Multi-dimensional search techniques in low energy ion beam optimization

As device geometries continue to shrink, so do implanter beam energies. High current, low energy beams are difficult to achieve because of space charge expansion effects. As a result, low energy beam production and control schemes usually involve the use of precision moving parts and many control parameters. This paper contains a brief review of traditional ion beam tuning techniques. It describes a number of techniques which have been used or developed to search a multi-dimensional electronic control space in the magnet of the Eaton ULE2 ion implanter system. The paper presents graphical results for the various techniques and discusses their advantages, disadvantages and possibilities