A small-scale and low-power 13.56 MHz capacitively coupled plasma is generated in a capillary, whose cross section is 65–500×500–5000 µm, on a quartz chip of 20×20 mm at atmospheric pressure. The capillary is sandwiched between parallel-plate electrodes which are externally located on a chip. A π-type matching network is miniaturized and appropriately designed to satisfy the resonance condition with the excitation frequency, so that helium plasma ignites at an incident power of1–3 W. The atomic excitation temperature measured from the intensity distribution of He I lines is about 1900 K at atmospheric pressure. This result suggests that a low-electronic-temperature plasma is obtained.

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