Global model analysis of Ar inductively coupled plasma driven by a 150 kHz-band high-power pulse burst

Abstract

The behavior of argon inductively coupled plasma (ICP) driven by a 150 kHz-band high-voltage pulse burst is investigated using the mutual induction circuit model and a spatially averaged global model. A high-voltage of 4 kV was applied to the 50-turns solenoid coil to generate a magnetic field in the 52 mm inner diameter glass tube. The coil current of 47 A flowed into the solenoid coil with 83 Ω of equivalent load impedance before the plasma ignition. The coil voltage and current decreased to 2.0 kV and 30 A with plasma ignition. The measured waveforms of the coil voltage and current were used to obtain the electrical characteristics based on the equivalent circuit with the mutual induction circuit model. The magnetic coupling factor was obtained to be in range from 0.6 to 0.7 at various gas pressers and input power. The characterization of the ICP was analyzed using the global model with 200 μs width burst pulse. The electron temperature and plasma density were obtained as 2–3 eV and 1019 m−3, respectively, at an input power of several kilo-watts. These values were almost consistent with those measured using a double probe. The densities of the exited argon atom were estimated to be 1017 m−3.

Comparison of plasma characteristics of high-power pulsed sputtering glow discharge and hollow-cathode discharge

“…The ratio of transition from excitation (Ar I) to ionized states (Ar II) by electron collision and the electron collisional excitation (Ar I) increases with increasing input power. 20) Therefore, in the HPPS, the intensity of the excited state of Ar decreases and the intensity of singly ionized Ar increases in comparison to HCD.…”

“…The inductively coupled impulse sputtering method utilizes a high-density (10 19 m −3 or more) ion source that does not require an externally applied magnetic field. [19][20][21] The hollow cathode discharge (HCD) are also effective for high-density plasma production. 22,23) The hollow cathode traps electrons in a hollow cylinder or between two parallel plates.…”

Time-resolved observation of 150 kHz high-power pulse burst high-frequency discharge using a high-speed video camera and an intensified charge coupled device camera

“…24,25) This method has advantages such as eliminating the impedance matching device, high plasma density of 10 19 to 10 20 m −3 generated by high-power input to the plasmas, and easy process optimization by flexible adjustment of the burst width and duty cycle. Although sputtering and etching applications using combined burst and pulse power sources have been reported, [26][27][28] fundamental reports on plasma characteristics and discharge principles are lacking. In contrast to the steadystate illumination of plasma in a normal 13.56 MHz band ICP, burst-type RF discharges are transient phenomena and have a different discharge principle from that of normal ICP.…”

Silicon Wafer Etching Rate Characteristics with Burst Width Using 150 kHz Band High-Power Burst Inductively Coupled Plasma

“…A new ICP system using burst waves has been developed [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. In this system, the frequency is set to 100–200 kHz, which is not necessary for the impedance matching circuit required in conventional ICP systems, and the resonance between the ICP inductance and the parallel capacitance produces high-density plasma of the order of 10 19 m −3 [ 12 , 13 , 14 , 15 , 16 , 17 ]. Therefore, this ICP system has the advantage of a simple equipment configuration.…”