward smaller circuitry. As the size of a block of metal diminishes, new effects, not visible in larger samples, arise and eventually dominate simple ohmic metallic behavior. For sizes less than roughly 1000A, at least three small size effects must be considered: quantum size effects, discrete charging effects, and weak localization. To study these effects in small (10A-1000A) normal metal and superconducting particles. I am constructing a cryogenic scanning tunneling microscope (STM) capable of electronic energy level spectroscopy on individual particles. With the STM, I will investigate a size regime as yet inaccessible to lithographic techniques while avoiding the ambiguities of ensemble averaging by probing single particles.
