Large-area ion source combining microwaves with inductively coupled plasma

Abstract

The semiconductor industry is growing rapidly and requires high technologies for nano-structure devices. Ion sources for manufacturing the next-generation semiconductor devices have been studied from the viewpoint of applications to material processing, such as ion beam assisted deposition, ion beam etching, and ion implantation. Recently, large-area ion sources which extract broad ion beams with multiapertures have come to be required not only for processing the size-growing wafers but also for industrial applications to nonsemiconductor materials. However, the uniformity of plasma density over the multiaperture electrodes has not met the requirements yet. We suggest a new method to improve the uniformity by superposing microwaves to an inductively coupled plasma source. Distributions of ion species in the plasma are measured with a quadrupole mass spectrometer which can be moved in vacuum perpendicularly to the beam extraction. The distributions of both plasma density and ion species in the source plasma as well as their properties over a large area are being studied and discussed.