Patent ID: 6326630
Filing Date: 2001-12-04
Classification: H01J

Abstract:
An ion implanter comprisingan ion source for generating an ion beam,a mass separator for separating and emitting only a necessary ion beam component from said ion beam,a post acceleration tube for accelerating said ion beam emitted so as to have energy necessary for an ion implanting,a quadrupole lens section for shaping said accelerated ion beam,an ion deflection section for isolating and removing beam components being neutral electrically from said shaped ion beam,an ion implanting chamber for implanting said ion beam to material,a vacuum expansion chamber provided between said post acceleration tube and said ion implanting chamber so that the vacuum degree of the ion implanting chamber is provided to be lower than that of the post acceleration tube so as to permit generation of a plasma in the ion implanting chamber, anda first beam limiter provided at an entry side of said vacuum expansion chamber and having a lower conductance than that of said post acceleration tube, and a second beam limiter provided at an exit of said vacuum expansion chamber and having a lower conductance than that of said vacuum expansion chamber, thereby creating a pressure gradient in the vacuum expansion chamber.