Development of an Extended Arc Plasma Source for Low-Pressure Surface Treatment

This study investigated the process of silicon etching by using a high durability plasmatron with the aim of increasing the size of the plasma jet for the treatment of wider wafer surfaces Different types of plasmatron nozzles and plasma reflectors were tested. By rising a two-plasmatron configuration, we succeeded in increasing the size of the etched spot by five to ten times the size achieved using a single plasmatron. The etch rates of silicon with CF4 and O-2 were 8 - 23 mu m/min. By using a magnetic field the plasma flow can be intensified and declined. This allows using magnetically- controlled surface scanning for etching processes.