The antenna of the plasma system for processing the semiconductor wafer or LCD is formed into rhomboid. Therefore, it can be processed while enhancing the plasma density at the end part of the processed product of square or the bar type. The plasma system is comprised as follows. A power source is for supplying the RF power. The processed product is positioned in a chamber. The plasma is generated in the chamber. The rhombic antenna is for converting the RF power into the electromagnetic field. The adapter controls the impedance of the RF power. The air exhausting unit is for exhausting the reaction gas within the chamber. The antenna is formed into the coil type to deliver the energy to the chamber by the inductively coupled method. The antenna comprises the power inlet(21) for electricity and the power outlet.
