200 kV focused ion beam system

In recent years, there has been an increasing interest in finely focused ion beam system using a liquid metal ion source (LMIS) for semiconductor device fabrication. Maskless ion implantation using a liquid metal alloy ion source is prospective due to process simplification and its ability to control the dose and the doping depth. The LMIS is able to obtain doubly charged ions which are applicable to Si and GaAs devices. Doubly charged ions may be advantageous for effectively doubling the accelerating voltage in ion implantation. The authors have developed an FIB system employing a 200 kV accelerating voltage, which should be a promising system for maskless ion implantation. This new 200 kV FIB system capable of obtaining a spot diameter smaller than 100 nm, confirmed by resolution of secondary electron images