Introducing the LEX/LEX3, new low energy high current implanters

As the design rule of semiconductor devices is shrinking, energy of ion implants is dramatically decreasing to make transistor junction depths shallower. The 0.5keV B
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and even 0.2keV B
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implants have been started to be used in volume production recently. However, productivity in such a low energy region is relatively low because of poor beam current due to difficulties of beam extraction and transport on ion implanter systems. The LEX is a next generation, ultra-low energy, high current ion implanter. This system has been developed to deliver production-worthy beam current even in the sub-keV region, employing newly designed beam optics and some new technologies which can reduce the so-called space charge effects. Significant increment of beam current has been achieved in the energy region below 10keV, needless to say, including the sub-keV region. For 300-mm wafer processing, the LEX3 also has been developed with the almost same beam-line and the same beam specification as the LEX. The system outlines, new technologies and performance of the LEX/LEX3 are described.