Maskless micro-ion-beam reduction lithography

An ion projection lithography (IPL) technique called maskless micro-ion-bea m reduction lithography (MMRL) is being studied for future dynamic random a ccess memory and microprocessors manufacturing. In addition to minimum feat ure sizes of 50 nm or less required of next generation lithography, this MM RL system is proposed to completely eliminate the first stage of the conven tional IPL system that contains the complicated beam optics design in front of the stencil mask and the mask itself. Its main components consist of a multi-cusp, rf plasma generator, a multi-beamlet extraction system, and an accelerator column for beam reduction. The viability of this MMRL system hi nges upon the successful development of these components, most importantly the proposed all-electrostatic accelerator column. This article describes t he different components of the MMRL system and its ion optics. Computationa l results of beam demagnification and optics optimization are also presente d along with design progress of the prototype MMRL system. (C) 1999 America n Vacuum Society. [S0734-211X(99)12606-4].