Ion source having replaceable and sputterable solid source material

Abstract

An ion source ( ) for an ion implanter is provided, comprising: (i) an ionization chamber ( ) defined at least partially by chamber walls ( ), and having an inlet ( ) into which a sputtering gas may be injected and an aperture ( ) through which an ion beam (B) may be extracted; (ii) an ionizing electron source ( ) for ionizing the sputtering gas to form a sputtering plasma; and (iii) a sputterable repeller ( ). The sputterable repeller both (a) repels electrons emitted by the electron source, and (b) provides a source of sputtered material that can be ionized by the electron source. The sputterable repeller ( ) comprises a slug ( ) of sputterable material, and further comprises mounting structure ( ) for removably mounting the slug within the ionization chamber ( ), so that the slug is made removably detachable from the mounting structure. The sputterable material may be any of the following elements, or compounds including any of these elements: aluminum (Al), boron (B), beryllium (Be), carbon (C), cesium (Cs), germanium, (Ge), molybdenum, (Mo), antimony (Sb), or silicon (Si). The repeller ( ) is negatively biased with respect to the ionization chamber walls ( ), and may be continuously variably biased to provide for a wide dynamic range of resulting ion beam currents.