Generation of self-ignition plasma and extracted ion current in a burst RF inductively coupled plasma of carbon-containing gases

A self-ignition plasma (SIP) is generated around a target by applying a pulsed voltage of more than −1.2 kV in a burst rf (222 kHz) inductively coupled plasma (ICP). The plasma is generated from methane or ethane at pressures of 3–4.5 Pa. The SIP is generated at pulsed voltages of more negative than −1.2 kV about 3 μs after pulse application. Fundamental electrical properties are obtained for target voltages of 0.8–10 kV, and the ion current in presence and absence of the burst rf plasma is calculated. Generation of the SIP results in a dual plasma structure and the extracted ion current increases. The contribution of the SIP to the extracted ion current increases with the target voltage, and is responsible for 90% of the ion current at −10 kV.