Reduction of the electrostatic coupling in a large-area internal inductively coupled plasma source using a multicusp magnetic field

Abstract

A large area (1020mm×830mm) inductively coupled plasma (ICP) source has been developed using an internal-type linear antenna with permanent magnets forming a multicusp magnetic field. The large rf antenna voltages, which cause the electrostatic coupling between the antenna and the plasma in a large area internal-type linear-antenna ICP source, were decreased significantly by applying the magnetic field near and parallel to the antenna. Through the application of the magnetic field, an approximately 20% higher plasma density, with a value of close to 1.0×1011cm−3 at a rf power of 2000W, and about three times higher photoresist etch rates were observed, while maintaining the plasma nonuniformity at less than 9%.

Inductively Coupled Plasma Source Using Internal Multiple U-Type Antenna for Ultra Large-Area Plasma Processing

“…As shown in the figure, the RF RMS voltage increases with the increase in RF power for both antennas and the grounded antenna shows higher RF antenna voltage compared to the grounded antenna. High RF RMS voltage on the antenna can increase the dc voltage induced on the quartz tubing covering the antenna and can increase the sputtering of the dielectric material of the tubing which increases the particles and contamination to the substrate in addition to the unstable plasma characteristics 11–14. The effect of the reduced rms rf coil voltage on the decrease of quartz tube sputtering is confirmed by measuring the dc potential shift on the insulator covering the antenna.…”

Discharge profiles of internal-antenna-driven inductively-coupled plasmas

“…Currently, the ICP sources applied to semiconductor and FPD processing are required to attain dense uniform plasma generation over large area and lowering of plasma damage to materials surface under processing. However the scale-up of the conventional ICPs with spiral antenna coils leads to problems including large antenna impedance, which causes huge RF voltages (1-10 kV order) at the powered end of the antenna, thick dielectric window between the plasma and the antenna and the standing wave effects [4][5][6][7][8][9].…”

Scalable internal linear double comb-type inductively coupled plasma source for large area flat panel display processing

“…The scale up of an ICP source to a large, uniform, high density plasma source is not an easy task [5][6][7][8]. It requires a carful design of antennas allowing the generation of a largearea and uniform electromagnetic field in the source.…”