Ion current density and its uniformity at the electron cyclotron resonance position in electron cyclotron resonance plasma

Abstract

Extremely high and uniform ion current density is achieved at the electron cyclotron resonance (ECR) position in a microwave cavity resonator with a 260 mm diam. Microwave power is most efficiently absorbed at the ECR position in the ECR plasma. The uniformity of the ion current density at the ECR position is 15±0.75 mA/cm2 in a 200 mm diam area. This high and uniform ion current density is accomplished with a large quartz window size with a 170 mm diam for microwave introduction and a flat profile of the 875 G equimagnetic field position. The ECR plasma etching system equipped with this microwave cavity resonator that is 260 mm in diameter has a high potential for uniform and high rate pattern fabrication in a ULSI circuit on a more than 6 in. diam substrate.