Development of array-type atmospheric-pressure RF plasma generator with electric on–off control for high-throughput numerically controlled processes

Abstract

An array-type atmospheric-pressure radio-frequency (RF) plasma generator is proposed for high-precision and high-throughput numerically controlled (NC) processes. We propose the use of a metal-oxide-semiconductor field-effect transistor (MOSFET) circuit for direct RF switching to achieve plasma on–off control. We confirmed that this type of circuit works correctly using a MOSFET with a small parasitic capacitance between its source and gate. We examined the design method for the distance between adjacent electrodes, which corresponds to the parasitic capacitance between adjacent electrodes and is very important in the individual on–off control of each electrode. We developed a prototype array-type plasma generator apparatus with 19 electrodes and the same number of MOSFET circuits; we then confirmed that each electrode could control its plasma on–off state individually. We also demonstrated that the thickness uniformity of the surface Si layer of a silicon-on-insulator wafer could be processed to less than 1 nm peak to valley by the NC sacrificial oxidation method using the apparatus.

High-throughput deterministic plasma etching using array-type plasma generator system

“…We have designed and fabricated an array-type electrode plasma generator, demonstrated that each electrode's plasma can be individually turned on and off regardless of the adjacent electrodes' on-off status, and demonstrated highly efficient NC sacrificial oxidation processing. 23,24 Thus, herein, we attempt to apply an array-type electrode plasma generator to PCVM, a plasma etching technique using a high-pressure plasma. 9 In PCVM, the gas composition in the plasma changes moment by moment due to the rapid consumption of reaction gases and the creation of gas-phase reaction products because of the high-speed plasma etching process.…”