Characteristics of parallel internal-type inductively coupled plasmas for large area flat panel display processing

The development of a large-area high-density plasma source is desired for various plasma processes from microelectronics fabrication to flat panel display (FPD) device fabrication. In this study, using a parallel internal-type (double comb-type) inductively coupled plasma source having the size of 1020 mm × 830 mm, high density plasmas on the order of 2.2 × 10¹¹ cm^-3 could be obtained with Ar at 5000 W inductive power. Plasma uniformity on the substrate in the size of 920 mm × 730 mm decreased with the increase in inductive power and was about 8% when the inductive power was 5000 W. When SF₆ was used to etch SiO₂ using the source, the SiO₂ etch rate higher than 2000 Å/min with an etch uniformity of about 6% could be obtained at 5000 W inductive power, -350V bias voltage, and 15 mTorr operating pressure.